Protection of human amniotic epithelial cells (HAEC) from complement-mediated lysis: expression on the cells of three complement inhibitory membrane proteins.
Cultured human amniotic epithelial cells (HAEC) were found by immunofluorescence microscopy to express three complement inhibitory membrane proteins, CD59 antigen, decay-accelerating factor (DAF) and membrane attack complex (MAC) inhibitory protein (MIP), on their surfaces. The effects of incubation with Fab2 fragments of monoclonal antibodies (mAb) raised against these proteins on susceptibility of sensitized cells to lysis by homologous complement was examined. Percentage cell lysis was markedly increased in the presence of Fab2 anti-CD59 and to a lesser, but significant, extent in the presence of Fab2 anti-DAF. Fab2 anti-MIP did not alter the sensitivity of the cells to lysis by complement.
Department of Medical Biochemistry, UWCM, Heath Park, Cardiff, U.K.
I A
IA
Rooney
B P
BP
Morgan
D000650:Amnion / Q000276:immunology*; D000943:Antigens, Differentiation / Q000032:analysis; D018958:CD55 Antigens; D018957:CD59 Antigens; D002478:Cells, Cultured; D003169:Complement Inactivator Proteins / Q000032:analysis*; D015938:Complement Membrane Attack Complex / Q000037:antagonists & inhibitors; D003165:Complement System Proteins / Q000276:immunology*; D003602:Cytotoxicity, Immunologic; D004848:Epithelium / Q000276:immunology; D006801:Humans; D008562:Membrane Glycoproteins / Q000032:analysis; D008565:Membrane Proteins / Q000032:analysis*
D000943:Antigens, Differentiation; D018958:CD55 Antigens; D018957:CD59 Antigens; D003169:Complement Inactivator Proteins; D015938:Complement Membrane Attack Complex; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D003165:Complement System Proteins