+

WO1999026974A1 - Proteines et peptides stimulant la croissance in vitro et in vivo pour cellules epitheliales renales - Google Patents

Proteines et peptides stimulant la croissance in vitro et in vivo pour cellules epitheliales renales Download PDF

Info

Publication number
WO1999026974A1
WO1999026974A1 PCT/US1998/010574 US9810574W WO9926974A1 WO 1999026974 A1 WO1999026974 A1 WO 1999026974A1 US 9810574 W US9810574 W US 9810574W WO 9926974 A1 WO9926974 A1 WO 9926974A1
Authority
WO
WIPO (PCT)
Prior art keywords
peptide
wgf
protein
cells
mitogenic
Prior art date
Application number
PCT/US1998/010574
Other languages
English (en)
Inventor
Gary F. Toback
Margaret M. Walsh-Reitz
Original Assignee
Arch Development Corporation
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from US08/974,775 external-priority patent/US6096706A/en
Application filed by Arch Development Corporation filed Critical Arch Development Corporation
Priority to CA002310677A priority Critical patent/CA2310677C/fr
Priority to AU76935/98A priority patent/AU745894C/en
Priority to DE69821025T priority patent/DE69821025T2/de
Priority to EP98924865A priority patent/EP1034187B1/fr
Priority to JP2000522130A priority patent/JP3820102B2/ja
Priority to AT98924865T priority patent/ATE257486T1/de
Publication of WO1999026974A1 publication Critical patent/WO1999026974A1/fr

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07K—PEPTIDES
    • C07K14/00—Peptides having more than 20 amino acids; Gastrins; Somatostatins; Melanotropins; Derivatives thereof
    • C07K14/435—Peptides having more than 20 amino acids; Gastrins; Somatostatins; Melanotropins; Derivatives thereof from animals; from humans
    • C07K14/475—Growth factors; Growth regulators
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K38/00—Medicinal preparations containing peptides

