We confirm and extend these previous observations CP 868596 using another marker
for regulatory T cells, namely the CD4+ cell population with low CD127 expression . Kekaleinen et al. revealed in their study that Tregs in patients with APS I do not function properly and that they have alterations in their TCR repertoire. All these data point towards a role of Tregs in the pathogenesis of APS I. We speculate that AIRE is involved in the development of Tregs, either in the thymus or in the lymph nodes where AIRE is also expressed [7, 8]. Thymic abnormalities could potentially also interfere with the proper development of iNKT cells – another type of cells with immunoregulatory properties. However, we could not confirm the previous reported decreases in iNKT  in Norwegian patients with APS I. Changes in the peripherally induced effector or memory cells could also reflect the autoimmune Alectinib mouse attack on endocrine organs. The percentage of the CCR4+CCR6+
Th-cell population which includes IL-17A producing Th17 cells was unaltered in patients with APS I in our study. This is in line with a previously published study on isolated CMC  and our recent report of unchanged IL-17A responses in spite of severely decreased IL-17F and IL-22 responses in APS 1 patients’ PBMC . IL17-producing cells have been reported to be involved in protection against Candida albicans (reviewed in ). These cells are also involved in the pathogenesis of many autoimmune diseases, including psoriasis, rheumatoid arthritis and Crohn’s disease [41–43]. Hence, patho-logical autoimmunity can be associated with an increased Th17-cell
response whereas a decreased function or number of these cells is correlated to CMC. The fact that patients with APS I are both susceptible for autoimmune diseases and for CMC might complicate the cellular analysis. Interestingly, we observed a significant decrease in CCR6+CXCR3+ Th-cell proportion Cobimetinib in patients with APS I. The mechanism underlying this phenomenon could be an increased homing of these cells to inflammatory tissues by binding to interferon-induced chemokines CXCL9 and 10; hence, these cells will be found in a decreased level in the circulation. Indeed, we have previously shown increased levels of CXCL10, a CXCR3 ligand, in APS I patient’s sera that is probably secreted by endothelial cells in inflamed tissues in response to IFNγ . The level of different DC subpopulations did not vary between the groups. This is in agreement of what we and others have published earlier [19, 38]. The monocyte level of patients with APS I has been shown by Hong et al. and Perniola et al. [19, 45] to be increased in patients compared to controls. The monocyte frequencies of patients varied a lot in our study, and some of the patients had indeed elevated numbers of these cells. However, when comparing the group as a unifying cohort, the results did not reach significance.