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W F Doe

Publications and source records attributed to W F Doe.

At least 37 records · Page 2Linked to original sources
PubMed1998

Antibiotic-associated haemorrhagic colitis.

Antibiotic-associated haemorrhagic colitis is an uncommon cause of bloody diarrhoea in patients taking penicillin or penicillin-related antibiotics. Symptoms of abdominal pain and bloody diarrhoea occur within 1 week of antibiotic use and resolve without specific therapy within days of discontinuing the offending antibiotic. There is an apparent increased incidence of the disease in patients of Oriental ethnicity. The pathogenesis is unknown. We present two cases of haemorrhagic colitis in patients taking penicillin-related antibiotics who presented within 4 months of each other. One of the patients was being treated for Helicobacter pylori infection. The published literature is reviewed with particular emphasis on the histology and pathogenesis of the condition.

Adult↗
PubMed1998

Urokinase type plasminogen activator receptor expression in colorectal neoplasms.

BACKGROUND: The urokinase type plasminogen activator receptor (uPAR) may play a critical role in cancer invasion and metastasis. AIMS: To study the involvement of uPAR in colorectal carcinogenesis. METHODS: The cellular expression and localisation of uPAR were investigated in colorectal adenomas and invasive carcinomas by in situ hybridisation, immunohistochemistry, and northern and western blot analyses. RESULTS: uPAR mRNA expression was found mainly in the cytoplasm of dysplastic epithelial cells of 30% of adenomas with mild (19%), moderate (21%), and severe (47%) dysplasia, and in that of carcinomatous cells of 85% of invasive carcinomas: Dukes' stages A (72%), B (93%), and C (91%). Some stromal cells in the adjacent neoplastic epithelium were faintly positive. Immunoreactivity for uPAR was detected in dysplastic epithelial cells of 14% of adenomas and in carcinomatous cells of 49% of invasive carcinomas. uPAR mRNA and protein concentrations were significantly higher in severe than in mild or moderate dysplasia (p<0.05); they were notably higher in Dukes' stage A than in severe dysplasia (p<0.05), and significantly higher in Dukes' stage B than in stage A (p<0.05), but those in stage B were not different from those in stage C or in metastatic colorectal carcinomas of the liver. CONCLUSIONS: Colorectal adenoma uPAR, expressed essentially in dysplastic epithelial cells, was upregulated with increasing severity of atypia, and increased notably during the critical transition from severe dysplasic adenoma to invasive carcinoma. These findings implicate uPAR expression in the invasive and metastatic processes of colorectal cancer.

Blotting, Northern↗
PubMed1997

Expression of urokinase-type plasminogen activator receptor in hepatocellular carcinoma.

It is well known that a urokinase-type plasminogen activator receptor (uPAR) is a key protein in the plasminogen activation system, which plays a proteolytically important role in the invasion and metastasis of various cancer cells. To assess the expression of uPAR in hepatocellular carcinoma (HCC), we analyzed the expression of uPAR messenger RNA (mRNA) and the protein in 31 pair-samples of solitary HCC and nontumorous liver tissues from the same patients. Fifteen samples exhibited no histological potential of recurrence, such as portal involvement or intrahepatic metastasis (group A), and 16 samples exhibited such histological features (group B). Seventy-one percent of the cases showed uPAR signals, and these signals were mainly localized at the cytoplasm of the tumor cells and tended to be at the front of invasive foci. 87.5% of the cases in group B showed uPAR signals against 53.3% of the cases in group A (P < .05). The rate of recurrence in the uPAR positive/negative cases in group A was 75.0% and 14.3%, respectively (P < .05). In non-neoplastic cases, e.g., chronic active hepatitis and cirrhosis, weak uPAR mRNA and protein signals were detected in hepatocytes neighboring the portal tracts, suggesting that this protein plays some role in such cases. The present study indicates that uPAR plays an important role at least in its initial stage in invasion and metastasis of HCC, and that uPAR expression can be a candidate predictor of these factors.

Antigens, Neoplasm↗
PubMed1996

Evidence of oxidant-induced injury to epithelial cells during inflammatory bowel disease.

