Autoimmune effector cells. Part 10: Effector cells of autoimmune encephalomyelitis in healthy nonimmune rats.

This paper describes our ongoing investigation of the activation of effector cells of experimental allergic encephalomyelitis (EAE) from nonimmune Lewis rats by sequential culture of spleen cells (SpC) with myelin basic protein (BP) and transfer to syngeneic recipients. We show that SpC initiate the effector cell activation process, whereas thymocytes (Thy) are ineffective. Intermediary recipients of BP-cultured SpC are 'primed' for EAE, but do not develop the disease; this primed state persists for at least 2 months. No evidence was found that suppressor cells account for the failure of the intermediary recipients to develop EAE. The activation process can be inhibited by including monoclonal anti-Ia antibody in the primary culture, indicating that multiple triggering signals are involved in the activation of autoreactive T cells.