[T- and B-lymphocyte count in the spleen and lymph nodes of guinea pigs administered oxytetracycline intramuscularly].

The E and EAC rosette formation tests, carried out in order to determine the count of T and B lymphocytes in the spleen and lymph nodes of guinea pigs after several intramuscular of oxytetracycline, showed a decrease in the ability of B lymphocytes in the reaction of EAC rosette formation with the simultaneous rise of the level of "zero" cells without surface receptors characteristic of T and B lymphocytes. The data obtained in this study indicated the possibility for tetracyclines to effect the differntiation and ripening of the medullary precursors of B lymphocytes.