Effect of neonatal treatment with a GnRH antagonist on development of the cell-mediated immune response in marmosets

PROBLEM: We examined the effect of neonatal treatment with a gonadotropin-r eleasing hormone (GnRH) antagonist (antide) on the development of cell-medi ated immunity in male marmosets. METHOD OF STUDY: Neonatal marmoset twins were treated with either vehicle o r antide, and the proliferative response (PR) of lymphoid tissue to mitogen s was assessed during infancy, the peripubertal period, and adulthood. RESULTS: Basal proliferation of peripheral blood mononuclear cells (PBMC) f rom treated peripubertal twins was elevated above control values, but the P R of the cells to T and B cell mitogens was subnormal. Conversely, PBMC fro m treated infants exhibited an enhanced PR to some of the mitogens employed . In vitro culturing of thymocytes (control or treated) from the three deve lopmental stages with either antide or a GnRH agonist increased basal proli feration, but decreased the PR to mitogens by 60-80%. CONCLUSION: Neonatal treatment with antide alters development of, but does not permanently impair, cell-mediated immunity in the marmoset. GnRH appear s to modulate immune responses throughout development in the primate.