T-lymphopenia and T-cell imbalance in diabetic db/db mice.
The diabetic db/db mice of the C57 BL/KsJ strain display anti-islet immunity, thymic dysfunction, and lymphopenia. In the present work, lymphocytes, T-cells, and T-cell subsets were enumerated in thymus and spleen from diabetic db/db mice and their db/ + heterozygote littermates from the 10th day to the 10th month of life. A significant lymphopenia was detected in thymus and spleen from the second month on, involving specifically the T-cell compartment, as assessed by use of a monoclonal anti-Thy1 antibody in indirect fluorescence. The study of T-cell subsets by monoclonal anti-Lyt1 and anti-Lyt2 antibodies revealed a significant increase in Lyt1+ cells and a decrease in Lyt2+ cells, with a corresponding increase of the Lyt1+/Lyt2+ ratio. These anomalies appeared early in life, and were apparently linked neither with the degree of hyperglycemia nor with weight loss or infection. The T-cell depletion in thymus was more pronounced in young male (less than 3 mo) than in young female db/db mice. These alterations may correspond to an increase in the helper/suppressor-cytotoxic ratio and could be linked with the thymic anomalies present in these mice, contributing to the development of anti-islet autoimmunity.
D000818:Animals; D001323:Autoantibodies / Q000276:immunology; D001402:B-Lymphocytes; D001786:Blood Glucose / Q000032:analysis; D001835:Body Weight; D004285:Dogs; D007328:Insulin / Q000097:blood; D007515:Islets of Langerhans / Q000276:immunology; D007958:Leukocyte Count; D008231:Lymphopenia / Q000276:immunology*; D008264:Macrophages; D051379:Mice; D008810:Mice, Inbred C57BL / Q000276:immunology; D008820:Mice, Obese / Q000276:immunology*; D051381:Rats; D012737:Sex Factors; D013154:Spleen / Q000166:cytology; D013601:T-Lymphocytes; D013950:Thymus Gland / Q000166:cytology
D001323:Autoantibodies; D001786:Blood Glucose; D007328:Insulin