Increase in tumor necrosis factor-alpha mRNA but not perforin mRNA expression in response to two newly characterized anti-LFA-1 monoclonal antibodies.
We have generated two monoclonal antibodies (mAb), designated anti-1B11 and anti-4F9, directed to the human lymphocyte-function-associated antigen-1 (LFA-1). Indirect immunofluorescence with both mAb showed a bimodal distribution of antigen on the surface of T, natural killer (NK), and lymphokine-activated killer (LAK) cells. Neither mAb reacted with the epitopes recognized by TA1 and Mo-1 mAb on the alpha-chain of the heterodimer. Anti-1B11 and anti-4F9 immunoprecipitated polypeptide chains with molecular weights of 177 and 95 kD. Both mAb inhibited cytolytic T lymphocytes (CTL), NK, and LAK cell-mediated cytotoxicity without affecting antibody-dependent cellular cytotoxicity (ADCC). The proliferative responses of T cells to allogeneic cells were inhibited by anti-1B11 and anti-4F9, whereas the responses to phytohemagglutinin P and concanavalin A were not affected. Anti-1B11 and anti-4F9 blocked effector cell (EC)-target cell (TC) conjugate formation by 50%. Only anti-4F9 cross-reacted with LFA-1 on porcine peripheral blood lymphocytes and inhibited porcine NK, LAK, and ADCC activities. Because LFA-1 also functions at the level of signal transduction during T cell activation and we previously showed that CTL rapidly degraded perforin and tumor necrosis factor-alpha (TNF alpha) mRNA after interaction with sensitive TC, we examined the effects of the mAb on the messages for perforin and TNF alpha. Treatment of CTL with anti-1B11 and anti-4F9 induced TNF alpha message and protein levels of TNF alpha, but did not alter perforin mRNA levels.
Hommel-Berrey
G
G
Department of Medicine, Indiana University School of Medicine, Indianapolis 46202-5128.
Bochan
M
M
Brahmi
Z
Z
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D002460:Cell Line; D003601:Cytotoxicity Tests, Immunologic; D005260:Female; D005455:Fluorescent Antibody Technique; D006801:Humans; D015979:Killer Cells, Lymphokine-Activated / Q000276:immunology; D007694:Killer Cells, Natural / Q000276:immunology; D008213:Lymphocyte Activation / Q000276:immunology; D016169:Lymphocyte Function-Associated Antigen-1 / Q000276:immunology*; D016131:Lymphocyte Subsets / Q000276:immunology*; D008562:Membrane Glycoproteins / Q000096:biosynthesis*; D051379:Mice; D008807:Mice, Inbred BALB C; D054353:Perforin; D052899:Pore Forming Cytotoxic Proteins; D011233:Precipitin Tests; D012333:RNA, Messenger / Q000096:biosynthesis*; D013552:Swine; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis*
D000911:Antibodies, Monoclonal; D016169:Lymphocyte Function-Associated Antigen-1; D008562:Membrane Glycoproteins; D052899:Pore Forming Cytotoxic Proteins; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; D054353:Perforin