Splenic Influence of T Cell Function: The Immunobiology of the Inbred Hereditarily Asplenic Mouse

Abstract
The influence of the spleen on the maturation of T cell function was investigated by using hereditarily asplenic mice inbred on a B6.CBA background. Asplenic (Dh/+), in contrast to +/+ littermate control mice, manifest a major qualitative deficiency of T cell function as well as a quantitative reduction in serum immunoglobulins. In particular, Dh/+ thymocytes are not as efficient as +/+ thymocytes in synergizing with either Dh/+ or +/+ bone marrow cells in the primary response to SRBC in irradiated littermate +/+ controls. This latter defect in T cell-bone arrow synergism was markedly age dependent and was evident only in young mice. Similarly, the DNA synthetic response of Dh/+ thymocytes injected into lethally irradiated BALB/c mice was quantitatively diminished in comparison to +/+ thymocytes when spleen and lymph nodes were quantitated. Spleen cell-seeking patterns of Dh/+ thymocytes were reduced compared to +/+ control cells when injected into +/+ littermates. Surface marker and mitogen responsiveness of lymph node cells revealed an increase in ϑ-bearing and decrease in Ig-bearing cells in Dh/+ mice compared to +/+ controls. The mortality and morbidity of Dh/+ mice, when compared to +/+ mice, after the perinatal period were identical. However, Dh/+ mice were more susceptible than +/+ controls. This latter defect in T cell-bone marrow synergism cogenesis. Cell reconstitution studies and serial age studies in mice receiving either MSV or polyoma virus confirmed the above observations regarding an age-dependent qualitative defect in T cell function. It is concluded that the spleen significantly effects the rate of murine T cell maturation.