title: Possible toxic effects of normal and diabetic patient serum on pancreatic B-cells.
abstract: Serum from normal blood-donors and juvenile diabetic patients inhibited Rb+ accumulation and stimulated release of 51Cr and insulin in suspensions of dispersed pancreatic islet cells prepared from ob/ob mouse islets, which are rich in B-cells. The effects indicate the presence of a B-cytotoxic factor in human serum. Serum from mouse and fetal calf also inhibited the islet cell accumulation of Rb+. Toxicity was not suppressed by treating serum with protein A-Sepharose and did not correlate with islet cell binding of fluorescent antibodies to human immunoglobulin. Whereas all sera inhibited Rb+ accumulation, 3 of 6 diabetic patient sera, but no blood-donor serum, made the cells fluoresce on exposure to the fluorescent antibodies. Supporting a dependence on complement, toxicity remained after dialysis, but was destroyed by treating serum with zymosan-A or heating at 56 degrees for 30 min.
mesh_terms: D000818:Animals; D000906:Antibodies; D001402:B-Lymphocytes / Q000276:immunology*; D002860:Chromium Radioisotopes; D003602:Cytotoxicity, Immunologic; D003922:Diabetes Mellitus, Type 1 / Q000097:blood*; D005455:Fluorescent Antibody Technique; D006168:Guinea Pigs; D006801:Humans; D007328:Insulin / Q000378:metabolism; D007515:Islets of Langerhans / Q000276:immunology* / Q000378:metabolism; D051379:Mice; D011868:Radioisotopes; D012413:Rubidium
chemical_list: D000906:Antibodies; D002860:Chromium Radioisotopes; D007328:Insulin; D011868:Radioisotopes; D012413:Rubidium