Characteristics of Alloantigens and Cellular Mechanisms Responsible for Gamma-Interferon Production in Primary Murine MLC

We have investigated in primary murine MLC alloantigen differences and characteristics of responding cells responsible for γ-IFN production. Differences at K, D, or I-S-G regions stimulate γ-IFN release, though higher levels of production have been observed with differences at I-S-G regions. On the other hand, when mice differing in their minor histocompatibility antigens, notably at the MIs locus, were tested, γ-IFN production took place even between strain combinations not displaying lymphocyte proliferation. Lastly, using different cell depletion techniques, we demonstrate that T-lymphocytes are the cells producing γ-IFN upon stimulation with alloantigens. These findings show that T lymphocytes can recognize alloantigens by releasing γ-IFN even without displaying proliferation.