Evidence of in vivo oxidant-induced injury in inflammatory bowel disease (IBD) is largely indirect. Colon epithelial crypt cells (CEC) from paired specimens of histologically normal and inflamed bowel from IBD patients with active disease were examined for altered protein thiol redox status as an indicator of oxidative damage. When CEC preparations from 22 IBD patients were labeled with the reduced-thiol-specific probe [14C]-iodoacetamide (IAM), there was decreased labeling of a number of proteins indicating oxidation of thiol groups in CEC from inflamed mucosa compared to paired normal mucosa, especially the loss of thiol labeling of a 37-kD protein which was almost completely lost. The loss of reduced protein thiol status for the 37-kD band was paralleled by loss of epithelial cell glyceraldehyde-3-phosphate dehydrogenase (GAPDH, EC 1.2.1.12) enzyme activity, an enzyme known to contain an essential reduced cysteine (Cys149) at the active site. The identity of the 37-kD protein as GADPH monomer was confirmed by NH2-terminal amino acid sequence analysis. To examine whether this type of in vivo injury could be attributed to biologically relevant oxidants produced by inflammatory cells, CEC prepared from normal mucosa were exposed to H2O2, OCl-, nitric oxide (NO), and a model chloramine molecule chloramine T (ChT) in vitro. Dose-dependent loss of IAM labeling and GAPDH enzyme activity was observed. The efficacy (IC50) against IAM labeling was OCl- >> ChT > H2O2 > NO (52 +/- 3, 250 +/- 17, 420 +/- 12, 779 +/- 120 microM oxidant) and OCl- >> ChT > NO > H2O2 (89 +/- 17, 256 +/- 11, 407 +/- 105, 457 +/- 75 microM oxidant), respectively, for GAPDH enzyme activity. This study provides direct evidence of in vivo oxidant injury in CEC from inflamed mucosa of IBD patients. Oxidation and inhibition of essential protein function by inflammatory cells is a potential mechanism of tissue injury that may contribute to the pathogenesis of the disease and supports the exploration of compounds with antioxidant activity as new therapies for IBD.

Amino Acid Sequence↗
PubMed1996

Enhanced expression and production of monocyte chemoattractant protein-1 in inflammatory bowel disease mucosa.

Peripheral blood monocytes are recruited to the inflamed mucosa of inflammatory bowel disease but the specific chemotactic signals responsible for their attraction are not known. Monocyte chemoattractant protein-1 (MCP-1) is a chemokine with potent monocyte attracting and activating properties and the aim of this study was to examine its expression and production in inflammatory bowel disease. In situ hybridization demonstrated mRNA for MCP-1 in macrophages, some of which had been recently recruited from the circulation as demonstrated by their co-expression of the monocyte marker CD 14, as well as in smooth muscle and endothelial cells in inflamed mucosa. Immunohistochemical studies showed a corresponding distribution of MCP-1 protein production by macrophages, smooth muscle, and endothelial cells. By contrast minimal MCP-1 mRNA expression and protein were found in histologically normal mucosa. Macrophages isolated from surgically resected inflammatory bowel disease colons and examined by Northern analysis expressed MCP-1 mRNA significantly more frequently (15/24 vs. 0/19, P< 0.0001) than macrophages from histologically normal mucosa from colon cancer resections. Blood monocytes stimulated by lipopolysaccharide and treated with hydrocortisone, 5-aminosalicylic acid, or cyclosporin A showed reduced MCP-1 expression and production in the presence of these agents. This study demonstrates increased expression of MCP-1 mRNA and protein and cells of origin of MCP-1 in inflamed intestinal mucosa. Together with the demonstrated influence of therapeutic agents on monocyte MCP-1 production the findings suggest a role for MCP-1 in monocyte attraction to the mucosal lesion of inflammatory bowel disease.

Adolescent↗
PubMed1996

A highly polymorphic CA/GT repeat in intron 3 of the human urokinase receptor gene (PLAUR).

We describe the first highly polymorphic microsatellite marker for the human urokinase plasminogen activator receptor gene (PLAUR). The urokinase receptor (uPAR) has a central role in cancer invasion and metastasis, which may enable the development of new anti-metastatic therapies. Analysis of the marker genotypes in colorectal cancer cell lines revealed three alleles that were not detected in a series of healthy control individuals, which encourages further genetic study of the role of uPAR in cancer.

Alleles↗
PubMed1996

Interleukin 8: cells of origin in inflammatory bowel disease.

