Non-T cell-mediated cytolysis of antibody-coated sheep red blood cells requires Mg++ but not Ca++: An argument against a conventional "stimulus-secretion" mechanism for cytolysis.
"Stimulus-secretion" processes, and notably those in which the stimulus is provided by the formation of an antigen-antibody complex at the cell surface, require the presence of external Ca++. To test the possiblity that effector cells, in non-T cell mediated cytolysis, might be triggered to release a cytolytic product by a similar mechanism, we investigated the requirements of this phenomenon for divalent cations. We found that Ca++ is not sufficient, not necessary, and not inhibitory, whereas Mg++ is necessary and sufficient. Other cations were tested, and we found that Mn++ behaved like Mg++. The Ca++ data suggest that no conventional "stimulus-secretion" process is operative in non-T cell mediated cytolysis of antibody-coated sheep red blood cells.
D000818:Animals; D000906:Antibodies; D001402:B-Lymphocytes / Q000276:immunology*; D002118:Calcium / Q000502:physiology; D002413:Cations, Divalent; D002860:Chromium Radioisotopes; D003601:Cytotoxicity Tests, Immunologic; D004492:Edetic Acid; D004912:Erythrocytes / Q000276:immunology*; D008274:Magnesium / Q000502:physiology; D051379:Mice; D008809:Mice, Inbred C3H; D012756:Sheep / Q000276:immunology; D013154:Spleen / Q000166:cytology
D000906:Antibodies; D002413:Cations, Divalent; D002860:Chromium Radioisotopes; D004492:Edetic Acid; D008274:Magnesium; D002118:Calcium