ABSTRACT
This chapter discusses the spontaneous autoimmune diseases parallel the human diseases vitiligo, scleroderma, and Hashimoto's thyroiditis and will likely be instrumental in understanding these and other autoimmune diseases. It describes the thymocyte and T-cell hyperproliferation that was later found to be characteristic of the Obese strain (OS) chicken. Although antibody responses following immunizations seen thus far have not demonstrated any differences in antibody titer or response times between OS and other normal chicken strains, lymphokines secreted by hyperactive T cells might modulate preferential class switching, antigen-presenting capabilities, or B-cell activity and differentiation in general. Birds with B were first found to be low responders by Bacon et al., however, later inbreeding by Hal+á demonstrated B birds with severe disease probably due to the effect of non-major histocompatibility complex (MHC) genes. Among the examples of genetically determined autoimmune diseases in chickens are the Smyth-DAM line, which develop amelanosis resembling human vitiligo, and the UCD line 200 chicken which develops progressive systemic sclerosis.
