Impairment of antibody response and of suppressor cell ontogenesis by early injection of hydrocortisone.

The appearance of antibody responsiveness against sheep red blood cells (SRBC) was studied in young mice treated with hydrocortisone hemisuccinate (HHC) either during gestation or around delivery (last 5 days of gestation or day of birth). The plaque forming cell (PFC) response was normal at 2 weeks and depressed at 4 weeks in animals treated during the last 10 days of pregnancy. Conversely, when HHC was only given around delivery, PFC response was depressed at 2 weeks and normal at 4 weeks. The presence of suppressor cells in unimmunized 1--2-week-old spleen cells was evaluated by co-culturing them with adult spleen cells from mice immunized against SRBC. Suppressive activity was found at high level at 8 days, and had already declined at 15 days in non-treated mice. Spleen cells from mice treated with HHC around delivery showed reduced suppressive activity at 8 days but this activity was very high on the 15th day, greater than in normal mice. Such highly suppressive activity correlated with a high level of Lyt-123 T cells. These data on suppressor cells indicate that the paradoxical effect of HHC in mice treated during gestation or around birth is probably explained by the differential effect of HHC on the kinetics of suppressor cells in ontogeny.