THE COURSE OF LCMV INFECTION IN EUTHYMIC AND ATHYMIC MICE PRETREATED WITH IMMUNOMODULATORY AGENTS

Balb/c (euthymic) and nu/nu (athymic) mice were treated intraperitonea lly with TP-4 (a synthetic tetrapeptid, thymopoietin sequence analog) or with Mannozym (1% zymosan suspension), and were infected intracereb rally with LCM virus. Both of the agents contributed to the developmen t of fatal choriomeningitis, consequently stimulated the cellular immu ne response in euthymic mice, but the athymic mice either treated or n ot, survived the infection, consequently the agents had no effect on t he course of LCM virus infection. Both agents exerted a thymus-depende nt cellular immune response stimulating effect. That is, an immunostim ulatory effect can be realized only in the presence of the thymus or t he T-dependent lymphoid system.