Thyroglobulin-binding lymphoid cells in obese strain (OS) chickens

Area of Science:

• Immunology
• Endocrinology
• Veterinary Science

Background:

• Spontaneous autoimmune thyroiditis is a complex condition.
• Obese strain (OS) chickens naturally develop autoimmune thyroiditis.
• Lymphoid cell interactions with thyroglobulin are key to understanding thyroid autoimmunity.

Purpose of the Study:

• To analyze the binding of thyroglobulin-coated red blood cells by lymphoid cells in OS chickens.
• To determine the role of thyroglobulin-rosette-forming cells in the development of autoimmune thyroiditis.
• To characterize the cell types involved in thyroglobulin binding.

Main Methods:

• Rosette formation assay using chicken thyroglobulin-coated chicken red blood cells.
• Comparison of lymphoid cell counts in OS chickens and normal controls.
• Inhibition experiments using specific antisera to identify cell types.

Main Results:

• OS chickens exhibited significantly higher counts of thyroglobulin-rosette-forming cells in spleen and thymus compared to controls.
• Thyroglobulin-rosette-forming cell appearance preceded the onset and severity of thyroiditis and antibody production.
• Bursal lymphoid cell counts were similar in both OS and control chickens.
• Inhibition studies identified active thyroglobulin-rosette-forming cells as B cells and passive ones as T cells.

Conclusions:

• The presence of thyroglobulin-rosette-forming cells is a prerequisite for spontaneous autoimmune thyroiditis development in OS chickens.
• Thyroglobulin-rosette-forming cells, particularly B cells, play a critical role in the pathogenesis of autoimmune thyroiditis.
• These findings provide insights into the early immune events preceding autoimmune thyroiditis.