Definitions

  • Novel growth peptides derived from protein factors having molecular weights of about 22 and 45 kDa stimulate mitogenic activity of epithelial, but not flbroblastic cells, in particular, kidney epithelial cells in culture. These growth promoting effects were also demonstrated in vivo.
  • Acute renal failure is a serious disease associated with high mortality for which no "real" treatment currently exists.
  • Acute renal failure is defined as the abrupt disruption of previously normal kidney function. It is caused by a wide variety of mechanisms including circulatory failure (shock), vascular blockade, glomerulonephritis, and obstruction to urine flow. In addition it can occur following surgery, trauma, sepsis, or with certain medications, particularly antibiotics and anticancer agents.
  • kidney disease contributes to major medical costs in the United States, so factors reducing time to recovery, are beneficial to society.
  • Dialysis is a technique in which impurities and toxins from the blood, that are normally cleared through the kidneys are artificially removed through an extra- corporeal circuit and filter (hemodialysis) or through the peritoneal membrane. By removing such impurities the life threatening metabolic imbalances resulting from kidney failure can be corrected and the patient stabilized.
  • kidney is one of the few human organs that has an ability to repair itself after injury Even in cases where the kidney has been irreversibly damaged, and there is extensive necrosis of kidney cells, strong evidence exists that some new cell growth occurs
  • growth factors are a therapeutic approach to stimulate or augment the regenerative process in the injured kidney and thereby reduce the seventy and shorten the course of acute renal failure
  • the use of growth factors as a treatment for acute renal failure was first proposed by Toback (1984) However, finding suitable growth factors proved difficult
  • the rationale for this strategy was subsequently expanded after several specific growth factor proteins were identified (Mordan and Toback, 1984, Toback 1992, Mendley and Toback, 1989, Toback 1992 a and b)
  • growth factors acting in vivo to stimulate proliferation and migration of noninjured tubular cells in the kidney, and possibly to facilitate recovery of sublethally-injured cells as well, would be beneficial
  • a specific growth factor could be used in combination with sufficient nutrients, calories, and dialytic therapy to increase survival of patients with renal problems
  • administration of growth factors could (1) increase positive outcomes in patients with cadaveric renal transplants, a situation in which acute renal failure is associated with increased rejection, (2) shorten the duration of acute renal failure which
  • Autocrinc growth factors are produced locally by the same cells on which they act. They appear to be produced in response to a stimulating event such as cell injury. Moreover, they are produced in extremely small quantities and may exist at detectable levels for only a short time. Consequently, they have been quite difficult to isolate and identify.
  • paracrine and endocrine both appear to have some role in stimulating kidney cell growth.
  • Paracrine factors act on adjacent cells (rather than on the cells that produced them) while endocrine factors are produced in one cell and transported (e.g., by the blood stream) to act on another, distant cell.
  • endocrine factors which are typically produced in larger quantities, and have a longer "half life" than some autocrine factors, have been discovered, and their cDNAs identified.
  • EGF Epidermal growth factor
  • IGF-I Insulin-like growth factor-I
  • Osteogenic protein-1 is a bone growth factor already approved for human use in repairing bone, cartilage, and eye tissue. Although OP-1 may play a key role in the embryonic development of human kidneys, it is not clear how it works to help repair adult kidney cells. It is possible that OP-1 and other autocrine kidney growth factors together could have complementary mechanisms of action.
  • kidney epithelial cells Some of the factors cited above are released by kidney epithelial cells and are capable of stimulating growth of the cells in an autocrine manner.
  • monkey kidney (BSC-1) cells respond to culture medium with a reduced concentration of potassium by releasing the "Low Potassium Growth Factor,” and respond to a reduced concentration of sodium by releasing the "Low Sodium Growth Factor” (Mordan and Toback, 1984; Walsh-Reitz et al, 1986; Toback et al. 1992b and 1995).
  • the invention includes the family of proteins and peptides including those having amino acid sequences of novel mitogenic proteins termed Wound Growth Factor (WGF), and its NH 2 - terminal peptides which also stimulate growth of kidney epithelial cells.
  • WGF Wound Growth Factor
  • Bioactive WGF is defined herein as a factor that stimulates mitogenic activity in cultured renal cells and is generally what is meant by “WGF” herein.
  • WGF includes peptides of various lengths, derived from the parent molecule as long as they have mitogenic activity.
  • Suitable "WGF-derived peptides” are those in which amino acid substitutions, additions or deletions occur, but the peptides stimulate mitogenic activity, and their action is blocked by the pentapeptide YPQGN, or any other peptide that blocks activity. It is believed that at least the pentapeptide YPQGN blocks access to a cellular WGF receptor.
  • a preferred hexamer (6-mer) sequence, NH 2 -tyrosine/cysteine-proline-glutamine-glycine-asparagine-histidine-COOH (Y/CPQG ⁇ H) is generally included in the peptides. (A slash between amino acids at a position indicates either one is present.)
  • the invention is directed to biological growth-promoting proteins and peptides derived from an amino acid sequence, initially referred to as characterizing a protein designated Wound Growth Factor (WGF) because of the manner of production in culture of the basic "factor". Further analysis initially revealed factors of two molecular weights,
  • An embodiment of a novel peptide of the present invention derived from WGF is a potent mitogen for monkey kidney epithelial cells in culture, the peptide including a 14 amino acids sequence, AQPYPQGNHEASYG. This 14-amino acid
  • proteins is the term used for molecules of about 50 amino acids or greater. Peptides are smaller. peptide (14-mer) is called “14-Ser” to indicate that it has a serine residue at position 12. Compared to other known renal growth factor mitogens, this peptide containing the sequence YPQGNH or CPQGNH, or native full-length WGF has a mitogenic effect that is either additive with, equivalent to, or more potent than other known factors: e.g., epidermal growth factor, acidic fibroblast growth factor, basic fibroblast growth factor, insulin-like growth factor-I, ⁇ 'asopressin, or calf serum.
  • epidermal growth factor e.g., epidermal growth factor, acidic fibroblast growth factor, basic fibroblast growth factor, insulin-like growth factor-I, ⁇ 'asopressin, or calf serum.
  • the naturally-occurring factor is released into culture medium when a kidney cell monolayer is subjected to mechanical scrape wounding with a pipette tip.
  • WGF naturally-occurring factor
  • a source of cells which releases the factor is the BSC-1 cell line (nontransformed African green monkey kidney epithelial cells) (ATCC CCL 26/BS-C-l).
  • BSC-1 cell line nontransformed African green monkey kidney epithelial cells
  • ATCC CCL 26/BS-C-l ATCC CCL 26/BS-C-l.
  • the appearance of growth-promoting activity after wounding is likely mediated by the proteolytic activation of an inactive precursor of WGF.
  • Evidence for this is that preincubation of the cells for 10 minutes with each of the following diverse protease inhibitors prevented the appearance of growth-promoting activity after wounding: aprotinin, phenylmethylsulfonylfluoride (Sigma) (PMSF), antipain.
  • PMSF phenylmethylsulfonylfluoride
  • TLCK L-l-chloro-3-(4-tosylamido)-7-amino-2-heptanone-hydrochloride
  • TLCK L-l-chloro-3-(4-tosylamido)-7-amino-2-heptanone-hydrochloride
  • TLCK L-l-chloro-3-(4-tosylamido)-7-amino-2-heptanone-hydrochloride
  • ⁇ -macroglobulin
  • HPLC-purified WGF does not appear to be a protease because it did not exhibit proteolytic activity when assayed using Protease Substrate Gel tablets (BioRad).
  • WGF exhibits a growth-promoting activity after it is released into the culture medium of scrape-wounded kidney epithelial cells such as BSC-1 cells. Isolation and purification of components responsible for this growth-promoting activity revealed that the components behave on sodium dodecylsulfate (SDS)-polyacrylamide electrophoresis as if they had a relative molecular mass (M r ) of 22 and/or 45 kilodaltons (kDa). Further analysis revealed that WGF is a protein that is a mitogen for monkey kidney BSC-1 cells, but not for
  • 3T3 fibroblasts Release of WGF also appears to be relatively kidney epithelial cell-type specific in origin, because it appears after wounding BSC-1 cells in culture, but not after wounding fibroblasts in culture.
  • an aspect of the present invention is a protein designated "WGF" having the following characteristics: a) an estimated molecular weight of about 45 and/or 22 kDa, said estimate obtained by electrophoresing the HPLC-purified protein on an SDS-polyacrylamide gel; b) capable of stimulating mitogenic activity when in contact with cultured cells; and c) released by BSC-1 cells in culture by scrape wounding.
  • Another WGF protein has an estimated molecular weight of about 22 kDa, said estimate obtained by electrophoresing the HPLC-purified protein on an SDS-polyacrylamide gel and obtaining a partial amino acid sequence at its amino terminal end as follows: NH 2 -alanine-glutamine-proline-tyrosine/cysteine- proline- glutamine-glycine-asparagine-histidine-glutamic acid-alanine- threonine-serine- serine-serine-phenylalinine-COOH.
  • a protocol suitable to purify WGF from conditioned cell culture medium utilizes ultrafiltration, heparin-affinity chromatography and reversed-phase (RP) high-performance liquid chromatography (HPLC). 6,400 fold purification is achieved, although the yield of WGF protein is extremely low, usually in the range of about 50 ng protein per liter of conditioned medium.
  • the size of bioactive WGF was defined by electrophoresing HPLC-purified WGF on SDS gels in parallel with standard proteins (i.e., proteins of known sizes), slicing the gel into 2-mm wide gel fragments, eluting each fragment in buffer, and then assaying the eluate for mitogenic activity using cultures of BSC-1 cells.
  • standard proteins i.e., proteins of known sizes
  • Amino acid compositional analysis of material that formed the sharp peak confirmed the protein character of WGF.
  • Microsequencing revealed the first 16 amino acids of the amino NH 2 -terminus of the 22 kDa isoform: NH 2 -alanine- glutamine-proline-tyrosine/cysteine-proline-glutamine-glycine-asparagine- histidine-glutamic acid-alanine-threonine-serine-serine-serine-phenylalanine- COOH.
  • peptides smaller than the 16 amino acid sequence also had strong mitogenic specific activity. This finding was quite significant because these small peptides: (1) are much less likely to be antigenic (i.e., they can be directly infused into another animal or human without being rejected by the immune system), and (2) they can be readily prepared in large quantities and modified using a peptide synthesizer without first having to find a cDNA clone that encodes the entire 22 or 45 kilodalton protein, and then expresses the recombinant protein.
  • synthetic peptides were produced that express the mitogenic activity.
  • a synthetic peptide whose sequence is based on the first eleven amino acid residues of the 22 kDa protein and exhibits mitogenic activity.
  • other polypeptides that are short peptide domains of the factor are also within the scope of the present invention.
  • An hexamer was the smallest peptide which still maintained mitogenic activity (YPQGNH or CPQGNH).
  • a peptide comprising an amino acid sequence of NH 2 -tyrosine/ cysteine- proline-glutamine-glycine-asparagine-histidine-COOH is suitable for the practice of the invention.
  • the peptide has a length of from 7 to 16 amino acids, but other lengths are also suitable if the mitogenic and/or antigenic function is preserved.
