IMMUNONEUTRALIZATION OF GH IN NEONATAL RATS RESULTS IN DEFECTS IN LYMPHATIC TISSUES AND THE HUMORAL IMMUNE-RESPONSE

Neonatal female rats were treated for eight weeks with a well characte rized antiserum to rat growth hormone (anti-rGH) with or without repla cement therapy with recombinant bovine growth hormone (rbGH). Thymus a nd spleen weights, and cellularities, were significantly suppressed in these animals, whereas these effects were absent in those animals con currently treated with bGH. Animals treated with anti-rGH alone also e xhibited a reduced humoral response to donkey red blood cells but humo ral responses were normalized in animals receiving concurrent bGH trea tment. There were no significant differences in the mitogen responses of thymic or splenic lymphocytes from control or anti-rGH treated anim als. These data demonstrate the importance of GH in the development of both primary and secondary lymphoid tissues and humoral immunity.