In the thymus of an animal model of type I diabetes, the population of regulatory T cells expresses a repertoire of antigen receptors that is approximately ten-fold less diverse than that found in mice resistant to autoimmune pathology. Genetic models later showed that this reduced diversity was involved in the susceptibility to diabetes. Researchers study the diversity of the TCR expressed by regulatory T cells from paediatric type I diabetes patients and controls. Regulatory T cells emigrated from the thymus will be isolated from the blood of patients and healthy controls. The repertoire of antigen-receptors will be analysed by high throughput sequencing and its diversity estimated using appropriate statistical models borrowed from ecology.
Regulatory T lymphocytes play a major role in the protection from autoimmune pathology. Defects in immunosuppression mediated by these cells is therefore suspected to contribute to these diseases. This issue has very little been studied in humans.Regulatory T cells emigrated from the thymus will be isolated from the blood of patients and healthy controls. The repertoire of antigen-receptors will be analysed by high throughput sequencing and its diversity estimated using appropriate statistical models borrowed from ecology.