Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P00790 (PGA)
 2,475 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Isolated human glomeruli were digested with purified bacterial collagenase yielding epithelial cells. These cells grew to saturation density and did not become multi-layered. They were identified as visceral glomerular epithelial cells by their morphologic appearance by phase and electron microscopy and by the presence of surface receptors for C3b. Neither Factor VIII antigen nor Fc receptors were observed. The glomerular epithelial cells synthesized a collagenous protein that was antigenically similar to human glomerular basal lamina. Proteins precipitated from visceral epithelial cell medium with affinity purified antibody against noncollagenous glomerular basal lamina antigens yielded a single collagenase labile protein that by sodium dodecyl sulfate/polyacrylamide gel electrophoresis migrated with an apparent Mr of 168,000 in the presence of reducing agents. Analysis of hydroxyproline isomers yielded a ratio of 3-hydroxyproline to total hydroxyproline of 0.17. Pepsin digestion yielded a disulfide-bonded multimer which, with reduction, migrated with an apparent Mr of 148,000. These data demonstrate that human glomerular visceral epithelial cells can be isolated and propagated in vitro and that they synthesize a collagen similar to that found in vivo.
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PMID:Human glomerular visceral epithelial cells synthesize a basal lamina collagen in vitro. 9 Nov 67

In order to maximize staining, modifications of immunostaining methods have included proteolytic enzyme digestion of tissue. The authors performed a study of the effect of ficin in 110 paraffinized specimens, including tonsil, lymph nodes, benign vascular and nerve sheath tumors, and various carcinomas and sarcomas. This agent was compared with pepsin and bromelain, as alternative proteases. A panel of monoclonal and polyclonal antibodies was used, with and without previous digestion by ficin, pepsin, and bromelain. A score was assigned to each stain, based on the number and intensity of reactive cells. Ficin enhanced staining markedly in immunostains with antibodies to keratin and Factor VIII-related antigen (F8RAG). Conversely, it abolished staining for LN-2 (a lymphoid marker) and weakened reactivity for S-100 in nerve sheath tumors. Bromelain produced similar results, except that it enhanced S-100. Pepsin was comparatively less active than ficin and bromelain overall but did produce the greatest amplification of vimentin staining in sarcomas. Digestion with any of the three enzymes failed to influence reactivities of leukocyte common antigen, UCHL-1 (a lymphoid marker), alpha-1-antichymotrypsin, carcinoembryonic antigen, epithelial membrane antigen, and blood group isoantigens. These results may reflect a dissimilar recognition of peptide targets in some antigenic proteins, by ficin, bromelain, and pepsin. Hence, one enzymatic agent is unlikely to produce optimal staining for all determinants. With this proviso, however, ficin appeared to be the best general enhancer for antigens known to require vigorous digestion (e.g., keratin; F8RAG) for optimal reactivity in paraffin sections.
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PMID:The use of proteolysis with ficin, for immunostaining of paraffin sections. A study of lymphoid, mesenchymal, and epithelial determinants in human tissues. 245 44