The analysis of circulating Tfr in patients with sarcoidosis showed that within the total pool of Treg of central memory with CD45RA-CCR7+ phenotype, the share of CXCR5+ Tregs was increased, whereas the share of CXCR5+ cells among thymic Tregs did not significantly differ from the values of the control group [19]. The gene discussed is TFRC; the disease is sarcoidosis.