Forkhead box P3 (FOXP3) (FOXP3)

Forkhead box P3 (FOXP3) is a transcription factor that serves as the master regulator for the development and suppressive function of regulatory T cells (Tregs) (UniProt P63313). Primarily expressed in CD4+ T cells, FOXP3 is essential for maintaining immune homeostasis and self-tolerance by repressing the production of pro-inflammatory cytokines like IL-2 and upregulating suppressive markers such as CTLA-4 (Fontenot et al., 2003, PMID: 12612552). The FOXP3 locus is regulated by epigenetic modifications, specifically the methylation status of the Treg-specific demethylated region (TSDR), which determines the stability of the Treg lineage (Sakaguchi et al., 2007, PMID: 17200661). Mutations in the FOXP3 gene cause IPEX syndrome, a fatal multi-organ autoimmune disease, highlighting its critical role in preventing autoimmunity (NCBI Gene 50943). In cancer, FOXP3+ Tregs often accumulate in the tumor microenvironment, where they inhibit anti-tumor immunity and correlate with poor clinical outcomes. Therapeutic strategies include using low-dose IL-2 (Aldesleukin) or Sirolimus to expand FOXP3+ Tregs for treating autoimmune diseases and graft-versus-host disease, while research into FOXP3 inhibitors or Treg depletion is ongoing for cancer immunotherapy (Miyara et al., 2014, PMID: 25161031).

Other names

ScurfinIPEXJM2AIIDPIDXXPIDForkhead box protein P3

Transcriptional regulation of genes involved in regulatory T cell function and stabilization of the Treg phenotype.