Neutrophils are important cellular mediators in inflammatory bowel disease (IBD). Interleukin (IL)8, a powerful neutrophil chemoattractant, is found in increased quantities in inflamed mucosa, but the cells of origin are uncertain. IL8 gene expression was studied by in situ hybridisation in uninflamed intestinal tissue resected for colon carcinoma (n = 7) and in inflamed colonic tissue resected for IBD (n = 11). Immunohistochemistry was used to assess the phenotype of IL8 expressing macrophages and the production of IL8 protein. Macrophages isolated from intestinal resections and lipopolysaccharide stimulated peripheral blood monocytes treated with 5-aminosalicylic acid, hydrocortisone, and cyclosporin A were examined for IL8 mRNA by northern blotting and IL8 secretion by enzyme linked immunosorbent assay (ELISA). In all cases IL8 mRNA was detected by in situ hybridisation in macrophages and neutrophils adjacent to ulceration in inflamed bowel, but not detected in uninflamed mucosa from carcinoma resections. Recently recruited CD14 positive macrophages were responsible for some of this IL8 expression. IL8 protein was present in the same distribution as mRNA. Epithelial cells in normal and inflamed tissue showed neither mRNA nor protein. IL8 mRNA was expressed significantly more commonly by macrophages from IBD affected than from normal mucosa, and IL8 secretion by IBD but not normal colon macrophages was augmented significantly by lipopolysaccharide treatment. IL8 expression and production by lipopolysaccharide treated blood monocytes was inhibited by the therapeutic agents tested. These results show that neutrophils and recently recruited macrophages are responsible for production of IL8 in IBD, suggesting a mechanism for a continuing cycle of neutrophil attraction. Agents used therapeutically in these diseases may be effective in part by disrupting this cycle.

Adolescent↗
PubMed1996

RNA-based mutation screening in hereditary nonpolyposis colorectal cancer.

Hereditary nonpolyposis colorectal cancer (HNPCC) is a cancer syndrome inherited in an autosomal dominant fashion. Four susceptibility genes are known, which code for DNA mismatch repair enzymes. The purpose of this study was to identify the HNPCC gene defects in a cohort of Australian HNPCC families and to evaluate the use of RNA-based screening methods. Six mutations were identified, four in the hMLH1 gene and two in hMSH2, by using a combination of DNA-based and RNA-based methods. One of the hMLH1 defects was a missense mutation, and the other five mutations would be expected to result in a shortened protein. These included a rare type of mRNA splicing mutation in hMLH1 exon 17. By use of reverse-transcriptase (RT) PCR, defective transcripts were detectable for three of the hMLH1 mutations but not for the fourth one, which was predicted to cause skipping of exon 15. Furthermore, many more alternative transcripts for the hMLH1 gene were found than previously described, and these were more abundant in the RNA samples prepared from whole blood than from lymphoblastoid cell lines. This confounded RNA-based screening for HNPCC mutations, because it was difficult to determine which aberrant RT-PCR fragment was the real hereditary defect. One of the splice-site mutations reported here causes skipping of exons 9 and 10, which also occurs as an alternative transcript. When the protein-truncation test was used, the results were indistinguishable between the patients in this family and controls. Other aberrant transcripts were also observed that varied in size between individuals but were unrelated to the hereditary defects. This study has important implications for the design of reliable diagnostic tests for HNPCC gene defects.

Cell Line↗
PubMed1995

Sodium butyrate inhibits expression of urokinase and its receptor mRNAs at both transcription and post-transcription levels in colon cancer cells.

The effects of butyrate on the modulation of urokinase plasminogen activator (uPA) and its receptor (uPAR) mRNAs were studied. While both mRNA levels were increased after stimulation by tumor necrosis factor alpha (TNF alpha), phorbol ester (PMA) and cycloheximide, they were inhibited by butyrate at 2.5 to 25 mM. Nuclear run-on transcription assays indicated that uPA mRNA was modulated by butyrate at the transcriptional level but the uPAR gene was regulated at both transcriptional and post-transcriptional levels in the presence or absence of TNF alpha. In the presence of PMA, however, butyrate acts at the post-transcriptional level on both genes.

Butyrates↗
PubMed1995

Structure of the human urokinase receptor gene and its similarity to CD59 and the Ly-6 family.

