MiR-214 regulates CD3ζ expression in T cells.

INTRODUCTION: T-cell activation requires the T-cell receptor (TCR)-CD3 complex, which integrates and transduces signals. CD3ζ plays a vital role in TCR signalling by mediating T-cell activation. Abnormal CD3ζ expression is a common characteristic of haematological malignancies with T-cell immune dysfunction or autoimmune diseases. Targeted regulation of CD3ζ expression by either direct or indirect approaches is important for regulating T-cell activation. AIM OF THE STUDY: In this study, we focused on identifying miRNAs that may regulate CD3ζ expression. MATERIAL AND METHODS: Three microRNA target search algorithms (TargetScan, PicTar, and microrna.org) were used to identify hypothetical miRNAs that target CD3ζ in T cells. Of the predicted miRNAs, miR-214 was chosen and validated to determine whether miR-214 directly binds to the CD3ζ 3'-UTR and regulates CD3ζ expression by luciferase reporter assays, real-time PCR, and Western blotting. RESULTS: The results indicate that miR-214 specifically binds the CD3ζ 3'-UTR, and miR-214 mimics remarkably reduce the expression of CD3ζ in MOLT-4 cells. CONCLUSIONS: We identify for the first time that miR-214 targets expression in MOLT-4 cells, suggesting that miR-214 might negatively regulate T-cell activation by targeting CD3ζ.

Increased IFN-γ+ and TNF-α+ mucosal-associated invariant T cells in patients with aplastic anemia.

BACKGROUND: Aplastic anemia (AA) is known as an autoimmune disease in which T cell activation is aberrant. It has been reported that unconventional T cells, mucosal-associated invariant T (MAIT) cells, play an important role in several autoimmune diseases, but it is unclear if they are involved in AA. METHODS: In this study, we for the first time analyzed the proportions, phenotypes, and cytokine properties of MAIT cells in AA by flow cytometry. RESULTS: We found that the percentage of circulating MAIT cells was generally higher for CD3+ , CD8+ , and CD8- T cells in AA patients compared with healthy individuals. Moreover, the percentage of IL-18Rα-, NKG2D-, IFN-γ-, and TNF-α- positive MAIT cells was also significantly higher in AA patients. In addition, the percentage of IFN-γ+ CD3+ or TNF-α+ CD8- MAIT cells had a significant negative correlation with the absolute neutrophil count. CONCLUSIONS: We present the first observation of MAIT cells in patients with AA. MAIT cells are associated with a higher frequency of IFN-γ and TNF-α production and may contribute to the pathogenesis of AA.

Abnormal miR-214/A20 expression might play a role in T cell activation in patients with aplastic anemia.

Aberrant T cell activation is a major cause of aplastic anemia (AA) pathogenesis. Recent studies have shown that miRNAs regulate T cell activation and are involved in AA. A previous study found that miR-214 was significantly up-regulated upon T cell activation in a CD28-dependent fashion by targeting PTEN. However, the expression characteristics of miR-214 and its target genes in AA have not been defined. In this study, target genes for miR-214 were predicted and confirmed by bioinformatics and luciferase reporter assays. The expression levels of miR-214 and target genes were detected in 36 healthy individuals and 35 patients with AA in peripheral blood mononuclear cells by real-time quantitative reverse transcriptase-polymerase chain reaction. Bioinformatics and luciferase reporter assays identified that miR-214 could bind to the A20 3' untranslated regions. Significantly increased miR-214 and the decreased A20 expression level were detected in the AA patients compared with the healthy group. In addition, significantly increased miR-214 was found in non-severe aplastic anemia compared with severe aplastic anemia patients. These results suggested that the A20 gene was a potential target of miR-214, and elevated miR-214 might medicate T cell activation at least in part by regulating A20 expression in AA. We firstly confirmed that miR-214 regulated A20 expression, and aberrant miR-214/A20 expression might contribute to immunopathology in AA. The miR-214 expression might be used as a potential biomarker that assisted in diagnosing AA severity.

Prevalence of Post-Traumatic Stress Disorder Following Caesarean Section: A Systematic Review and Meta-Analysis.

Background: While caesarean section (CS) can be a lifesaving intervention when performed in a timely manner to overcome dystocia or other complications, it is a traumatic event and may increase the risk of post-traumatic stress disorder (PTSD). No attempt has been made to assess prevalence of PTSD after CS specifically. This study aimed to quantify pooled prevalence of PTSD after CS through a systematic review and meta-analysis. Methods: MEDLINE, PsycINFO, EMBASE, and CINAHL were searched using PTSD terms crossed with CS terms. Studies were included if they reported the prevalence of PTSD after CS using an instrument based on Diagnostic and Statistical Manual of Mental Disorders-criteria to identify PTSD. The pooled prevalence was then estimated by meta-analysis in overall eligible studies and in subgroups. Results: Nine studies were included with a total of 1,134 postpartum women, of which 136 were identified as having PTSD. Pooled prevalence of PTSD after CS was 10.7% (95% confidence interval [CI]: 4.0-20.2). Pooled prevalence of PTSD after emergency CS (10.3% [95% CI: 1.7-24.9]) was higher than that after elective CS (7.1% [95% CI: 0.7-19.4]), but the difference was not statistically significant. Subgroup analysis showed that pooled prevalence of PTSD after CS differed according to study setting, time interval of PTSD assessment, and type of participants. Meta-regression analysis showed that study setting and type of study participants were significant sources of heterogeneity. Conclusions: Women with CS apparently have higher rates of PTSD as compared with women without CS. However, the susceptibility to PTSD appears to vary based on emergency/elective CS, study methodology, self-perceived traumatic birth, and country of study. Further targeted research is needed to elucidate the role of these factors in relationship between CS and PTSD.

