Effect of cyclosporin A on spontaneous autoimmune thyroiditis of Obese strain (OS) chickens.
The spontaneous autoimmune thyroiditis (SAT) which develops in the Obese strain (OS) of chickens depends on an intact B-dependent portion of immune system. T helper cells have been shown to be required for the production of thyroglobulin autoantibodies (Tg-AAb), but a possible contribution of cytotoxic T cells in the initial phases of SAT still remains to be elucidated. Cyclosporin A (CsA), an immunosuppressive drug with selective activity on T blast formation was used as a probe to clarify this issue: (a) the immunosuppressive potential of CsA was first verified for an avian species by demonstrating prolongation of skin allograft survival; (b) posthatching treatment of OS chickens with CsA until they were killed at 3 weeks of age did not alter the frequency and severity of SAT and the incidence and titer of Tg-AAb; (c) treatment of OS embryos on days 15, 17 and 19 of incubation entailed the development of significantly more severe disease and higher titers of Tg-AAb as compared to controls. A possible effect of CsA on precursors of suppressor T cells in the chicken is postulated. Cytotoxic T cells seem to play a minor role in the beginning of thyroid infiltration. It is concluded that CsA may not be the drug of choice for treatment of at least some autoimmune diseases.
D000284:Administration, Oral; D000818:Animals; D001327:Autoimmune Diseases / Q000188:drug therapy* / Q000196:embryology / Q000276:immunology; D002642:Chick Embryo; D002645:Chickens; D003524:Cyclosporins / Q000008:administration & dosage* / Q000097:blood / Q000627:therapeutic use; D004195:Disease Models, Animal; D006085:Graft Survival / Q000187:drug effects; D008297:Male; D016038:Skin Transplantation; D013961:Thyroid Gland / Q000473:pathology; D013966:Thyroiditis / Q000188:drug therapy* / Q000276:immunology
D003524:Cyclosporins