Generation of low-dose paralysis in the absence of the ability to secrete antibody.

(CBA/N female x BALB/c male)F1 male mice carry an X-linked defect, originating from CBA/N mice, which renders them unable to generate an antibody response to SSS-III. Histocompatible (BALB/c female x CBA/N male) reciprocal F1 male hybrids do not carry the X-linked defect and therefore generate a readily detectable PFC response to SSS-III, which can be adoptively transferred into nonresponding reciprocal F1 male mice. In the present work, we show that this adoptive response could be inhibited in recipient (CBA/N female x BALB/c male)F1 male nonresponding mice in which low dose paralysis had been induced. Evidence is presented which indicates that such suppression is of host rather than donor cell origin. The capacity to develop low-dose paralysis, a phenomenon that is antigen specific and has been attributed to the action of suppressor T cells, indicates that nonresponding (CBA/N female x BALB/c male) F1 males (and presumably the CBA/N progenitor strain) have the ability to recognize this antigen. Furthermore, since these animals fail to make a serum antibody response to SSS-III, the signal that activates suppressor T cells cannot be circulating antibody or antigen-antibody complexes. These findings are most consistent with the view that low-dose paralysis of the response to SSS-III is not dependent on antibody-mediated feedback inhibition; rather, it is an active process mediated by suppressor T cells.