Augmentation of adoptively transferred experimental allergic encephalomyelitis by administration of a monoclonal antibody specific for LFA-1 alpha.

We investigated the effect of an anti-leukocyte function antigen 1 (LFA-1 alpha) monoclonal antibody, M17/4.2, on murine relapsing experimental allergic encephalomyelitis (EAE). In vitro investigations demonstrated that M17/4.2 inhibited proliferation with concanavalin A or myelin basic protein. Control mice treated with phosphate buffered saline (PBS) developed a mild to moderate disease at 7-10 days followed by a long-term relapsing clinical course. With administration of M17/4.2, the time of disease onset was unchanged; however, the severity of the disease was greatly augmented, resulting in early mortality. The pathology correlated well with the clinical course. M17/4.2 mice showed more inflammation and demyelination than PBS or anti-CD4 treated mice. Therefore, this anti-LFA-1 specific monoclonal antibody augmented EAE.