In vitro lysis of islet cells by lymphocytes from diabetic BB/Wor rats is not antibody mediated.
The role of pancreatic islet cell directed, antibody dependent cell mediated cytotoxicity (ADCC) in the development of diabetes was investigated in the spontaneously diabetic BB/Wor rat. Specific lysis of BB/Wor rat islet cells by effector splenic lymphocytes from acutely diabetic (AD) BB/Wor and control Wistar Furth (WF) rats in a 51Cr release assay was evaluated using four different ADCC assay protocols: two involved the pre-incubation, in the assay wells, of effector or target cells with heat inactivated sera from diabetic or control rats (1:10 dilution) prior to the addition of target or effector cells, respectively. The other two protocols involved the pre-incubation of effector or target cells with a 1:10 dilution of sera from diabetic or control rats, followed by two washes, prior to their addition into serum-free assay wells containing target or effector cells, respectively. The antibodies most likely to be involved in islet directed ADCC are the islet cell surface antibodies (ICSA), which have previously been demonstrated in the sera of diabetic rats; their presence in the diabetic sera used in these assays was confirmed. In the absence of serum pretreatment of either effector or target cells, specific lysis of islet cell targets by AD effector cells was 32.0 +/- 1.4% (n = 34), while specific lysis by control WF effector cells was 9 +/- 1.4% (n = 19), p less than 0.001. In no instance in any of the ADCC assays did the pre-treatment with AD (or WF) sera significantly increase target cell lysis.(ABSTRACT TRUNCATED AT 250 WORDS)
Koevary
S B
SB
Department of Cell Biology, University of Massachusetts Medical School, Worcester 01655.
D000818:Animals; D000920:Antibody-Dependent Cell Cytotoxicity; D001323:Autoantibodies / Q000032:analysis; D003602:Cytotoxicity, Immunologic; D003921:Diabetes Mellitus, Experimental / Q000276:immunology*; D007515:Islets of Langerhans / Q000276:immunology*; D008214:Lymphocytes / Q000276:immunology*; D051381:Rats; D011913:Rats, Inbred BB; D011920:Rats, Inbred WF; D013154:Spleen / Q000276:immunology
D001323:Autoantibodies; C024211:islet cell antibody