Functional evidence that intercellular adhesion molecule‐1 (icam‐1) is a ligand for lfa‐1d‐ependent adhesion in t cell‐mediated cytotoxicity

摘要

AbstractAlthough intercellular adhesion molecule‐1 (ICAM‐1) has been implicated as a ligand in some LFA‐1‐dependent adhesion, its importance to T cell function has not been established. The present studies investigate the importance of ICAM‐1 for human cytotoxic T lymphocytes (CTL), both in their formation of antigen‐independent conjugates (AIC) and in their lysis of targets. Analysis of monoclonal antibody (mAb) inhibition of AIC formation indicate that ICAM‐1 mAb 1 blocks (a) AIC formation with some but not all targets; (b)the LFA‐1 pathway but not the CD2LFA‐3 pathway of adhesion; (c) by binding to the target cell, not the T cell. In studies of cell‐mediated lysis (CML) ICAM‐1 mAb inhibited lysis of some targets, such as U‐937, that use ICAM‐1 predominantly in AIC formation; CML on some other targets is not inhibited by ICAM‐1 mAb. These data indicate that ICAM‐1 is a ligand for AIC formation, antigen‐specific CTL recognition and cytolysis of particular target cells. The data also indicate that ICAM‐1 is not used in LFA‐1‐dependent CTL interactions with all kinds of target cells, suggesting the exist