  • Both transforming growth factor-beta 2, and a synthetic 5-amino acid peptide having the sequence YPQG ⁇ block the mitogenic effect of AQPYPQGNHEASYG.
  • ARF acute renal failure
  • Mercuric chloride given subcutaneously was used to induce ARF in rats, and a solution of each peptide was evaluated for its capacity to enhance survival and speed recovery of renal function, assessed by measuring the serum creatinine concentration during the ensuing 7 days.
  • a peptide 100 ⁇ g having the sequence AQPYPQGNHEASYG, s.c, 1 hour after administration of mercuric chloride significantly improved recovery of renal function two days later and improved survival after three days. Beneficial effects of the peptide on survival and recovery of renal function were also observed when it was administered 16.5 hours after or 24 hours before induction of the nephrotoxic ARF syndrome.
  • Suitable peptides for the practice of the invention include:
  • PY/CPQGNHEA QPY/CPQGNH; PY/CPQGNHE; Y/CPQGNHEA; PY/CPQGNH;
  • Y/CPQGNHE Y/CPQGNHEATSSSF; Y/CPQGNHEATSSS; Y/CPQGNHEATSS; Y/CPQGNHEATS and
  • YPQGNH or CPQGNH are each a mitogenic fragment of protein.
  • Variants (isoforms) of the various WGF-derived NH 2 -terminal peptides or full-length WGF protein can differ in their amino acid sequence or in ways that do not involve sequence modifications such as post-translational modifications (e.g., glycosylation), or both.
  • Variants in amino acid sequence are generated when one or more amino acids of the NH 2 -terminal peptides or WGF protein is substituted with a different naturally-occurring amino acid, an amino acid derivative, or non-native amino acid.
  • variants include native WGF protein isoforms, biologically-active peptides of naturally-occurring WGF protein, and synthetic peptides whose sequences differ from the wild type sequence by one or more conservative amino acid substitutions, which typically have minimal influence on the secondary structure and hydrophobic nature of the protein or peptide.
  • Variants may also have sequences that differ by one or more non-conservative amino acid substitution, deletions or insertions that do not abolish the biological activity, that is, the mitogenic activity of the WGF peptides or full-length protein.
  • Functionally equivalent peptides may be constructed by substituting equivalent amino acids, and using the mitogenic assay to demonstrate that the molecule produced stimulates growth of BSC-1 cells by 15 to 35% compared to a functionally inert control peptide.
  • Peptides constructed with these "equivalent” or “conservative” substitutions may stimulate, inhibit, or have no effect of renal epithelial cell growth.
  • a guide to "conservative substitutions" is presented in Table 2. Syntheses of peptides with substitutions is readily performed by those of skill in the art, and the mitogenic assay is easy to perform. Therefore, peptide?. within the scope of the invention are readily determined.
  • Conservative alterations typically include the substitution of one amino acid for another with similar characteristics such as substitutions within the following pairs or groups: valine, glycine; glycine, alanine; valine, isoleucine; aspartic acid, glutamic acid; asparagine, glutamine; serine, threonine; lysine, arginine; and phenylalanine, tyrosine.
  • the non-polar (hydrophobic) amino acids include alanine, leucine, isoleucine, valine, proline, phenylalanine, tryptophan and methionine.
  • the polar neutral amino acids include glycine, serine, threonine, cysteine, tyrosine, asparagine and glutamine.
  • the positively-charged (basic) amino acids include arginine, lysine and histidine.
  • the negatively-charged (acidic) amino acids include aspartic acid and glutamic acid.
  • Glutamic Acid E D-Glu, D-Asp, Asp, Asn, D-Asn, Gin, D-Gln
  • Lysine K D-Lys, Arg, D-Arg, homo-Arg, D-homo-Arg, Met, D-Met, He, D-Ile, Orn, D-Orn
  • Tyrosine D-Tyr Phe, D-Phe, L-Dopa, His, D-His Valine V D-Val, Leu, D-Leu, He, D-Ile, Met D-Met
  • composition comprising the proteins or peptides described herein is within the scope of the invention.
  • a method for producing a protein or peptide of the present invention includes the steps of: a) culturing kidney epithelial cells in media, b) scrape-wounding the cells in culture, and c) obtaining the protein from the conditioned medium.
  • a recombinant DNA method of making a protein or peptide of the present invention includes the following steps: a) obtaining a nucleotide sequence encoding the protein or peptide; and
  • the peptides of the present invention can also be prepared directly on a peptide synthesizer, without recourse to cellular or molecular biological techniques.
  • Antibodies to WGF and derived peptides is an aspect of the present invention. Availability of each antibody provides a diagnostic tool to measure the amount of the factor and its derived mitogenic peptides in urine, blood and tissue.
  • New diagnostic insights are facilitated in patients receiving drugs with nephrotoxic potential during treatment of infections or malignancies, and in individuals with renal injury or neoplasia.
  • Such an antibody may also be used to detect renal cancer in the remnant kidneys of patients undergoing chronic peritoneal dialysis and/or hemodialysis.
  • the antibodies are for example, directed to a protein or peptide including the active site, that generally includes Y/CPQGNH.
  • a diagnostic kit is used to measure the quantity of a ' WGF protein or a mitogenic peptide derived therefrom, in a biological sample to detect acute renal injury or the early onset of kidney disease, monitor treatment of renal cell cancer, or recognize the conversion of benign renal cysts in chronic dialysis patients to carcinomas or cystadeno carcinomas.
  • the kit includes in separate containers: a) an antibody to WGF or to a mitogenic peptide derived therefrom; and b) a means for detecting a specific complex between the WGF protein or a mitogenic peptide, and the antibody.
  • Controls and buffers may also be included.
  • the invention includes the use of the peptides in preparing a composition for medical treatment of kidney disease, said preparation comprising obtaining the peptides and adding to them a suitable carrier.
  • suitable carriers are well-known in the art.
  • the new kidney growth factor proteins and peptides of the present invention, and antibodies directed to them, have diverse uses in clinical medicine.
  • the WGF peptides are useful for stimulating kidney cell growth, a characteristic useful for treatment of acute renal failure. It is particularly desirable to speed recovery in patients with acute renal failure, especially those receiving cadaveric kidney transplants that have reduced growth potential. Infusion of the protein or peptides into patients is directed to shortening the duration of the acute renal failure episode which would increase patient survival, and reduce the number of days required for hemodialysis treatment during the renal failure syndrome.
  • the peptides also provide an in vitro standard of comparison for other candidate growth factors. One or a plurality of peptides may be used.
  • WGF will have a role as a therapeutic agent to slow the progression of established kidney diseases such as chronic glomerulonephritis or interstitial nephritis.
  • WGF and its receptor appears to be on the surface of renal epithelial cells. If WGF is found to be a ligand for receptors on the surface of specific renal epithelial cell types along the nephron, it is to be considered in cancer chemotherapy. If it is found to be cancer cell-type specific, the growth factor could be conjugated with a cellular toxin, a radioactive isotope, or cytotoxic antibody to produce powerful new chemotherapeutic agents.
  • a method of treating a person with acute renal failure includes: a) preparing a pharmacologically effective amount of native WGF protein or WGF-derived peptide in a suitable diluent; and b) administering the preparation to the person.
  • the WGF may be ligated to a cytolytic ligand, e.g. a toxin.
  • the invention also relates the use of a protein or peptide described herein to obtain a composition useful in treating a person with acute renal failure.
  • Multimers may be even more effective in increasing cellular mitogenic activity, e.g. as the 40-mer disclosed herein.
  • Multimers may be formed from homogeneous peptides, e.g. multimers of the hexapeptide Y/CPQGNH, or may be combinations of peptides from the WGF.
  • a composition may include at least one multimer of a WGF-derived peptide, made from one of the group consisting of the hexapeptide NH 2 - Y/CPQGNH-COCH, or the first 10 amino acids of the 22-kD and 45-kD WGF protein (AQPYPQGNHE), or the 14-Ser peptide (AQPYPQGNHEASYG), or multimers of other WGF sequences, or combinations of any of the peptides disclosed herein.
  • AQPYPQGNHE the first 10 amino acids of the 22-kD and 45-kD WGF protein
  • AQPYPQGNHEASYG 14-Ser peptide
  • the composition may include at least one WGF-derived peptide in which one or more amino acids are replaced with a naturally-occurring amino acid, an amino acid derivative, or a non-native amino acid, so long as the resulting variant retains its mitogenic activity.
  • a suitable WGF-derived peptide may have an amino acid sequence that differs by at least one amino acid substitution, deletion, or insertion from another WGF-derived peptide having mitogenic activity.
  • compositions including a structural homolog of WGF protein whose nucleotide and amino acid sequences have at least 80% homology and exhibit mitogenic activity.
  • compositions including at least one structurally altered isoform of WGF protein that is posttranslationally modified by one of the following: glycosylation, sulfation or myristilation, retain mitogenic activity.
  • a composition of the present invention may also include a cell surface receptor(s) to which native WGF protein and WGF-derived peptides bind to initiate mitogenic signal transduction.
  • a composition may include the WGF protein or WGF-derived peptides in combination with other known growth factors and/or nutrients.
  • compositions of the present invention are useful for methods of treatment of kidney failure or dysfunction, by a) preparing a pharmacologically effective amount of native WGF protein or WGF-derived peptide in a suitable diluent, optionally, with other growth factors and/or nutrients; and b) administering an effective amount of the preparation to the person with the kidney problems.
  • FIG. 1 illustrates growth-promoting activity of wound growth factor-derived peptides on growth of BSC-1 cells.
  • FIG. 2A illustrates enhanced survival and FIG. 2B shows renal functional recovery of rats given a WGF-derived peptide (14-Ser) after mercuric chloride-induced acute tubular necrosis.
  • A Values are means ⁇ standard error. *, Student's t-test, P ⁇ 0.034.
  • B Percent survival is calculated as the number of rats alive divided by total number alive and dead; *, chi squared, P ⁇ 0.050.
  • FIG. 3 A illustrates enhanced survival and FIG. 3B renal functional recovery of rats given WGF-derived peptide (14-Ser) after ischemic acute renal failure induced by bilateral kidney pedicle clamping.
  • Percent survival is the number of rats alive divided by the total number alive and dead.
  • Values are means ⁇ standard error. *, Student's t-test, PO.032.
  • kidney epithelial cells released an autocrine factor into the medium after wounding
  • conditioned culture medium was removed from the culture dish after scrape-wounding a monolayer of BSC-1 cells. An aliquot was assayed for any growth-promoting activity on a nonwounded "detector" culture (1.2 x 10 cells per 55-mm dish).
  • WGF Wound Growth Factor Mitogenic Activity
  • Pentosan polysulfate (Sigma Chemical, St. Louis) which is known to block the activity of heparin-binding growth factors such as acidic and basic fibroblast growth factors, also blocked activity of WGF suggesting that it is a cationic molecule.
  • Certain mitogenically-active fractions of WGF eluted from a C reversed-phase HPLC column also bind to concanavalin A-Sepharose 4B (Pharmacia LKB), and are eluted by alpha-methyl mannoside, suggesting the factor contains carbohydrate.
  • WGF WGF, Heparin, and Other Growth Factors
  • heparin (Sigma) augments the mitogenic activity of WGF but inhibits aFGF when each component is added to BSC-1 cells
  • keratan sulfate a glycosaminoglycan component of the extracellular matrix
  • the mitogenic effects of maximal concentrations of WGF and aFGF are additive
