Regulatory T-Cell Panel, FOXP3

Regulatory T cells (Tregs) suppress the immune response, predominately through the transcription factor FOXP3.  The major Treg population is CD4+, CD25+, CD127- with expression of intracellular FOXP3. Decreased Tregs occur in autoimmune disorders including allergy and asthma.  Low numbers or compromised function of Tregs are found in graft vs host disease following bone marrow transplantation. Increasing Tregs is a potential cell therapy and decreasing Tregs may enhance immune surveillance of cancer cells. Monitoring Tregs may reflect the mechanism of disease and can assess the efficacy of treatment.

Severe FOXP3 compromise identified by low or absent Tregs is characteristic of the IPEX syndrome, which stands for immune dysregulation, polyendocrinopathy, enteropathy, and X-linked syndrome; however, some FOXP3 mutations may completely inhibit function yet still allow detection of the intracellular protein by immunologic methods, so absent Tregs by flow cytometry is sufficient, but not necessary for diagnosis.

Please note, reference intervals were established using normal adult donors aged 19 years and older. Therefore, clinical correlation of the results in pediatric patients is recommended.