Effects of immunoagents on circulating serum hemolysin formation in bone marrow and spleen

The bone marrow as a source of serum hemolysin to sheep red blood cells (SRBC) was studied in splenectomized mice. Splenectomy prevented the hemolysin formation in the primary response, but not in the secondary response. Cyclophosphamide 100 mg/kg and dexamethasone 10 mg/kg decreased hemolysin formation in the bone marrow as well as in the spleen. Levamisole 50 mg/kg increased its formation in both organs. Prednisolone 10 mg/kg significantly suppressed its formation in the spleen, but not in the bone marrow. Hydroxyurea 50 mg/kg suppressed its formation in the bone marrow, but not in the spleen. These results suggest that the bone marrow is the major source of serum hemolysin to SRBC during the secondary response and drug has different effects on antibody production in the bone marrow and in the spleen.