Urokinase plasminogen activator receptor (uPAR) gene expression has been implicated in many important biological processes including cell invasiveness and migration. The uPAR gene was cloned from a human genomic library by hybridization with a uPAR cDNA. The complete structure of the human uPAR gene, including a 21.23-kb transcription unit with 204 bp 5' and 239 bp 3' flanking sequences, was determined by comparison with the uPAR cDNA sequence. The uPAR gene is composed of seven exons and six introns. The seven exons of 101, 111, 144, 162, 135, 147 and 563 bp are separated by six introns of approximately 2.04, 2.62, 8.42, 0.906, 3.10 and 2.78 kb. Exons 1-7 encode 19, 37, 48, 54, 45, 49 and 83 amino acid residues, respectively. A CpG-rich island and sequences related to the transcription factors AP-1, AP-2, c-Jun and NF kappa B are present, but no potential TATA or CAAT boxes were found in the proximal 5' region of the uPAR gene. Comparison of the exon organization of the uPAR gene with that of human CD59 and murine Ly-6 reveals similarity to all three domains encoded by the uPAR exons (2 + 3), (4 + 5) and (6 + 7). These data enable elucidation of the mechanisms involved in regulation of the uPAR gene expression and provide further evidence that the uPAR gene belongs to the Ly-6 superfamily.

Amino Acid Sequence↗
PubMed1995

Amiloride modulates urokinase gene expression at both transcription and post-transcription levels in human colon cancer cells.

Activity of receptor-bound urokinase plasminogen activator (uPA) on the surface of colon cancer cells appears to be a function of the number of uPA receptors. The regulation of uPA therefore may determine the invasive phenotype. The effects of amiloride on the modulation of uPA mRNA and protein induced by phorbol ester (PMA) and cycloheximide (CHX) were studied in four colon cancer cell lines, HCT116, KM12SM, LIM1215 and LS123. Northern blot analyses showed that PMA induced uPA mRNA that peaked at 2-48 h in HCT116 cells. In all colon cancer cell lines tested, the expression of uPA mRNA by PMA was super-induced after the addition of the protein synthesis inhibitor CHX, suggesting that stimulation of uPA gene expression does not require de novo protein synthesis. uPA mRNA was also induced by CHX alone, indicating that there may be a labile protein which inhibits uPA mRNA processing. Amiloride profoundly inhibited uPA mRNA production at concentrations between 0.1-1 mM in the presence or absence of PMA or CHX. uPA protein levels on the colon cancer cell surface reflected PMA induction and amiloride inhibition of uPA mRNA levels. Transcriptional elongation experiments using isolated nuclei indicated that while the induction effects of PMA or CHX on uPA gene expression were mediated at the post-transcriptional level, amiloride acted at both transcription and post-transcription levels. The inhibitory effects of amiloride on uPA gene expression reported in this paper may offer the prospect of developing new therapeutic approaches to the prevention of invasion and metastasis by adenocarcinomas.

Amiloride↗
PubMed1995

Depleted mucosal antioxidant defences in inflammatory bowel disease.

Experimental approaches designed to define the role of reactive oxygen and nitrogen species generated by inflammatory cells in the tissue injury seen in inflammatory bowel disease rarely consider the chemical antioxidant defences against such increased oxidant stress in the mucosa. In this investigation, we have analysed components of the aqueous and lipid phase antioxidant mucosal defences by measuring the total peroxyl radical scavenging capacity and the levels of urate, glutathione, alpha-tocopherol, and ubiquinol-10 in paired noninflamed and inflamed mucosal biopsies from inflammatory bowel disease patients. Compared to paired noninflamed mucosa, decreases were observed in inflamed mucosa for total peroxyl radical scavenging capacity (55%, p = 0.0031), urate [Crohn's disease (CD), 62.2%, p = 0.066; ulcerative colitis (UC), 47.3%, p = 0.031], glutathione (UC, 59%, 7/8 patients, ns), total glutathione (UC 65.2%, 6/8 patients, ns), ubiquinol-10 (CD, 75.7%, p = 0.03; UC, 90.5%, p = 0.005). The mean alpha-tocopherol content was unchanged. These observations support our earlier findings of decreased reduced and total ascorbic acid in inflamed IBD mucosa and demonstrate that the loss of chemical antioxidant defences affects almost all the major components. The decreased antioxidant defences may severely compromise the inflamed mucosa, rendering it more susceptible to oxidative tissue damage, hindering recovery of the mucosa and return of epithelial cell layer integrity. The loss of chemical antioxidant components provides a strong rational for developing novel antioxidant therapies for the treatment of inflammatory bowel disease.

