Differential effect of hydrocortisone on lymphocyte populations in the mouse spleen.

The cellular composition of the spleen from CBA mice was investigated two days after administration of increasing doses of hydrocortisone acetate (HC), this using the presence of surface-immunoglobulin and the electrophoretic mobility as criteria for identification of lymphocyte populations. The B cell content was found to decrease more rapidly than did the T cell content. However, a significant diminution of the modal volume of both B and T cells was observed which suggests that HC acted similarly on each of these lymphocyte compartments by removing the larger elements. On the other hand, the in vitro reactivities to the B cell mitogens LPS and PPD were strongly depressed by HC injection while the reactivities to the T cell mitogens Con A and PHA remained relatively unchanged. Therefore, HC treatment appears to affect both B and T lymphocyte populations in the mouse spleen but the former to a greater extent than the latter.