  • the size of WGF is about 45 kDa whereas aFGF is about 16 kDa.
  • WGF also differs from basic FGF (bFGF) in that (1) bFGF (Gibco/BRL) elutes from an heparin affinity column at 1.5 to 1.6 M NaCl whereas WGF elutes at 0.4 to 1.0 M NaCl, and (2) the mitogenic activity of bFGF is 90% inhibited by 55% acetonitrile/ 0.1% (TFA) which has no effect on the activity of WGF. Furthermore, aFGF and bFGF mRNA are not detected by Northern blotting of BSC-1 cells, indicating that genes encoding these growth factors are not expressed by the cells. The mitogenic effects of maximal concentrations of partially-purified WGF and epidermal growth factor (EGF, Promega) are also additive, indicating that they probably exert their mitogenic effects by different receptors and signaling pathways.
  • bFGF Gibco/BRL
  • WGF resides on the cell surface, it appears to be protected from degradation by trypsin, possibly by carbohydrate residues linked to its protein backbone, and/or by associating with glycosaminoglycans adherent to the plasma membrane (glycocalyx).
  • trypsin a proteolytic enzyme
  • the enzyme was previously shown to have the capacity to destroy WGF activity.
  • soybean trypsin inhibitor (10 ⁇ g/ml) was added to neutralize the enzyme. When the cell monolayer was subsequently wounded, full biologically active WGF was released into the culture medium indicating that exogenous trypsin had not destroyed growth factor associated with the cells.
  • WGF does not appear to be stored by the cells in extracellular matrix (ECM). This conclusion is based on the following experiment. A confluent monolayer of BSC-1 cells is detached from ECM by addition of EGTA (J.T.
  • the mitogenic potency of partially-purified WGF is equivalent to the mitogenic potency of about 5% calf serum, or 20 pg/ml aFGF, or 20 pg/ml basic FGF, or 15 ng/ml EGF, using assays disclosed herein.
  • the mitogenic potency of the 14-amir ⁇ o acid'peptide AQPYPQGNHEASYG having a serine residue at position 12 was compared to growth factors and other mitogenic signals for monkey kidney epithelial cells of the BSC-1 line.
  • the previously identified maximal mitogenic concentration of each growth-promoting signal was employed, and compared to the
  • WGF-derived peptide at concentrations from 0 to 0.5 ⁇ g/ml.
  • EGF EGF
  • IGF-I acidic fibroblast growth factor
  • FGF-1 acidic fibroblast growth factor
  • FGF-2 basic fibroblast growth factor
  • vasopressin 75 pg/ml
  • calf serum calf serum (0-1%)
  • high potassium medium 5 mM added KCI, final concentration 10.4 mM
  • high sodium medium 25 mM of NaCl added, final concentration 180 mM
  • Nontransformed monkey kidney epithelial cells of the BSC-1 line were grown to confluence in Dulbecco's modified Eagle's medium containing 1% calf serum and 1.6 ⁇ M biotin in 55-mm culture dishes at 38°C in a CO 2 incubator. When cells achieved a density of about 10 per dish, the spent medium was removed and replaced with fresh medium containing 0.5% calf serum and the 14-amino acid peptide (0.5 ⁇ g/ml). Additions of each of the mitogenic signals at maximal concentration were made to the culture medium. Four days later the number of cells in each culture was counted in an hemocytometer. Values obtained were the mean of 3 separate cultures. Doubling the calf serum concentration from Dulbecco's modified Eagle's medium containing 1% calf serum and 1.6 ⁇ M biotin in 55-mm culture dishes at 38°C in a CO 2 incubator. When cells achieved a density of about 10 per dish, the spent medium was removed and replaced with fresh medium containing 0.5% calf
  • the "14-Ser peptide" AQPYPQGNHEASYG increased cell number by
  • EGF 50 ng/ml
  • EGF alone stimulated growth by 31%) in the absence of "the 14-Ser peptide," and by 61%) in its presence, indicating that the two mitogens were additive.
  • IGF-I (50 ng/ml) stimulated growth by 20%; it was less potent than the
  • Acidic FGF 100 pg/ml
  • basic FGF 1,000 pg/ml
  • vasopressin 75 pg/ml
  • 14-Ser peptide which increased cell number by 25%.
  • Each of these known peptide growth factors was additive with the 14-Ser peptide peptide; acidic FGF by 44%; basic FGF, 41%; and vasopressin, 36%>.
  • the 14-Ser WGF-derived peptide is a potent mitogen because it is equivalent to, or more potent than, each of five known peptide growth factors for kidney epithelial cells.
  • the growth-promoting effect of the 14-Ser peptide was additive with each of the five growth factors suggesting that it acts by a different receptor and/or signal transduction pathway than they do.
  • the additive mitogenic effects suggest that the 14-Ser peptide, in combination with one or more of the known growth factors, could act in vivo to speed repair and regeneration of the injured kidney during acute renal failure.
  • each of the two ionic mitogenic signals were additive with the 14-Ser peptide mitogen.
  • Confluent monolayers of BSC-1 cells are prepared as herein and exposed to the 14-Ser peptide (0.5 ⁇ g/ml) for different amounts of time (0 to 30 minutes). At the end of the defined exposure period, culture medium containing the mitogen was aspirated, the monolayer was rinsed to remove nonadherent peptide, and fresh medium was added. Four days later the number of cells in the culture was counted.
  • a protocol to prepare one liter of WGF conditioned medium is described herein.
  • the usual yield of WGF protein is about 50 ng per liter as estimated by
  • Conditioned Media Preparation 100 cultures of BSC-1 cells are grown to confluence (6-8 x 10 cells) on plastic tissue culture dishes (Nunc) having a diameter of 10 cm in Dulbecco's modified Eagle's medium containing 2% calf serum. The medium is aspirated, and the culture is rinsed with phosphate-buffered saline (PBS) (Sigma) solution to remove medium and serum. Then 10 ml of PBS is added to each dish in preparation for wounding. A total of 5 wounds to the cell monolayer are rapidly made by scraping a 200 ⁇ L plastic pipet tip across the surface of the dish from edge to edge. About ten minutes later (9.5 minutes is preferred) the conditioned buffer is decanted into a plastic Nalgene beaker.
  • PBS phosphate-buffered saline
  • pooled conditioned buffer is sterile-filtered (CoStar, 0.2 ⁇ m pore size) to remove any debris or detached cells into silanized (Aquasil, Pierce) glass bottles (Wheaton).
  • the sterile conditioned buffer is diafiltered, desalted, and concentrated using a YM-30 disc membrane (Amicon) at 4°C. The concentrated material is then sterile filtered
  • the concentrate (300-400 ⁇ l) is loaded onto a C -reversed phase HPLC column (250 mm x 4.6 mm, particle size 5 ⁇ m) (Vydac), and is eluted with a gradient of acetonitrile (1-80%) in trifluoroacetic acid (0.1%) (TFA) for 50 minutes using a Beckman Gold Chromatographic System.
  • acetonitrile (1-80%) in trifluoroacetic acid (0.1%) (TFA)
  • TFA trifluoroacetic acid
  • At least 5 different protein peaks (monitored by absorbance at 214 nm) that exhibit mitogenic activity can be readily identified. However, the peak that elutes at ⁇ 55% acetonitrile routinely exhibits the most mitogenic activity and reproducibility in different isolates.
  • This eluate is collected by hand into a silanized Eppendorf tube, loaded onto a C 8 column (Vydac), and rechromatographed using the same acetonitrile/TFA gradient described above. Again the mitogenic activity elutes at ⁇ 55% acetonitrile. Growth-promoting activity and total protein content is monitored at each step during the purification process. Depending upon the number of liters of conditioned buffer processed, it may be necessary to run a second C 8 column to optimize separation of the peak of interest. This bioactive material is then reduced in volume using a vacuum concentrator (Savant), and subsequently loaded onto a 12.5% ⁇ SDS gel for electrophoretic separation.
  • Savant vacuum concentrator
  • the M r of WGF is estimated by comparison of its electrophoretic migration to that of standard proteins of known molecular size. Different proteins in the gel are visualized by staining with silver (BioRad), or after blotting onto a PVDF membrane (Millipore) and staining the blot with Coomassie blue dye (Gibco/BRL). More than one band usually appears. To determine which band represented the mitogenic form of WGF, an unstained nonreducing gel was sliced into 2-mm wide fragments after electrophoresis, and each was eluted for 18 hours with agitation at room temperature in PBS containing acetonitrile (3%) and bovine serum albumin (0.1%)).
  • A Ala, alanine C, Cys, cysteine D, Asp, Aspartic acid E, Glu, glutamic acid F, Phe, phenylalanine G, Gly, glycine H, His, histidine I, He, isoleucine K, Lys, lysine L, Leu, leucine M, Met, methionine N, Asn, asparagine P, Pro, proline Q, Gin, glutamine R, Arg, arginine S, Ser, serine T, Thr, threonine V, Val, valine W, Trp, tryptophan Y, Tyr, tyrosine M-NH 2 , methionine amide X, identity not pE, pyroglutamic acid determined
  • the first 10 amino acids are identical in each of the four sequence determinations, suggesting that the 22 kDa protein could be a fragment or breakdown product of the 45 kDa protein.
  • the different sequences of amino acids 12 to 14 in the 22 and 45 kDa proteins suggest that they could represent two WGF isoforms.
  • the NH 2 -Terminal Domain of WGF is Mitogenic For Kidney Epithelial Cells
  • MAPS multiple antigenic peptide system
  • the MAPS protein has a polylysine backbone that is attached to a resin at one end and has four branches at the other; each branch is ligated to one molecule of the 11 -mer peptide.
  • the MAPS peptide stimulated DNA synthesis and proliferation of monkey kidney epithelial cells of the BSC-1 line. Its maximal growth-promoting effect was similar to that of native WGF.
  • the growth-promoting effect of the 1 1-mer peptide and of wound conditioned buffer were not additive, suggesting that the 11-mer peptide stimulates cell proliferation by the same receptor and signaling pathway as does intact WGF.
  • the 11 amino acids of the NH -terminus represent a mitogenic domain of WGF, although other growth-promoting domains may be contained in the native 45 kDa protein whose estimated length is about 400 amino acids.
  • FIG. 1 shows equivalent mitogenic dose responses of a synthetic 11-mer peptide, AQPYPQGNFIEA which represents native (22 kDa) amino-terminal WGF, and the most active hexapeptide synthesized of the present invention
  • the native sequence is preferred (see Table 3).
  • the "native" sequence is that found in the 22 or 45 kDa WGF as obtained from cultured cells.
  • the peptides are purified by reversed-phase HPLC on a Cig column using a gradient of acetonitrile (1-80%) in
  • Nontransformed monkey kidney epithelial cells of the BSC-1 line were grown to confluence in Dulbecco's modified Eagle's medium containing 1% calf serum and 1.6 ⁇ M biotin at 38°C in a C0 2 incubator. When cells achieved a density of about 10 per dish, the spent medium was removed and replaced with fresh medium containing 0.5% calf serum and different amounts of the two peptides. Four days later the number of cells in each culture was counted. Each value is the mean of 3 separate cultures.
  • Mitogenicity of WGF-Derived Peptides To delineate the sequence of the smallest peptide that could stimulate renal cell growth, synthetic peptides of different lengths were prepared (see below), and purified by reversed-phase HPLC on a C 18 column. Mitogenic activity was assessed in a culture of BSC-1 cells by counting the number of cells after exposure to a specified concentration (0.5 to 20 ⁇ g/ml) of peptide foi four days, and comparing the result to growth in the absence of added peptide.
  • WGF 11-mer NH 2 -A Q P Y P Q G N H E A-COOH
  • each of five shorter peptides (6 to 9 amino acids long) stimulated renal cell growth maximally to the same extent (25-30%) as did native WGF.
  • the following peptides (4 to 6 amino acids long) represent domains of
  • WGF 11-mer NH 2 - -A Q P Y P Q G N H E A- COOH
  • NH 2 -terminus of native WGF contains an hexapeptide sequence, NH 2 -tyrosine-proline-glutamine-glycine-asparagine-histidine-COOH, that is mitogenic for renal epithelial cells, as exemplified by the BSC-1 line.
  • Peptides of various lengths are also within the scope of the present invention, as long as the mitogenic hexamer sequence or its equivalent is included.
  • Peptides of various lengths may be used individually or combined in various ways for specific purposes. These possibilities include (NH 2 -terminus >COOH terminus):