[Changes of CD3γ, CD3δ and CD3epsilon chains mRNAs in lead-poisoned patients after chelate treatment].

OBJECTIVE: To investigate the expressions of T cell receptor (TCR) signaling CD3γ, CD3δ and CD3epsilon chains in T cells from peripheral blood mononuclear cells (PBMCs) in lead-poisoned workers after chelate treatment. METHODS: The expression levels of CD3γ, CD3δ and CD3epsilon mRNAs in PBMCs from 16 lead-poisoned workers before and after chelate treatment and 9 healthy individuals were detected by real-time quantitative PCR. The ß2-microglobulin gene (ß2M) was used as an endogenous reference. Relative mRNA levels were calculated by the 2(-δCt)×100%. Spearman correlation analysis was used to estimate the correlations of different gene expression levels between healthy individuals and the patients as well as before and after the treatment. RESULTS: The CD3γ mRNA level in the lead-poisoned workers before and after chelate treatment has no significant difference as compared with that of the healthy individuals. The expression levels of CD3δ mRNA in the lead-poisoning workers before and after chelate treatment were remarkably lower than that of the healthy individuals. After chelate treatment, the CD3δ mRNA level in the lead-poisoned workers was lower than that before treatment. The CD3epsilon mRNA level in the lead-poisoned workers before treatment was obviously higher than that of the healthy individuals, while the expression level of CD3epsilon mRNA decreased after chelate treatment. There were no evident correlations between CD3γ and CD3δ, CD3γ and CD3epsilon, CD3δ and CD3epsilon mRNAs, while CD3γ and CD3δ, CD3γ and CD3epsilon, CD3δ and CD3epsilon mRNAs had markedly positive correlations in the lead-poisoned workers before chelate treatment, and only CD3δ and CD3epsilon had a significantly positive correlation after the treatment. CONCLUSION: The expression levels of CD3γ, CD3δ and CD3epsilon mRNAs in the lead-poisoned workers showed varied alterations, which indicated that lead poisoning had an impact on human immunity system and affected different genes in different ways. After chelate treatment, CD3δ mRNA level was still different from that of healthy individuals, which indicated that the function of the immunity system was still abnormal.

Molecular alterations in the TCR signaling pathway in patients with aplastic anemia.

BACKGROUND: A previous study has demonstrated a significantly increased CD3ζ gene expression level in aplastic anemia (AA). However, the mechanism underlying the upregulated CD3ζ mRNA expression level and that of T cell activation signaling molecules in AA patients remains unclear. Thus, we investigated the expression levels of the CD3ζ, CD28, CTLA-4, and Cbl-b genes, the SNP rs231775 in the CTLA-4 gene, and the distribution of the CD3ζ 3'-UTR splice variant in AA patients. METHODS: CD3ζ 3'-UTR splice variants were identified in peripheral blood mononuclear cells (PBMCs) from 48 healthy individuals and 67 patients with AA [37 cases of severe aplastic anemia (SAA) and 30 cases of non-sever aplastic anemia (NSAA)] by RT-PCR. CD3ζ, CD28, CTLA-4, and Cbl-b gene expression was analyzed by real-time quantitative PCR. The SNP rs231775 in CTLA-4 gene was analyzed by PCR-RFLP. RESULTS: CD3ζ and CD28 expression was significantly higher, while CTLA-4 and Cbl-b expression was significantly lower in AA patients compared with healthy individuals. Significantly higher CD3ζ expression was found in the NSAA subgroup compared with the SAA subgroup. 64 % of the AA samples had the same genotype (WT(+)AS(+)CD3ζ 3'-UTR); 22 % of the AA patients had a WT(+)AS(-)CD3ζ 3'-UTR genotype, and 14 % of the AA patients had a WT(-)AS(+)CD3ζ 3'-UTR genotype. The CD3ζ expression level of WT(-)AS(+) subgroup was the highest in the SAA patients. A significantly higher frequency of the GG genotype (mutant type, homozygous) of SNP rs231775 in CTLA-4 gene was found in the AA patients. Positive correlation between the CTLA-4 and Cbl-b gene expression levels was found in healthy individuals with the AA and AG genotypes, but not in the AA patients. CONCLUSIONS: This is the first study analyzing the expression characteristics of the CD28, CTLA-4, and Cbl-b genes in AA. Our results suggest that aberrant T cell activation may be related to the first and second signals of T cell activation in AA. The GG genotype of SNP rs231775 in CTLA-4 gene might be associated with AA risk in the Chinese population. The characteristics of CD3ζ 3'-UTR alternative splicing may be an index for evaluating the T cell activation status in AA patients, particularly in SAA patients.