Effect of histamine-receptor blocking on human natural and lectin-dependent cell-mediated cytotoxicity against adherent HEP-2 cells.
The effect of histamine (H) and H1-, H2-receptor blocking agents was studied on natural (NCMC) and lectin-dependent cell-mediated cytotoxicity (LDCC) of peripheral blood lymphocytes (PBL) from eight healthy subjects on HEP-2 adherent human epipharynx carcinoma target cells. Cytotoxicity was measured by detachment from the monolayer of 3H-TdR-prelabelled HEp-2 cells. LDCC was evaluated in a 24 h assay with a Concanavalin A (Con A) dose of 25 micrograms/ml at 50:1 effector-target cell ratio. Under these conditions, but without Con A, considerable NCMC was not elicited by normal lymphocytes. The presence of histamine and the H2-receptor blocker cimetidine resulted in a significant NCMC to HEp-2 cells. On the contrary, histamine and cimetidine reduced LDCC. The H1-receptor blocker clemastine had no significant effect on either NCMC or LDCC to HEp-2 targets. The possible involvement of H2-receptor bearing cells in the regulation of cytotoxicity to HEp-2 cells is suggested.
D002448:Cell Adhesion; D002460:Cell Line; D002927:Cimetidine / Q000494:pharmacology; D002974:Clemastine / Q000494:pharmacology; D003208:Concanavalin A / Q000494:pharmacology; D003602:Cytotoxicity, Immunologic / Q000187:drug effects*; D006632:Histamine / Q000494:pharmacology; D006633:Histamine Antagonists / Q000494:pharmacology*; D006801:Humans; D007113:Immunity, Innate / Q000187:drug effects; D066298:In Vitro Techniques; D008214:Lymphocytes / Q000187:drug effects* / Q000276:immunology; D010610:Pharyngeal Neoplasms / Q000276:immunology
D006633:Histamine Antagonists; D003208:Concanavalin A; D002927:Cimetidine; D006632:Histamine; D002974:Clemastine