  • PYPQGNHE YPQGNHEA PYPQGNH YPQGNHE These peptides may be combined with other amino acid sequences at either end or both ends (NH 2 -and-COOH). The amino terminus Y may be substituted by cysteine.
  • the strategy was to design and then chemically synthesize diverse peptides by substituting structurally related amino acids for those found in the native WGF sequence.
  • the peptide of interest was then purified on a reversed-phase 8 column HPLC as described herein using a gradient of 1-80% acetonitrile in 0.1% trifluoroacetic acid (TFA).
  • TFA trifluoroacetic acid
  • the purified peptide was then lyophilized to remove the acetonitrile and TFA and the lyophilized powder was weighed, dissolved in buffer and added to the culture medium to measure its effect on the growth of monkey kidney epithelial cells as described herein.
  • K % concentration in micromoles
  • the length of the 14-mer AQPYPQGNHEAAYG provoked interest about the three-dimensional structure of the peptide. Circular dichroism was carried out and revealed a spectrum consistent with a beta-pleated sheet conformation.
  • the potency of the 11 -mer peptide AQP YPQGNHEA is similar to that of the synthetic hexapeptide YPEGNH (K. /2 ⁇ 0.3 ⁇ M) which has a single substitution: glutamic acid (E) replacing the native glutamine (Q). Therefore, some substitutions produce peptides with at least as effective mitogenic activity. However, certain conservative modifications of the
  • 6-mer sequence result in drastic reductions in potency: replacement of the tyrosine (Y) residue with phenylalanine (F), substitution of asparagine (N) with aspartic acid (D) or lysine (K), or amidation of the carboxy-terminus.
  • hexapeptides YPQGNH or YPEGNH have a high potency for renal epithelial cells was obtained by defining the time required for interaction between peptide and cells for irreversible commitment to accelerated proliferation.
  • a solution containing the peptide of interest was added to the cell monolayer; culture medium was then aspirated at a specified time thereafter. Then fresh medium without the peptide was added and the number of cells was counted four days later.
  • Contact of the cells with the peptide YPQGNH for 2 minutes resulted in maximal growth-promoting activity , whereas the peptide could be completely washed off the cells at earlier times (0.5, 1, or 1.5 minutes) without stimulating growth.
  • keratan sulfate enhances the mitogenic potency of not only native WGF protein but WGF-derived peptides as well.
  • Alignment between the 14 amino acids of the NH -terminus of WGF and the bombesin molecule is limited to the consecutive GN residues (amino acids #7,8 in the 14 amino acid active peptide of WGF; #5,6 in bombesin), and an A residue (amino acid #11 in WGF; #9 in bombesin).
  • Previous reports (Broccardo et al,
  • WGF WGF-derived hexapeptide YPQGNH
  • GRP-derived hexapeptide YPRGNH is at most borderline mitogenic (10% stimulation) for renal epithelial cells and is not reported to be necessary for mitogenic stimulation of fibroblasts.
  • the mitogenic hexapeptide derived from the NH 2 -term ⁇ nus of WGF differs in only a single amino acid (Q ⁇ >R) from an hexapeptide sequence in human and porcine GRP, YPRGNH (amino acids #15 to 20), a domain that is not known to be mitogenic (Heimbrook et al, 1988).
  • YPQGNH amino acids #4 to 9 in the WGF sequence
  • WGF-derived hexapeptide YPQGNH
  • the shortest synthetic peptide with mitogenic activity was initially found to have the sequence NH 2 - tyrosine-proline-glutamine-glycine-asparagine-histidine- COOH (YPQGNH).
  • This hexapeptide represents amino acids in positions #4 to #9 of the amino-terminus of WGF.
  • the amino acid identified in position #4 of each of the two WGF isoforms by microsequencing could be either a cysteine (C) or a tyrosine (Y) residue.
  • a tyrosine or cysteine residue in the hexameric cassette (Y/CPQGNH) of WGF-derived synthetic peptides of different lengths (e.g. , 6 to 40 residues) described herein can fully support mitogenic function in kidney epithelial cells.
  • Synthetic peptides that increase mitotic activity in an equivalent position containing either of these two amino acids, or others (Table 2), are produced and used to improve survival and speed functional recovery after acute renal failure.
  • WGF human kidney epithelial cells
  • Micro-sequencing of the NH 2 -termini of these proteins suggested that they may be isoforms because the first 10 amino acids of each were identical. A total of 16 amino acids were identified at the NH 2 -terminus of the 22 kDa isoform, and 14 for the 45 kDa isoform. However, for the 45 kDa isoform, the amino acid at position 11 was not identified, and at position 12, alanine or serine were equivalent designations. At position 4, tyrosine or cysteine were equivalent designations.
  • Peptides of various lengths are within the scope of the present invention, as long as the mitogenic hexamer sequence, NHrtyrosine-proline-glutamine-glycine- asparagine-histidine-COON (YPQGNH) is included.
  • Amino acid replacements were identified in the amino-terminus of native WGF that could maximize the growth-promoting activity of the peptide for use in studies of its efficacy in treatment of acute renal failure in a rat model of this syndrome.
  • the strategy was to design and then chemically synthesize diverse peptides by substituting structurally related amino acids for those found in the native WGF sequence.
  • the peptide of interest was then purified on a reversed-phase C 18 HPLC column using a gradient of 1-80%) acetonitrile in 0.1 % trifluoroacetic acid (TFA).
  • the purified peptide was then lyophilized to remove the acetonitrile and TFA and the lyophilized powder was weighed, dissolved in buffer and added to the tissue culture medium to measure its effect on growth of monkey kidney epithelial cells.
  • To compare the relative potency of different peptides only those molecules that stimulated growth maximally after 4 days in culture by 25-30%) were analyzed further by defining their concentration-dependence. A value termed the K>/ 2 , was used. This term is defined herein as the peptide concentration in micromoles ( ⁇ M) at which the growth-stimulating effect is one-half the concentration at which maximal proliferation is observed. The lower the value, the greater the mitogenic potency of the peptide.
  • the glycosaminoglycan keratan sulfate was added at a concentration of 10 ⁇ g/ml the mitogenic potency of 14-Ser was enhanced because the K./ 2 fell to 0.067 ⁇ M.
  • the glycosaminoglycan heparin, added at a concentration of 1 ⁇ g/ml was even more effective, reducing the Ky.
  • glycosaminoglycan AAG
  • the stimulatory effect of glycosaminoglycans was mediated by formation of a peptide-GAG complex via ionic bonds (cationic histidine of peptide to anionic sulfate of either GAG) or by hydrogen bonding (hydroxyl groups of serine/tyrosine of peptide to oxygen residue of GAG carbohydrate).
  • the peptide-GAG complex could stabilize/facilitate binding of the peptide to its receptor on the cell surface, as has been proposed to explain the enhanced mitogenic effect of acidic fibroblast growth factor (FGF- 1 ) with heparin that has been observed with diverse types of cells.
  • FGF- 1 acidic fibroblast growth factor
  • an 11 amino acid peptide containing this SYG sequence was required for maximal mitogenesis
  • an 11 -mer peptide with the sequence YPQGNHEASYG was synthesized, purified, and then assayed for activity.
  • 10 / . was 0.166 ⁇ M in the absence or presence of heparin, indicating that the full 14 amino acid length was required for the maximal mitogenic effect.
  • the 14-amino acid peptide (14-Ser), because of its high mitogenic potency and relatively short length, was chosen for use in the treatment of rats with mercuric chloride-induced acute renal failure.
  • the 11 amino acids of the NH 2 -terminus of WGF were used to prepare two different conjugated peptide antigens.
  • KLH keyhole limpet hemocyanin
  • the MAPS protein and KLH-conjugat were used to immunize rabbits, chickens, and a sheep.
  • the antibody that results from these strategies serves to detect native WGF protein in urine, serum, and tissue in patients, with acute or chronic kidney diseases, and renal cell cancer. It could also be used to obtain a cDNA clone encoding WGF by immunoscreening a kidney epithelial cell cDNA library in ⁇ gtl 1.
  • WGF WGF-derived neurotrophic factor
  • a bacterial expression system may prove suitable, but if carbohydrate is definitively detected and shown to be required for full activity, then a mammalian expression system such as Chinese Hamster Ovary (CHO) cells would be more appropriate.
  • glycosylation of the protein is not required for mitogenic activity.
  • glycosylation could prove to be an important determinant in modulating the turnover (half-life) of the protein in vivo. This is the case for erythropoietin, for example.
  • a nucleotide sequence encoding for at least a mitogenic hexamer of the present invention is prepared, linked to suitable regulatory elements, and incorporated into an expression vector.
  • a host cell is transformed with the vector, and the host is placed in conditions suitable for expression.
  • the recombinant protein is isolated from the culture medium by using an antibody-affinity column prepared by conjugating an antibody to WGF to an appropriate matrix. This preparative strategy should yield large quantities of the recombinant protein.
  • sufficient amounts of the NH 2 -terminal 14-Ser, 11 amino acid peptide, the hexapeptide Y/CPQGNH, or other peptides expressing equivalent mitogenic potency can be prepared by conventional peptide synthesis.
  • the mitogenic potency of the peptides prepared by recombinant or chemical synthetic strategies can be assessed by measuring the capacity of an aliquot of the product to stimulate growth of BSC-1 cells. The expected response is a 20 to 35% increase in cell number after 4 days in confluent cultures compared to that observed in control cultures. Detailed techniques to produce WGF by recombinant systems are known to those of skill of art.
  • In vitro and in vivo models of acute renal failure are useful to study two major biological characteristics of wound repair: cell migration and proliferation. These models are suitable for analyzing the effects of WGF and its peptides of the present invention.
  • i. In Vitro model scrape-wounding of monolayer cultures of renal epithelial cells to simulate injured renal tubular epithelium.
  • kidney function during ARF is monitored by measurements of the concentration of serum creatinine and blood urea nitrogen (BUN) on a daily basis. These measurements provide estimates of glomerular filtration in the kidney which is one of its major functions. Creatinine enters the serum from muscle where it is released constantly as a consequence of the metabolic turnover of creatine phosphate, whereas the BUN is the end-product of total body protein turnover. Both molecules make their way into the blood and because of their small size are excreted in the urine. Thus the extent to which they accumulate in the blood and are not excreted in ARF provides a guide to the extent of kidney injury. Significant recovery of kidney function is indicated by a reduction in serum creatinine concentration.
  • Renal cell cancer is often a slow growing condition that results in widespread metastases to distant sites in the body making successful treatment difficult.
  • Studies using radioactive WGF permit its receptor on renal cells to be identified and isolated; antibodies directed against the receptor are then prepared.
  • WGF WGF
  • WGF a specific WGF peptide that exhibits binding to the receptor and can thereby be used to deliver an anticancer agent to the proliferating cells of interest.
  • anticancer agents comprise WGF or a specific WGF peptide or peptides conjugated to a toxin, cyto lytic antibody, or a radioisotope.
  • EPO erythropoietin
  • a typical dose of 14-Ser peptide for a 70-kg patient with ARF would be about 35 mg (100 ⁇ g per 200 gm body weight), administered by slow intravenous infusion.
