Splenic leukocytes from chickens injected with Salmonella pullorum antigen stimulate production of corticosteroids by isolated adrenal cells.

Corticosteroid levels in the blood serum of White Rock pullets were significantly increased within 1 hr after an iv injection of heat-killed Salmonella pullorum antigen (SP-Ag), and reached levels 7 to 10 times that of PBS-injected controls within 2 hr after SP-Ag injection. Incubations with isolated adrenal cells indicated that serum from SP-Ag-injected birds had the ability to stimulate the synthesis or release of corticosteroids twice that of serum PBS-injected birds. Stripping the serum from SP-Ag-injected birds with activated charcoal and precipitated silica (Quso G-32) removed the corticosteroids and the adrenal-stimulating ability. A 2-hr incubation of isolated adrenal cells with leukocytes from spleens removed from chickens 1 hr after injection with SP-Ag, using stripped serum as the medium, stimulated a two- to fivefold increase in corticosteroid as compared to splenic leukocytes from PBS-injected chickens incubated in the same medium. The results indicate that an "ACTH-like" substance was produced by the S. pullorum antigen-stimulated splenic leukocytes.