Experimental allergic encephalomyelitis in Lewis rats bearing avian sarcoma virus-induced brain tumors.

Lewis rats bearing avian sarcoma virus (ASV)-induced brain tumors were injected with guinea pig spinal cord emulsion and complete Freund's Adjuvant to determine if they remained susceptible to induction of experimental allergic encephalomyelitis (EAE). The incidence of EAE among rats with small, and moderate sized gliomas was similar to non-tumor-bearing controls (P less than 0.5; P less than 0.9) while 18 of 24 (75%) animals with large gliomas developed EAE as compared to 31 of 33 (93%) controls (P less than 0.05). The histologic features and geographical distribution of "ordinary' EAE were seen in controls and were maintained in tumor-bearing rats. The presence of an intracranial tumor did not significantly alter the ability of Lewis rats to develop EAE.