  • the antibody to native WGF is prepared as disclosed herein and used to determine the concentration of the growth factor in urine and blood. Distribution of WGF in different types of renal cells along the nephron is determined. The concentration of the growth factor in either blood or urine or both could increase as a result of renal injury. If the grov/th factor is excreted in the urine as is epidermal growth factor, it may be possible to determine if renal injury leads to increased urinary excretion of the new factors. If so, enzyme-linked immunosorbent assay (ELISA) kits to detect WGF are used to rapidly diagnose early renal injury prior to a fall in glomerular filtration rate which is not detectable with conventional laboratory tests until more than 50% of kidney function is lost.
  • ELISA enzyme-linked immunosorbent assay
  • An antibody to WGF is incorporated into a diagnostic ELISA kit designed to detect the appearance of growth factor in blood and urine of patients with renal injury or neoplasia.
  • an ELISA kit could provide a new early detection system for these lesions.
  • Such a diagnostic kit could also be used in asymptomatic but high-risk individuals. Renal cancer is now difficult to detect early because it tends to be asymptomatic until the tumor has grown to significant size or has metastasized widely.
  • Analogs of the growth factor are developed to maximize the growth-promoting effect of WGF by optimizing specific binding to renal epithelial cell receptors.
  • Inhibitors that block the biological action of each factor by binding to receptors on the cell surface are also useful.
  • Such inhibitors include pentapeptides such as YPQGN and PQGNH.
  • Development of a synthetic or recombinant product that is resistant to degradation would prolong pharmacological activity in vivo.
  • Example 1 14-Ser Peptide is Effective in the Treatment of Nephrotoxic Acute Renal Failure
  • Nephrotoxic and ischemic acute renal failure (ARF) induced experimentally in rats have long been used to model this syndrome in humans.
  • ARF ischemic acute renal failure
  • 14-Ser a WGF-derived NH 2 -terminal peptide
  • acute tubular necrosis was induced by injecting a solution of mercuric chloride (in normal saline) subcutaneously into rats at a dose of 2.25 mg per kilogram body weight.
  • Male rats weighed 200-225 gm at the start of the experiment. This dose was used because preliminary experiments indicated it resulted in survival of 25-50% of the animals 7 days later.
  • Blood was obtained from the tail vein each day and the concentration of creatinine in the serum was measured and used as an index of renal function.
  • An increase in serum creatinine concentration signals a decline in renal function because the injured kidney is unable to excrete endogenous creatinine in the urine so it accumulates in the blood.
  • the synthetic peptide AQPYPQGNHEASYG (14-Ser) (dissolved in sterile 0.01%) bovine serum albumin in phosphate-buffered saline) was injected subcutaneously into rats to determine its effect on survival, recovery of renal function, and stimulation of DNA synthesis. Multiple different peptides were studied including 14-Ser, AQPYPEGNHEASYG (14-mer), AQPYPQGNHEATSSSF (16-mer), AQPYPQGNHEA (11-mer), and AQPYPEQGNHEA (11-mer). Different concentrations and times of administration were tested and compared. The results indicated that 14-Ser was the most effective WGF-derived peptide; it improved survival and recovery of renal function after mercuric chloride-induced ARF.
  • FIG. 2A Enhanced survival (FIG. 2A) and renal functional recovery (FIG. 2B) of rats given a WGF-derived peptide after mercuric chloride-induced acute tubular necrosis is shown.
  • Example 2 In Vivo Administration of 14-Ser peptide at 16.5 hours after induction of nephrotoxic ARF. Because physicians are unable to predict with certainty when acute renal failure will occur in patients, the serum creatinine concentration is measured to determine if kidney function has been compromised. After renal dysfunction is detected, treatment to reverse the condition is highly desirable. Thus, the utility of administered 14-Ser peptide in human ARF requires that it act favorably when impaired kidney function has been detected. The peptide increased the speed of recovery of renal function when administered to rats after the onset of nephrotoxic ARF under conditions that mimic the syndrome in humans. Mercuric chloride was given to each of 16 rats to induce renal injury.
  • the vehicle is sterile 0.01%) borine serum albumin in phosphate-buffered saline, pH 7.40.
  • 14-Ser peptide speeds recovery of kidney function when administered after nephrotoxic renal injury is clinically detectable.
  • BrdU a nonradioactive analog of thymidine that is incorporated into DNA was used to label nuclei.
  • a monoclonal antibody to BrdU and diamidobenzidene staining were used to detect nuclei undergoing DNA synthesis in histological sections of renal tissue.
  • BrdU was dissolved in 20% ethanol and was injected intra-peritoneally 23 hours after administration of mercuric chloride.
  • the kidneys were quickly perfused with a warm solution of phosphate-buffered saline via an aortic catheter to eliminate red blood cells from the organ and maintain patency of the renal tubules.
  • the capsule was removed from the kidneys which were then bisected longitudinally, and fixed in formahn for 4 hours, and then in 70%) ethanol. Tissue sections were prepared and BrdU-labeled nuclei were detected as described above.
  • Renal tissue from a rat given 14-Ser (100 ⁇ g) 24 hours before administration of mercuric chloride was also examined.
  • 1 hour of BrdU labeling was carried out 24 hours after mercuric chloride as described herein.
  • Microscopic examination revealed that many more labeled nuclei were present adjacent to the zone of tubular cell necrosis. This finding is important because it is in this boundary area of the cortex where regenerating cells are expected to undergo mitosis and then migrate into nephrons in the necrotic zone to replace cells that were irreversibly injured by the nephrotoxic insult.
  • the 14-Ser peptide appears to stimulate DNA synthesis in cells of regenerating nephrons after mercuric chloride-induced tubular necrosis, and by this mechanism, could thereby speed recovery of renal function and improve survival after ARF.
  • Example 3 14-Ser Peptide is Effective in the Treatment of Ischemic Acute Renal Failure
  • Ischemic acute renal failure is often caused by low blood pressure in the setting of severe hemorrhage, fluid loss (diarrhea, vomiting, diuretics), infection
  • WGF-derived peptides speeds repair of renal structure.
  • Standard assays in renal growth physiology and pathology are used to demonstrate that the growth-promoting (mitogenic) effect of a WGF peptide stimulates an increased number of kidney cells to initiate synthesis of DNA in preparation for cell division, as has been shown in tissue culture.
  • sections of kidney tissue from rats with mercuric chloride-induced ARF are prepared and inspected under light microscopy to compare the extent of renal injury and repair in animals that received WGF peptide and those that received a saline vehicle alone.
  • Another measure of the effect of WGF on recovery is an histopathological assessment based on detailed microscopic inspection of kidney tissue. A scoring system that grades the characteristic features of ARF and recovery is used to assess and compare kidney tissue from rats that did or did not receive treatment with WGF (Miller et al, 1994).
  • radioactive thymidine can be used to measure the capacity of WGF peptide to stimulate renal DNA synthesis after ARF.
  • radioactive thymidine is injected intraperitoneally 1 hour before death, and its incorporation into renal DNA is determined by subsequently extracting DNA from the tissue, and then measuring the amount of DNA by a chemical assay, and its radioactivity by scintillation counting.
  • Autoradiograms can also be prepared and used to determine which cells in kidney tissue have incorporated radioactive thymidine into DNA. All the techniques referred to are known to those of skill in the art (Coimbra et al, 1990).
  • Example 6 Inhibition of WGF-Derived Peptide Mitogenesis by TGF- ⁇ 2 and YPQGN Peptide To better understand the role of the 14-Ser peptide in renal cell growth regulation, agents that could inhibit its mitogenic effect were studied.
  • Transforming growth factor (TGF)- ⁇ 2 is an autocrine growth inhibitor secreted by BSC-1 cells that limits proliferation in culture. Exogenous TGF- ⁇ 2 was added to the culture medium to determine its capacity to inhibit the growth-promoting effect of 14-Ser. TGF- ⁇ 2 at a concentration of 1 ng/ml was sufficient to abolish the 25%) stimulation of growth induced by 14-Ser. At a TGF- ⁇ 2 concentration of 2 ng/ml, growth was inhibited by 30%> in the presence or absence of 14-Ser; at 10 ng/ml, inhibition was 60%. At a TGF- ⁇ 2 concentration of 6 ng/ml, exogenous 14-Ser up to 5 ⁇ g/ml did not reverse growth inhibition.
  • TGF- ⁇ 2 inhibits proliferation induced by diverse mitogens, a more specific inhibitor was sought.
  • studies of the 5 -amino acid WGF-derived peptides YPQGN and PQGNH were shown to inhibit the mitogenic effect of the 6-amino acid peptide, YPQGNH.
  • These pentapeptides do not alter growth when added to cells.
  • Cells were preincubated for 30 minutes with the pentapeptide YPQGN. The culture medium was then aspirated, the monolayer was rinsed, fresh medium was added, and the number of cells counted 4 days later.
  • Preincubation of cells with YPQGN inhibited the mitogenic effect of the 6-amino acid peptide.
  • preincubation with YPQGN for 10 or 30 minutes completely blocked the growth-promoting effect of each of the following peptides:
  • Y/CPQGNH described herein, bind to the same cell surface receptor, which also has high affinity for the pentapeptide YPQGN.
  • YPQGN the medium was then aspirated, and the monolayer was rinsed twice with fresh medium.
  • EGF 50 ng/ml
  • insulin-like growth factor-I 50 ng/ml
  • vasopressin 75 pg/ml
  • acidic fibroblast growth factor 100 pg/ml
  • basic fibroblast growth factor 1,000 pg/ml
  • Radioiodinated 40-mer is prepared and then added with heparin to cultures of BSC-1 cells.
  • the receptor is affinity labeled by cross-linking it to [ 125 I]40-mer by the action of disuccinimidyl suberate (Segarini et al, 1987).
  • the cell proteins are solubilized and separated by SDS-PAGE. Autoradiography enables visualization of the receptor and definition of its size.
  • receptor protein After a sufficient amount of receptor protein is isolated by this gel purification method, amino-terminal and internal amino acid sequence information will be obtained, oligonucleotide primers prepared, and the polymerase chain reaction used to obtain a cDNA clone encoding the receptor protein.
  • mice in each of three groups were given either 14-Ser (100 ⁇ g, s.c.) 1 hour after mercuric chloride (2.25 mg/kg s.c), EGF (20 ⁇ g, s.c.) 2 hours after the toxin, or the vehicle (s.c), and survival was monitored.
  • 14-Ser 100 ⁇ g, s.c. 1 hour after mercuric chloride (2.25 mg/kg s.c
  • EGF 20 ⁇ g, s.c. 2 hours after the toxin
  • vehicle s.c
  • WGF-derived peptide could prove particularly efficacious: (1) prior to surgical procedures in patients with a high risk of developing ARF (e.g., the elderly, neonates), (2) in patients given potentially nephrotoxic agents such as antibiotics for treatment of sepsis or antineoplastic agents, and (3) for perfusion of donor kidneys prior to their transplantation into new hosts.
  • ARF e.g., the elderly, neonates
  • potentially nephrotoxic agents such as antibiotics for treatment of sepsis or antineoplastic agents
  • perfusion of donor kidneys prior to their transplantation into new hosts.
  • a WGF-derived peptide such as 14-Ser or native WGF dissolved in an aqueous solution can be used to perfuse and protect and isolated (“ex vivo") ischemic, "donor" kidney from injury which may occur upon reperfusion of blood following reimplantation into a human recipient.
  • WGF can serve as an effective protectant when added to solutions employed to preserve cadaveric kidneys or kidneys removed from living donors and intended for transplantation.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Organic Chemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • Gastroenterology & Hepatology (AREA)
  • Biochemistry (AREA)
  • Biophysics (AREA)
  • Zoology (AREA)
  • Genetics & Genomics (AREA)
  • Medicinal Chemistry (AREA)
  • Molecular Biology (AREA)
  • Proteomics, Peptides & Aminoacids (AREA)
  • Toxicology (AREA)
  • Medicines That Contain Protein Lipid Enzymes And Other Medicines (AREA)
  • Peptides Or Proteins (AREA)

