A relationship between the generation of burn-associated type 2 T cells and their antagonistic cells in thermally injured mice

Anti-type 2 T cells, generated in the spleens of thermally injured mice following the appearance of burn-associated CD8⁺, CD11b⁺, TCRγ/δ⁺ type 2 T cells (BA2T cells), have previously been shown to improve the resistance of thermally injured mice to Herpes virus infections. Anti-type 2 T cells, CD4⁺, CD28⁺, TCRα/β⁺, IFN-γ-producing T cell, are able to counteract the activity of BA2T cells which have been shown to be key cells in the increased susceptibility of thermally injured mice to these infections. In the present study, part of the generation mechanisms of anti-type 2 T cells was examined in mice. Anti-type 2 T cells were detected in the spleens of unburned mice 3-7 days after i.v. inoculation (2 x 10⁶ cells/mouse) of BA2T cells or a BA2T cell clone, defined as T6S cells. The suppressor cell activity of T6S cells was completely inhibited when they were co-cultured with anti-type 2 T cells from mice inoculated with T6S cells. Similar phenotypic and biological profiles of anti-type 2 T cells acquired from burned mice were expressed by T6S cell-induced anti-type 2 T cells. These results indicated that anti-type 2 cells may be generated in response to the appearance of BA2T cells in thermally injured mice. Immunoregulatory circuits may be involved in the generation of anti-type 2 T cells.