Prevention of diabetes and induction of non-specific suppressor cell activity in the BB rat by an immunomodulatory azaspirane, SK&F 106610.
Immunomodulatory azaspirane compounds have immunosuppressive activity in animal models of autoimmune disease such as adjuvant-induced arthritis and experimental autoimmune encephalomyelitis. The mechanism of action of azaspiranes appears to be the induction of antigen non-specific (natural) suppressor cell activity. In this study, we tested the azaspirane, SK&F 106610 in an animal model of autoimmune (type 1) diabetes, the BB rat. Oral administration of SK&F 106610 (15 mg/kg/day) to diabetes-prone BB rats, from age 30 days, significantly decreased diabetes incidence at 100 days from 80% (24 of 30 control rats) to 32% (10 of 31 drug-treated rats, P < 0.001). Protection from diabetes by SK&F 106610 was accompanied by decreased lymphocytic infiltration of the pancreatic islets (insulitis). No changes occurred in splenic T cell, B cell or macrophage subsets, or in proliferative responses to the mitogens lipopolysaccharide and concanavalin A (Con-A). Cell mixing experiments in vitro, however, revealed increased antigen non-specific suppressor activity (suppression of splenic lymphoproliferative response to Con-A) in spleens of SK&F 106610-treated rats. The suppressor cell activity was enriched in a low density fraction of splenic cells relatively depleted of T cells, B cells, macrophages and natural killer cells. These results indicate that the azaspirane compound, SK&F 106610 can prevent insulitis and autoimmune diabetes in BB rats and that these actions may be related to the activation of non-specific (natural) suppressor cells.
Rabinovitch
A
A
Department of Medicine, University of Alberta, Edmonton, Canada.
Suarez
W L
WL
Qin
H Y
HY
Power
R F
RF
Badger
A M
AM
D000284:Administration, Oral; D000818:Animals; D001327:Autoimmune Diseases / Q000276:immunology / Q000473:pathology / Q000517:prevention & control*; D003922:Diabetes Mellitus, Type 1 / Q000276:immunology / Q000473:pathology / Q000517:prevention & control*; D005260:Female; D016130:Immunophenotyping; D007166:Immunosuppressive Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D007515:Islets of Langerhans / Q000473:pathology; D008213:Lymphocyte Activation; D016131:Lymphocyte Subsets / Q000276:immunology; D008297:Male; D010880:Piperidines / Q000008:administration & dosage / Q000627:therapeutic use*; D051381:Rats; D011913:Rats, Inbred BB / Q000276:immunology*; D013141:Spiro Compounds / Q000008:administration & dosage / Q000627:therapeutic use*; D013154:Spleen / Q000276:immunology; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*
D007166:Immunosuppressive Agents; D010880:Piperidines; D013141:Spiro Compounds; C080395:SK&F 106610