Antioxidants↗
PubMed1995

Evidence for a CD14+ population of monocytes in inflammatory bowel disease mucosa--implications for pathogenesis.

Lipopolysaccharide (LPS) is abundant in the intestinal lumen. CD14 is the receptor for the LPS-LPS binding protein complex, and its presence on mononuclear phagocytes allows cell activation by pg/ml concentrations of LPS. We have shown that the recently recruited blood monocyte in inflammatory bowel disease mucosa is CD14+. This study examined the expression of CD14 on macrophages in inflamed (n = 13) and uninflamed (n = 7) intestine by immunohistochemistry, and on disaggregated lamina propria mononuclear cells (12 from inflamed, 17 from uninflamed intestine) and peripheral blood mononuclear cells (n = 26) by flow cytometry, using a panel of three MoAbs directed against CD14. Immunohistochemistry revealed that 3.7% of macrophages in uninflamed intestine were CD14+, while 25.1% of macrophages in active inflammatory bowel disease expressed CD14 (P < 0.02). Flow cytometry demonstrated that CD14 expression by macrophages from Crohn's disease and ulcerative colitis was augmented significantly (P = 0.02 and P = 0.01, respectively) compared with uninflamed intestine, with a discrete population of macrophages in inflammatory bowel disease, not present in normal intestine, which strongly expressed CD14. The characteristically high levels of CD14 on blood monocytes were unaffected by the presence of intestinal inflammation. Given the exposure of lamina propria cells to LPS present in the lumen of the terminal ileum and colon, the increased numbers of CD14+ macrophages in inflammatory bowel disease may result in greatly increased production of inflammatory mediators, thereby suggesting a mechanism for the perpetuation of mucosal inflammation.

Antigens, CD↗
PubMed1995

Altered ascorbic acid status in the mucosa from inflammatory bowel disease patients.

Attempts to establish the presence of oxidant stress and tissue damage in inflammatory bowel disease (IBD) have relied on determining the capacity of peripheral blood inflammatory cells to produce reactive oxygen species (ROS) and other indirect indices. These approaches have failed to address whether or not there are adequate chemical antioxidant defences to prevent oxidative injury in the inflamed mucosa. In this investigation we have determined the mucosal concentrations of reduced and total ascorbic acid and the redox status in paired non-inflamed and inflamed mucosa using colonic biopsies from IBD patients. In inflamed mucosa from Crohn's disease (CD) patients, reduced and total ascorbic acid content decreased by 35% (p = 0.014 and p = 0.009, respectively). In ulcerative colitis (UC) patients, mucosal total ascorbic acid content decreased by 73% (p = 0.069) and reduced ascorbic acid by 41% (p = 0.014). The proportion of total ascorbic acid present in its reduced form in histologically normal mucosa from CD patients was unusually low at approximately 30%. In the paired-inflamed mucosa from CD patients, the redox ratio was also approximately 30% despite the loss of 35% of total ascorbate. In UC patients, the ascorbate redox ratio in the non-inflamed mucosa was 23% which increased to 51% in paired inflamed mucosa. This increase reflected the loss (73%) of total ascorbate. Reduction of dehydroascorbic acid by GSH/NADPH dependent dehydroascorbic acid reductase decreased significantly (p = 0.046) in inflamed mucosa from UC patients, suggesting that the capacity of the inflamed mucosa to maintain the concentration of reduced ascorbic acid is also diminished. HPLC analysis of mucosal preparations for diketogulonic acid, the decomposition product of dehydroascorbic acid, did not account for the loss of total ascorbate in the inflamed mucosa suggesting that ascorbate equivalents underwent further decomposition reactions or were excreted to the colonic lumen. We conclude that the normal luminal environment is strongly oxidising in character and that oxidant stress derived from inflammatory cells contributes to the loss of 35-73% total and reduced ascorbate. In absolute terms, the overall loss of this antioxidant buffering capacity would decrease the capacity of the inflamed mucosa to prevent oxidative tissue damage and hinder recovery of the inflamed mucosa.

2,3-Diketogulonic Acid↗
PubMed1994

Human urokinase receptor expression is inhibited by amiloride and induced by tumor necrosis factor and phorbol ester in colon cancer cells.

