Fig. 1. Inhibition of myosin activation and its effects on LFA-1-mediated T cell attachment to ICAM-1. (A) Attachment of T cells to ICAM-1 with and without Mg²⁺/EGTA stimulation compared with attachment in the presence of Mg²⁺/EGTA plus BDM (myosin ATPase inhibitor, 20 mM, n=6, P=0.02). (B) The effect on T cell attachment to ICAM-1 of MLCK inhibitor ML-7 and ROCK inhibitor Y-27632 (0-50 µM). (C) The effect of various peptides on T cell attachment. Antennapedia linked to a 13-mer peptide containing the auto-inhibitory site of MLCK (ant-MLCK-pep), and, as controls, a scrambled version of the same peptide (ant-scram-pep) and antennapedia only (ant-pep) (representative of 5 experiments). Values are expressed in A and B as the mean±s.e.m. and in C as the mean±s.d.