10.3389/fimmu.2018.00291.s001 Kostas Patas Kostas Patas Anne Willing Anne Willing Cüneyt Demiralay Cüneyt Demiralay Jan Broder Engler Jan Broder Engler Andreea Lupu Andreea Lupu Caren Ramien Caren Ramien Tobias Schäfer Tobias Schäfer Christian Gach Christian Gach Laura Stumm Laura Stumm Kenneth Chan Kenneth Chan Marissa Vignali Marissa Vignali Petra C. Arck Petra C. Arck Manuel A. Friese Manuel A. Friese Ole Pless Ole Pless Klaus Wiedemann Klaus Wiedemann Agorastos Agorastos Agorastos Agorastos Stefan M. Gold Stefan M. Gold Data_Sheet_1.PDF Frontiers 2018 adaptive immunity major depressive disorder chemokine receptors regulatory T cells T cell receptor repertoire 2018-02-20 04:23:22 Dataset https://frontiersin.figshare.com/articles/dataset/Data_Sheet_1_PDF/5902561 <p>While a link between inflammation and the development of neuropsychiatric disorders, including major depressive disorder (MDD) is supported by a growing body of evidence, little is known about the contribution of aberrant adaptive immunity in this context. Here, we conducted in-depth characterization of T cell phenotype and T cell receptor (TCR) repertoire in MDD. For this cross-sectional case–control study, we recruited antidepressant-free patients with MDD without any somatic or psychiatric comorbidities (n = 20), who were individually matched for sex, age, body mass index, and smoking status to a non-depressed control subject (n = 20). T cell phenotype and repertoire were interrogated using a combination of flow cytometry, gene expression analysis, and next generation sequencing. T cells from MDD patients showed significantly lower surface expression of the chemokine receptors CXCR3 and CCR6, which are known to be central to T cell differentiation and trafficking. In addition, we observed a shift within the CD4<sup>+</sup> T cell compartment characterized by a higher frequency of CD4<sup>+</sup>CD25<sup>high</sup>CD127<sup>low/−</sup> cells and higher FOXP3 mRNA expression in purified CD4<sup>+</sup> T cells obtained from patients with MDD. Finally, flow cytometry-based TCR Vβ repertoire analysis indicated a less diverse CD4<sup>+</sup> T cell repertoire in MDD, which was corroborated by next generation sequencing of the TCR β chain CDR3 region. Overall, these results suggest that T cell phenotype and TCR utilization are skewed on several levels in patients with MDD. Our study identifies putative cellular and molecular signatures of dysregulated adaptive immunity and reinforces the notion that T cells are a pathophysiologically relevant cell population in this disorder.</p>