CD11a-c/CD18 and GP84 (LB-2) adhesion molecules on human large granular lymphocytes and their participation in natural killing.
Effect of mAb against the CD11a-c, CD18, and GP84 adhesion molecules on the binding and cytotoxicity of human NK cells was studied. The target cells were K562, MOLT-4, Raji, and fresh uncultured autologous endometrial carcinoma cells. Antibodies against adhesion relevant epitopes of CD11a(TA-1/LFA-1), CD11b(Mol/OKM1/Mac1), or CD11c (Leu-M5) did not inhibit NK function. The mAb 60.3 against CD18, the common beta-chain associated to CD11a-c, strongly inhibited both the binding and cytotoxicity of large granular lymphocytes (LGL) against all the target cells tested. Also the antibody LB-2 against the GP84 adhesion molecule inhibited NK function to some degree. 60.3 and LB-2 antibodies exerted an additive effect in the inhibition of both binding and cytotoxicity. However, even this antibody combination did not completely block NK activity, suggesting a heterogeneity of adhesion structures in the NK system. According to both FACS analyses and immunoprecipitation studies, all the tested antibodies recognized either a subpopulation or all of LGL. On the other hand, antibodies against CD11b, CD11c, and LB-2 showed only marginal reactivity with highly purified LGL-free T cells.
D000911:Antibodies, Monoclonal / Q000502:physiology; D000943:Antigens, Differentiation / Q000276:immunology / Q000302:isolation & purification*; D000954:Antigens, Surface / Q000276:immunology / Q000302:isolation & purification*; D001666:Binding Sites, Antibody; D018845:CD11 Antigens; D018821:CD18 Antigens; D015815:Cell Adhesion Molecules; D002469:Cell Separation; D003602:Cytotoxicity, Immunologic; D006801:Humans; D007113:Immunity, Innate; D007694:Killer Cells, Natural / Q000032:analysis / Q000276:immunology*; D008562:Membrane Glycoproteins / Q000276:immunology / Q000302:isolation & purification*
D000911:Antibodies, Monoclonal; D000943:Antigens, Differentiation; D000954:Antigens, Surface; D018845:CD11 Antigens; D018821:CD18 Antigens; D015815:Cell Adhesion Molecules; D008562:Membrane Glycoproteins