Anti-Fas antibody induces apoptosis in cultured human renal interstitial fibroblasts.
OBJECTIVE
To detect if Fas is expressed in human renal interstitial fibroblasts (hRIFs) and apoptosis of hRIFs can be induced by specific anti-Fas antibody.


METHODS
hRIFs were cultured from isolated papillae of human kidney, and identified by morphologic examination, assay of antigenic components and culture in D-valine selective medium. Fas expression in normal hRIFs was detected by RT-PCR and immunocytochemistry staining. After hRIFs were incubated with interferon gamma (gamma-IFN 500 U/ml, 1000 U/ml, 1500 U/ml and 2000 U/ml, respectively) for 48 hours, Fas expression was determined by Northern blot, Western blot and flow cytometry. hRIFs pre-stimulated with gamma-IFN (500 U/ml, 48 hours) were incubated with anti-Fas antibody (IgM, 0.5 microgram/ml) for 12 hours. And apoptosis was identified by morphologic examination, DNA ladder assay and flow cytometry.


RESULTS
The cultured hRIFs showed a shuttle-like shape and were positively stained by labeled anti-vimentin antibody but negatively stained by anti-epithelial membrane antibody. They could not grow in the D-valine selective medium and died partly in a week. Fas mRNA and protein were expressed in normal hRIFs and markedly upregulated by stimulation with gamma-IFN. Apoptosis in gamma-IFN pre-stimulated hRIFs was induced by anti-Fas antibody, showing cell nuclear shrinkage and condensation in morphologic feature, internucleosomal DNA fragmentation in DNA ladder assay and a pick of hypo-diploid nuclei by flow cytometry.


CONCLUSIONS
Fas is normally expressed in hRIFs and can be markedly upregulated by gamma-IFN. Anti-Fas antibodies can induce apoptosis of hRIFs pre-stimulated with gamma-IFN.
Cheng
L
L
Division of Nephrology, the First Hospital, Beijing Medical University, Beijing 100034, China.
Chen
Y
Y
D000911:Antibodies, Monoclonal / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D005347:Fibroblasts / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D007371:Interferon-gamma / Q000494:pharmacology; D007668:Kidney / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D012333:RNA, Messenger / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D019014:fas Receptor / Q000235:genetics / Q000276:immunology*
D000911:Antibodies, Monoclonal; D012333:RNA, Messenger; D019014:fas Receptor; D007371:Interferon-gamma