Ontogeny of mouse lymphocyte function. II. Development of the ability to produce antibody is modulated by T lymphocytes

Abstract

The relative functional maturity of neonatal mouse spleen T and B cell populations was assessed by comparing their ability to respond to the thymic independent antigen, ε dinitrophenyl lysine (DNP) Ficoll, or thymic dependent sheep red blood cells (SRBC) by producing antibody in vitro. Although mouse spleen cells responded to DNP Ficoll at an earlier age than they responded to SRBC, or trinitrophenyl substituted (TNP) SRBC, the reason for the lag in the T dependent response was confounded by the finding of high numbers of suppressor T lymphocytes in the neonatal spleen. Thus, small numbers of neonatal spleen T cells or thymocytes significantly decreased the in vitro antibody response of adult spleen cells. Although B lymphocytes appear to be functionally mature soon after birth, their activity may be modulated by an excess of suppressor T cells; e.g. the reconstitution of helper cell function in the neonatal spleen required anti theta treatment before addition of adult helper cells. Suppressive activity attributable to T cells seems to play a dominant role in determining the ability of the neonatal animal to react positively or negatively to antigenic stimulation.