K-Cell activity in lamina proprial lymphocytes from the human colon

Using an enzymatic method for their isolation, it has been shown that human colonic lamina proprial lymphocytes, isolated from patients with various colonic diseases and depleted of polymorphonuclear leukocytes and macrophages, demonstrated K-cell activity in two antibody-dependent cell-mediated cytotoxicity assays in vitro. No differences were found between the activities of lamina proprial lymphocytes isolated from colonic specimens involved by Crohn's disease, chronic ulcerative colitis, or colonorectal carcinoma. K-cell activity was demonstrable using lymphoid cells isolated from the colons of patients receiving steroid therapy at the time of the therapeutic resections. These findings indicate the need for further investigation of possible roles for K-cells in local immune responses in the human bowel mucosa in inflammatory and neoplastic diseases.