title: The local immune response to large bowel tumors.
abstract: Methods are described for the purification on isokinetic gradients of isolated large bowel lamina propria lymphocytes (LPL) and large bowel adenocarcinoma-infiltrating lymphocytes (TIL). The in vitro cytotoxic and proliferative responses of these lymphocytes and of peripheral blood lymphocytes from tumor patients were assayed. Neither K cell nor NK cell cytotoxic activity was detected in LPL and TIL, although both types of lytic response were present in PBL. Lectin-induced cytotoxicity was mediated by LPL and TIL populations, but their responses in this assay were reduced comparable to that of PBL. Although TIL comprised equivalent T cell proportions to PBL, the proliferative response of TIL T cells was comparatively lower. LPL and TIL populations, but their responses in this assay were reduced comparable to that of PBL. Although TIL comprised equivalent T cell proportions to PBL, the proliferative response of TIL T cells was comparatively lower. Co-culture experiments and attempts to induce suppressor cells with concanavalin A suggested that the reduced proliferative response of T cells infiltrating these tumors was not due to the action of suppressor lymphocytes.
authors.forename: P W
authors.initials: PW
authors.lastname: Bland
mesh_terms: D000230:Adenocarcinoma / Q000276:immunology*; D000368:Aged; D000920:Antibody-Dependent Cell Cytotoxicity; D002430:Cecal Neoplasms / Q000276:immunology; D002469:Cell Separation; D003110:Colonic Neoplasms / Q000276:immunology; D005260:Female; D006801:Humans; D007414:Intestinal Neoplasms / Q000276:immunology*; D008214:Lymphocytes / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D012004:Rectal Neoplasms / Q000276:immunology; D012811:Sigmoid Neoplasms / Q000276:immunology; D050378:T-Lymphocytes, Regulatory / Q000276:immunology