T-regulatory cells in primary immune deficiencies

Purpose of review To summarize studies on the development and function of T-regulatory (T-R) cells in primary immune deficiencies (PIDs). Recent findings PIDs are associated with high rates of autoimmunity. T-R cells, which are critical to the control of autoimmunity, appear involved in the pathogenesis of PID-related autoimmunity. A number of PIDs, including Omenn's syndrome and Wiskott-Aldrich syndrome, have been associated with impaired production and/or function of thymus-derived (natural) T-R cells. Recently defined primary immunodeficiencies, including Stim1 deficiency, IL-10 receptor deficiency, and xIAP deficiency, have been associated with defects in T-R cells. De-novo generated T-R cells from peripheral CD4+ conventional T cells is impaired in the hyper IgE syndrome. Summary Gene defects underlying PIDs may also compromise the T-R cell, leading to breakdown of peripheral tolerance.