T lymphocyte subpopulations and immunoglobulin-containing cells in the colonic mucosa of ulcerative colitis; a morphometric and immunohistochemical study.

T lymphocyte subpopulations and immunoglobulin containing cells in the colonic mucosa of 25 patients with ulcerative colitis have been studied using an indirect immunoperoxidase technique. In ulcerative colitis a marked increase in the population of Leu 3a positive cells (helper/inducer T cells) and IgG containing cells was observed in the mucosal lamina propria. In the intraepithelial spaces, a remarkable decrease in the population of Leu 2a positive cells (suppressor/cytotoxic T cells) and a marked increase in the number of Leu 3a positive cells were revealed. There was a very significant correlation between the population of IgG containing cells and the ratio of Leu 3a positive cells to Leu 2a positive cells in the lamina propria of patients with ulcerative colitis. These results suggest that an imbalance of mucosal immunoregulatory T cells and an increased production of IgG occurred in correlation with inflammatory activities of ulcerative colitis.