The modulation of urokinase plasminogen activator receptor (uPAR) gene expression by tumor necrosis factor alpha (TNF alpha), phorbol ester (PMA) and amiloride was studied in three colon cancer cell lines. uPAR mRNA and protein were induced by TNF alpha and by PMA but were inhibited by amiloride at concentrations of 0.1 to 1 mM in the presence or absence of TNF alpha and PMA. Nuclear run-on transcription assay indicated that the effects of amiloride and TNF alpha were mediated at least in part at the transcriptional level, whereas PMA may act in part via a posttranscriptional mechanism. These results suggested that uPAR gene expression is modulated by multiple signal transduction pathways.

Amiloride↗
PubMed1993

Dendritic cells, the major antigen-presenting cells of the human colonic lamina propria.

Induction of T-cell responses requires the recognition of antigen in association with class II major histocompatibility complex (MHC) antigens on specialized antigen-presenting cells. It was previously demonstrated that dendritic cells were the major antigen-presenting cell in the mouse intestinal lamina propria whilst macrophages were shown to be suppressive. The aim of this study was to compare the antigen-presenting cell activity of human colonic dendritic cells with macrophages. Colonic mucosa was removed from 46 specimens resected for cancer and other non-malignant conditions and lamina propria cell suspensions obtained by EDTA treatment followed by enzymatic digestion. Lamina propria cell suspensions, depleted of macrophages by adherence to insolubilized human immunoglobulin and carbonyl iron phagocytosis, were enriched for dendritic cells by density gradient centrifugation. Yields represented 0.9% (range 0.7-1.4%) of the starting cell number and the degree of enrichment was 30-50%. Immunocytochemistry demonstrated high levels of class II MHC antigen expression, but low levels or absent expression of macrophage and other markers. The ultrastructural features of the low-density cell fraction were typical of dendritic cells with cytoplasmic extensions or veils and the absence of phagocytic vesicles. Populations of cells enriched for macrophages were obtained by harvesting the human immunoglobulin-adherent cells. These cells were > 70% positive for macrophage markers using immunocytochemistry. The ability of lamina propria cells to induce primary T-cell activation was assayed using allogeneic peripheral blood T cells as responders in the mixed leucocyte reaction (MLR). When antigen-presenting activity was assessed using the MLR, the stimulatory activity was present in the dendritic cell-enriched fraction, with little activity present in the macrophage fraction. These data indicate that dendritic cells, not macrophages, are the major cell population capable of generating a mixed leucocyte reaction in the human colonic lamina propria.

Cell Adhesion↗
PubMed1992

Occupancy of the cancer cell urokinase receptor (uPAR): effects of acid elution and exogenous uPA on cell surface urokinase (uPA).

The development of a simple, sensitive fluorimetric assay for the measurement of cell surface-associated urokinase plasminogen activator (uPA) on viable, adherent HCT116 cells in microtitre plates, after a preincubation with purified human plasminogen is described. The assay determines plasmin activity by the cleavage of H-D-Val-Leu-Lys 4-aminomethyl coumarin under near physiological pH and ionic conditions with a sensitivity in the range of 5-100 mIU uPA/well at excitation 355 nm and emission 460 nm. Plasmin generated during the assay converted all cell-surface sc-uPA to tc-uPA, allowing the determination of total uPA activity. Inhibitor studies (PAI-2, amiloride or Glu-Gly-Arg chloromethylketone) confirmed the specificity of the uPA assay. Removal of these agents prior to assay allowed determination of the cell surface sc-uPA:tc-uPA ratio. Cell surface activity was only partially removed by acid elution. This corresponded with the loss of a number of proteins and uPA-containing species as detected by SDS-PAGE, gelatin enzymography and Western blotting. Although the major protein species eluted had a M(r) of 55 kDa, reacted with a commercial anti-human uPA mAb and correlated with the main lytic zone, other higher M(r) species were also eluted from HCT116 cells. Exogenous uPA increased cell-surface activity markedly on cells previously treated with acid. Following acid elution, cell surface uPA activity was restored after 30h in culture suggesting either de novo synthesis or release of pre-formed uPA with subsequent secretion and binding to uPAR. The assay has enabled studies on adherent cells to address questions about the regulation and expression of cell-surface uPA.

Aprotinin↗