T cell line-mediated EAE: prevention and therapy by a monoclonal antibody specific for T lymphoblasts.

We studied the effect of a novel monoclonal antibody, pta-3, on T cell line-mediated experimental allergic encephalomyelitis (EAE). The antibody is specific for a differentiation antigen expressed by activated rat T lymphocytes and is cytotoxic in the presence of rat complement for a minor subpopulation of leukocytes, including encephalitogenic T cells (Schluesener et al. 1986). Single intraperitoneal injections of antibody effectively prevented or abrogated lethal EAE. Therapeutic effect was dependent on time of treatment, but even established disease could be cured. Due to the specificity of the antibody for the disease inducing lymphocytes, no side effects of treatment could be observed in living animals or by autopsy.