Antigen-nonspecific and specific suppression of lymphokine production in desensitized guinea pigs

Abstract

Doubly immunized guinea pigs may be desensitized with respect to delayed hypersensitivity reactions against both antigens (anergy) by injection of large doses of either one. This anergic response therefore has both a specific and nonspecific component. The specific component of desensitization persists longer than the nonspecific one. In the present study, we have explored the mechanism of both antigen-specific and antigen-nonspecific suppression during the later stages of desensitization. Guinea pigs imnmunized with two antigens, DNP-KLH and DNP-EA, were desensitized with DNP-EA. The lymph node cells obtained from the animals 1 day after desensitization were unable to produce MIF in the presence of either antigen. The cells obtained 3, 5, and 7 days after desensitization were able to generate MIF when stimulated with the non-specific antigen (DNP-KLH), but not with specific antigen (DNP-EA). It was shown that both T- and non-T-cell fractions obtained 1 day after desensitization had the capacity to antigen-nonspecifically suppress MIF production. In contrast, if the cells were obtained 3 or 5 days after desensitization, T cells could inhibit only the antigen-specific production of MIF, while non-T cells were still capable of suppressing antigen-specific and nonspecific MIF production. Interestingly, when these two populations were mixed back again, it was now only suppressive to the specific antigen-induced MIF production. This latter observation indicates that nonspecific suppressor non-T cells may themselves be regulated by suppressor T cells. Furthermore, antigen-specific suppressor T cells were shown to produce soluble factor(s) which inhibited the production of MIF.