Comparative study of immunomodulatory properties of muramyl peptides on immune system cells of young and old mice.

The immunomodulatory effects of two synthetic muramyl peptides (MP): muramyl dipeptide and glucosaminyl- muramyl dipeptide have been compared. It was shown, that MP effects on immune response are a consequence of the alteration in T lymphocyte regulators balance. MP action on old mice immune response and lymphocyte function was stimulating only: increasing of T helper precursors frequency and IL-1 production by macrophages. In the latter both MPs acted as correctors, recovering the decreased IL-1 production by old mice macrophages to young control level.