T cell receptor repertoire deciphers anti-tuberculosis immunity.

T cell induced cellular immunity is considered to be extremely important for the control of tuberculosis (TB). T cell receptor (TCR), the key component responsible for the specificity and clustering of T cells, holds the potential to advance our understanding of T cell immunity against TB infection. This review systematically expounded the study progressions made in the field of TB-relevant TCRs based on single cell sequencing together with GLIPH2 technology and initiated a comparison of the T cell distribution between peripheral blood and infected organs. We divided clonal expanded T cell clones into recirculation subsets and local subsets to summarize their distinctions in clonal abundance, TCR sequences and antigenic specificity. Notably, local expansion appears to drive the primary variances in T cell subsets between these two contexts, indicating the necessity for further exploration into the functions and specificity of local subsets.

The associations between DNA methylation and depression: A systematic review and meta-analysis.

BACKGROUND: Growing evidence suggests that epigenetic modification is vital in biological processes of depression. Findings from studies exploring the associations between DNA methylation and depression have been inconsistent. METHODS: A systematical search of EMBASE, PubMed, Web of Science, and PsycINFO databases was conducted to include studies focusing on the associations between DNA methylation and depression (up to November 1st 2021) according to PRISMA guidelines with registration in PROSPERO (CRD42021288664). RESULTS: A total of 47 studies met inclusion criteria and 31 studies were included in the meta-analysis. This meta-analysis found that genes hypermethylation, including BDNF (OR: 1.15, 95%CI: 1.01-1.32, I2 = 90 %), and NR3C1 (OR: 1.43, 95%CI: 1.09-1.87, I2 = 88 %) was associated with increased risk of depression. Significant association of SLC6A4 hypermethylation with depression was only found in the subgroup of using original data (OR: 1.09, 95%CI: 1.01-1.19, I2 = 52 %). BDNF hypermethylation could increase the risk of depression only in the Asian population (OR: 1.18, 95%CI: 1.01-1.40, I2 = 91 %), and significant associations of NR3C1 hypermethylation with depression were found in the group for depressive symptoms (OR: 1.34, 95%CI: 1.08-1.67, I2 = 85 %), but not for depressive disorder (OR: 1.89, 95%CI: 0.54-6.55, I2 = 94 %). LIMITATIONS: More studies are needed to explore the factors that might influence the estimates owing to the contextual heterogeneity of the pooling of included studies. CONCLUSIONS: It is noted that DNA hypermethylation, namely BDNF and NR3C1, is associated with increased risk of depression. The findings in this study could provide some material evidence for preventing and diagnosing of depression.