Differential Effects of Preirradiation on Adoptive Antibody Responses in DBA/2 and BALB/c Mice

Mice were lethally irradiated on the same day or 3 days prior to the infusion of syngeneic thymus and marrow cells. Mice were immunized with sheep erythrocytes and direct plaque-forming cells per spleen were determined 8 days after cell transfer. Preirradiation of hosts 3 days before cell transfer had varying effects on the level of adoptive antibody responses in mice of different strains: Responses of DBA/2 and DBA/1 were deficient, responses of CD2F1, B10, B10.D2, C3H, C3BF1 and SJL were unaffected, and responses of BALB/c, CBA, and 129 mice were enhanced. The defect in the antibody responses of DBA/2 hosts was dependent on the combination of a DBA/2 host and a DBA/2 cell inoculum. Differentiation of both DBA/2 thymus and marrow cells was deficient in the preirradiated DBA/2 host. This defect did not appear to be the result of loss of adherent cells from the preirradiated DBA/2 host. The enhanced antibody response observed in BALB/c mice appeared to be due to altered activity of BALB/c thymus cells. Preirradiated BALB/c or DBA/2 recipients reconstituted with BALB/c thymus cells and BALB/c or DBA/2 marrow cells showed enhanced antibody responses, while preirradiated BALB/c or DBA/2 recipients reconstituted with BALB/c marrow cells and DBA/2 thymus cells showed no change in degree of antibody responses when compared to control recipients. The preirradiated host had altered its ability to control BALB/c thymus cell activity; this lack of control may be due to loss of regulator cells from the host.