THE ROLE OF CD44, CD45, CD45RO, CD46 AND CD55 AS POTENTIAL ANTIADHESION MOLECULES INVOLVED IN THE BINDING OF HUMAN TONSILLAR T-CELLS TO PHORBOL 12-MYRISTATE 13-ACETATE-DIFFERENTIATED U-937 CELLS

In this study, we have shown that human tonsillar T cells adhere to phorbol 12‐myristate 13‐acetate(PMA)‐differentiated U‐937 cells. To examine the molecular mechanisms involved, the effect of a panel of monoclonal antibodies upon this adhesion was assessed in a quantitative binding assay. Antibodies against LFA‐1 and ICAM‐1 inhibited binding, directly implicated these molecules in T cell‐PMA‐induced U‐937 adhesion. Furthermore, the adhesion was magnesium but not calcium dependent. Of the remaining antibodies that were tested, none of those against CD2, LFA‐3, Mac‐1, p150,95, CD43, CD45RA or CD56 affected binding. However, antibodies against CD44, CD45, CD45RO, CD46 and CD55 enhanced binding suggesting an anti‐adhesive role for these molecules during U‐937‐T cell interaction. Copyright © 1990 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim