Modulation of I-A and I-E expression in macrophages by T-suppressor cells induced in Cryptococcus neoformans infected rats.

When the I-A and I-E expressions were assessed in peritoneal macrophages from Cryptococcus neoformans infected animals, a significant decrease in the former was observed when compared with normal macrophages (p < 0.001) whereas a significant increase in the I-E expression was observed when compared with controls (p < 0.005). On the other hand, when studying the in vitro action of Ts cells on the macrophages, it was observed that the I-A expression was significantly reduced in macrophages upon contact with Ts cells. Similar results were obtained when Ts cells were replaced by a soluble factor. In contrast, the I-E expression was significantly increased by in vitro action of the Ts cell or its soluble factor. Indomethacin partially restored I-A and I-E expression in the macrophages to control levels.