Abstract

L'invention concerne de nouveaux peptides de croissance dérivés de facteurs protéiques présentant des poids moléculaires d'environ 22 et 45 kDa qui stimulent l'activité mitogénique de cellules épithéliales mais non fibroblastiques, en particulier de cellules épithéliales rénales, à la fois in vitro et in vivo. Une source desdits facteurs est formée par des cellules épithéliales rénales en culture blessées par raclage. Des peptides synthétiques présentant 16 acides aminés au maximum, en particulier un hexapeptide, Y/CPQGNH maintiennent l'activité mitogénique. Le peptide AQPYPQGNHEASYG (14-Ser) a un effet efficace dans la guérison de l'insuffisance rénale aiguë à la fois néphrotoxique et ischémique chez les rats. Les caractéristiques de stimulation de croissance des protéines et des peptides de 22 et 45 kDa sont utiles pour le diagnostic de maladies du rein chez des patients et pour le traitement de ces maladies. Des séquences nucléotidiques qui codent ce facteur peuvent être utilisées pour développer des sondes permettant de localiser des facteurs similaires, pour identifier des troubles génétiques impliquant ce facteur, et pour produire ledit facteur par des procédés de recombinaison génétique. Les séquences nucléotidiques et des fragments de celles-ci sont également utiles pour le diagnostic et le traitement de troubles rénaux.
PCT/US1998/010574 1997-05-27 1998-05-22 Proteines et peptides stimulant la croissance in vitro et in vivo pour cellules epitheliales renales WO1999026974A1 (fr)

Priority Applications (6)

Application Number Priority Date Filing Date Title
CA002310677A CA2310677C (fr) 1997-11-20 1998-05-22 Proteines et peptides stimulant la croissance in vitro et in vivo pour cellules epitheliales renales
AU76935/98A AU745894C (en) 1997-11-20 1998-05-22 In vitro and in vivo growth-promoting proteins and peptides for kidney epithelial cells
DE69821025T DE69821025T2 (de) 1997-11-20 1998-05-22 Wachstumsfördernde peptide für nierenepithelzellen
EP98924865A EP1034187B1 (fr) 1997-11-20 1998-05-22 Proteines et peptides stimulant la croissance des cellules epitheliales renales
JP2000522130A JP3820102B2 (ja) 1997-11-20 1998-05-22 腎臓上皮細胞に対するインビトロおよびインビボでの増殖促進タンパク質およびペプチド
AT98924865T ATE257486T1 (de) 1997-11-20 1998-05-22 Wachstumsfördernde proteine und peptide für epithelzellen von nieren

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US86385397A 1997-05-27 1997-05-27
US08/974,775 1997-11-20
US08/974,775 US6096706A (en) 1997-11-20 1997-11-20 Growth-promoting proteins and peptides for kidney epithelial cells

Publications (1)

Publication Number Publication Date
WO1999026974A1 true WO1999026974A1 (fr) 1999-06-03

Family

ID=27127783

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US1998/010574 WO1999026974A1 (fr) 1997-05-27 1998-05-22 Proteines et peptides stimulant la croissance in vitro et in vivo pour cellules epitheliales renales

Country Status (1)

Country Link
WO (1) WO1999026974A1 (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2005030221A1 (fr) * 2003-09-29 2005-04-07 Meiji Dairies Corporation Agent therapeutique contre la degenerescence maculaire liee a l'age
CN114134191A (zh) * 2020-09-04 2022-03-04 琛蓝(美国)营养制品股份有限公司 一种抗炎护肾的蛤蜊肽的制备方法和应用

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH03128330A (ja) * 1989-05-02 1991-05-31 Takeda Chem Ind Ltd 虚血性腎疾患の予防・治療剤
US5135856A (en) * 1987-06-24 1992-08-04 Arch Development Corp. Production of autocrine growth factors
WO1993007900A1 (fr) * 1991-10-18 1993-04-29 Cantab Pharmaceuticals Research Limited Perfusion in vitro de greffes de reins avec des anticorps
US5476922A (en) * 1987-06-24 1995-12-19 Arch Development Corporation Methods and compositions for the preparation and use of autocrine growth factors
US5618917A (en) * 1995-02-15 1997-04-08 Arch Development Corporation Methods and compositions for detecting and treating kidney diseases associated with adhesion of crystals to kidney cells

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5135856A (en) * 1987-06-24 1992-08-04 Arch Development Corp. Production of autocrine growth factors
US5476922A (en) * 1987-06-24 1995-12-19 Arch Development Corporation Methods and compositions for the preparation and use of autocrine growth factors
JPH03128330A (ja) * 1989-05-02 1991-05-31 Takeda Chem Ind Ltd 虚血性腎疾患の予防・治療剤
WO1993007900A1 (fr) * 1991-10-18 1993-04-29 Cantab Pharmaceuticals Research Limited Perfusion in vitro de greffes de reins avec des anticorps
US5618917A (en) * 1995-02-15 1997-04-08 Arch Development Corporation Methods and compositions for detecting and treating kidney diseases associated with adhesion of crystals to kidney cells

Non-Patent Citations (4)

* Cited by examiner, † Cited by third party
Title
DIJKE TEN P ET AL: "GROWTH FACTORS FOR WOUND HEALING", BIO/TECHNOLOGY, vol. 7, no. 8, 1 August 1989 (1989-08-01), pages 793 - 798, XP000073312 *
HAMMERMANN M.R. ET AL.: "Role of Growth factors in regulation of renal growth", ANU.REV.PHYSIOL., vol. 55, 1993, pages 305-21, XP002085940 *
PATENT ABSTRACTS OF JAPAN vol. 1, no. 1 *
WANG, S. ET AL: "Role of growth factors in acute renal failure", NEPHROL., DIAL., TRANSPLANT. (1997), 12(8), 1560-1563 CODEN: NDTREA;ISSN: 0931-0509, XP002085941 *

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2005030221A1 (fr) * 2003-09-29 2005-04-07 Meiji Dairies Corporation Agent therapeutique contre la degenerescence maculaire liee a l'age
CN114134191A (zh) * 2020-09-04 2022-03-04 琛蓝(美国)营养制品股份有限公司 一种抗炎护肾的蛤蜊肽的制备方法和应用
CN114134191B (zh) * 2020-09-04 2023-12-12 琛蓝(美国)营养制品股份有限公司 一种抗炎护肾的蛤蜊肽的制备方法和应用

Similar Documents

Publication Publication Date Title
JP4344012B2 (ja) 組織形成因子誘導による神経の再生と修復
AU772778B2 (en) Novel inhibitors of angiogenesis and tumor growth
US5436228A (en) Chemotactic wound healing peptides
EP1989228B1 (fr) Fragments de peptides derives de la metallothioneine
US7611865B2 (en) Polynucleotides encoding truncated glial cell line-derived neurotrophic factor
US6262024B1 (en) Neuron regulatory factor for promoting neuron survival
JP4686379B2 (ja) 腎臓上皮細胞に対するインビトロおよびインビボでの増殖促進タンパク質およびペプチド
US7550438B2 (en) Methods for production of growth-promoting proteins and peptides for kidney epithelial cells
AU703297B2 (en) Cervical Ripening
EP2382982A2 (fr) Peptides de régéneration neurale et procédés d'utilisation de ces derniers dans le traitement des lesions cerebrales
JPS6348299A (ja) 新規な軟骨由来の白血球エラスタ−ゼ阻害剤
ES2259458T3 (es) Persefina humana.
WO2001089582A1 (fr) Prophylactiques de l'hypertension pulmonaire et remèdes
FI91484C (fi) Menetelmä uuden solun kasvua säätelevän tekijän, onkostatiini M:n valmistamiseksi
WO1999026974A1 (fr) Proteines et peptides stimulant la croissance in vitro et in vivo pour cellules epitheliales renales
FI81365B (fi) Foerfarande foer framstaellning av biologiskt aktiva polypeptider.
US5262298A (en) Method to assess the ability of a substance to inhibit or stimulate keratinocyte autocrine factor production
JP2000511511A (ja) 腫瘍成長阻害及び毛細管増殖のための生物学的活性タンパク質、コラーゲンフラグメントＨＦ―ＣＯＬＬ―１８／５１４ｃｆ
US6329500B1 (en) Transforming growth factor-β binding site
MXPA00011490A (en) Peptide antiangiogenic drugs

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AL AM AT AU AZ BA BB BG BR BY CA CH CN CU CZ DE DK EE ES FI GB GE GH GM GW HU ID IL IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MD MG MK MN MW MX NO NZ PL PT RO RU SD SE SG SI SK SL TJ TM TR TT UA UG US UZ VN YU ZW

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): GH GM KE LS MW SD SZ UG ZW AM AZ BY KG KZ MD RU TJ TM AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE BF BJ CF CG CI CM GA GN ML MR NE SN TD TG

DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
121 Ep: the epo has been informed by wipo that ep was designated in this application
ENP Entry into the national phase

Ref document number: 2310677

Country of ref document: CA

Ref country code: CA

Ref document number: 2310677

Kind code of ref document: A

Format of ref document f/p: F

NENP Non-entry into the national phase

Ref country code: KR

WWE Wipo information: entry into national phase

Ref document number: 76935/98

Country of ref document: AU

WWE Wipo information: entry into national phase

Ref document number: 1998924865

Country of ref document: EP

WWP Wipo information: published in national office

Ref document number: 1998924865

Country of ref document: EP

REG Reference to national code

Ref country code: DE

Ref legal event code: 8642

WWG Wipo information: grant in national office

Ref document number: 76935/98

Country of ref document: AU

WWG Wipo information: grant in national office

Ref document number: 1998924865

Country of ref document: EP

点击 这是indexloc提供的php浏览器服务，不要输入任何密码和下载