Exploring the therapeutic potential of regulatory T cell in rheumatoid arthritis: Insights into subsets, markers, and signaling pathways

Rheumatoid arthritis (RA) is a complex autoimmune inflammatory rheumatic disease characterized by an imbalance between immunological reactivity and immune tolerance. Regulatory T cells (Tregs), which play a crucial role in controlling ongoing autoimmunity and maintaining peripheral tolerance, have shown great potential for the treatment of autoimmune inflammatory rheumatic diseases such as RA. This review aims to provide an updated summary of the latest insights into Treg-targeting techniques in RA. We focus on current therapeutic strategies for targeting Tregs based on discussing their subsets, surface markers, suppressive function, and signaling pathways in RA.

Efficacy and safety of bimekizumab in the treatment of psoriatic arthritis: a systematic review and meta-analysis

BACKGROUND

Bimekizumab, a humanized monoclonal IgG1 antibody targeting both interleukin (IL)-17A and IL-17F, could be effective for treating Psoriatic arthritis (PsA). This study aimed to systematically evaluate the efficacy and safety of bimekizumab in the management of PsA.

RESEARCH DESIGN AND METHODS

A comprehensive literature search by August 2023 was performed through PubMed, Embase, Cochrane Controlled Register of Trials, and ClinicalTrials.gov. investigating the efficacy or safety data of bimekizumab in the treatment of PsA. Data was pooled using the random-effects models. Egger tests were used to evaluate potential publication bias.

RESULTS

A total of 4 RCTs, involving 892 PsA patients and 467 placebo controls, were included in this analysis. Bimekizumab significantly increased the rates of PASI75 and PASI100 compared with placebos [RR = 7.22, 95% CI (5.24, 9.94), p < 0.001; RR = 10.12, 95% CI (6.00, 17.09), p < 0.001]. The rate of overall adverse events was slightly higher in the bimekizumab group [RR = 1.42, 95% CI (1.05, 1.93) p = 0.023). However, there were fewer adverse severe drug reactions in the bimekizumab group compared to the placebo.

CONCLUSION

Bimekizumab had a significant clinical benefit in managing PsA and an acceptable safety profile.

Efficacy and Safety of Risankizumab in Patients with Psoriatic Arthritis: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

INTRODUCTION

Currently, the cause of psoriatic arthritis (PsA) is unknown, and the effectiveness of current drug treatments is unsatisfactory. In March 2019, the US Food and Drug Administration (FDA) approved risankizumab, a humanized immunoglobulin G1 (IgG1) monoclonal antibody targeting the p19 subunit of interleukin (IL)-23, for the treatment of PsA in adults. This study aimed to conduct a meta-analysis of double-blind, randomized, placebo-controlled trials to evaluate the effectiveness and safety of risankizumab in moderate-to-severe PsA.

METHODS

We conducted a thorough search of relevant databases from the establishment of the databases to October 1, 2023. We conducted a meta-analysis using Stata 12.0 and utilized I2 and Egger tests to assess heterogeneity and publication bias among the studies. Bias assessment was performed using the risk bias map and bias risk summary diagram generated by Revman5.4 software. The review protocols were registered on PROSPERO (CRD42023451894) and adhered to the preferred reporting item of system evaluation (PRISMA) guideline.

RESULTS

Six randomized controlled trials (RCTs) involving 5038 patients with PsA treated with either risankizumab or placebo were included in the analysis. At 24 weeks, the risankizumab group demonstrated a significantly higher American College of Rheumatology-20 (ACR20) response rate compared to the placebo group (RR 1.760, 95% CI 1.568-1.977, P < 0.001). Additionally, the risankizumab group showed a significantly higher Minimal Disease Activity (MDA) response rate compared to the placebo group (RR 1.827, 95% CI 1.048-3.184, P < 0.05). The risankizumab group also exhibited improvement in Short Form 36 Questionnaire (SF-36) score (SMD 0.51, 95% CI 0.33-0.69, P < 0.001), with significantly lower Health Assessment Questionnaire Disability Index (HAQ-DI) score (SMD - 0.27, 95% CI - 0.37 to - 0.17, P < 0.001) and higher Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F) score (SMD 0.27, 95% CI 0.20-0.35, P < 0.001) compared to the placebo group. Moreover, the risankizumab group had a significantly lower Psoriasis Area and Severity Index (PASI) score (SMD - 6.12, 95% CI - 10.02 to 2.23, P < 0.001). A study by Mease et al. indicated that patients receiving risankizumab generally demonstrated numerical improvements in the Leeds Enthesitis Index (LEI), although the small sample size limits the evidence. Further research is necessary to provide evidence-based guidelines. There were no significant differences in the incidence of serious adverse events (SAE) and serious treatment-emergent adverse events (STEAE) between the risankizumab and placebo groups (RR 0.76, 95% CI 0.45-1.28, P = 0.31; RR 0.99, 95% CI 0.49-1.99, P = 0.97, respectively), and the overall incidence of adverse events (AE) was not comparable (RR 1.10, 95% CI 0.63-1.94, P = 0.73).

CONCLUSION

Risankizumab showed superior efficacy across multiple outcome measures compared to placebo, with no significant increase in adverse events. Our findings endorse risankizumab as an excellent treatment option for PsA, offering valuable insights for clinicians and patients when choosing appropriate therapeutic interventions.

TRIAL REGISTRATION

Retrospectively registered (CRD42023451894, 16 August 2023).

Genetic prediction of modifiable lifestyle factors for erectile dysfunction

Background

The causal relationship between certain lifestyle factors and erectile dysfunction (ED) is still uncertain.

Aim

The study sought to investigate the causal effect of 9 life factors on ED through 2-sample single-variable Mendelian randomization (SVMR) and multivariable Mendelian randomization (MVMR).

Methods

Genetic instruments to proxy 9 risk factors were identified by genome-wide association studies. The genome-wide association studies estimated the connection of these genetic variants with ED risk (n = 223 805). We conducted SVMR, inverse variance-weighting, Cochran's Q, weighted median, MR-Egger, MR-PRESSO (Mendelian Randomization Pleiotropy RESidual Sum and Outlier), and MVMR analyses to explore the total and direct relationship between life factors and ED.

Outcomes

The primary outcome was defined as self or physician-reported ED, or using oral ED medication, or a history of surgery related to ED.

Results

In SVMR analyses, suggestive associations with increased the risk of ED were noted for ever smoked (odds ratio [OR], 5.894; 95% confidence interval [CI], 0.469 to 3.079; P = .008), alcohol consumption (OR, 1.495; 95% CI, 0.044 to 0.760; P = .028) and body mass index (BMI) (OR, 1.177; 95% CI, 0.057 to 0.268; P = .003). Earlier age at first intercourse was significantly related to reduced ED risk (OR, 0.659; 95% CI, -0.592 to -0.244; P = 2.5 × 10-6). No strong evidence was found for the effect of coffee intake, time spent driving, physical activity, and leisure sedentary behaviors on the incidence of ED (All P > .05). The result of MVMR analysis for BMI (OR, 1.13; 95% CI, 1.01 to 1.25; P = .045) and earlier age at first intercourse (OR, 0.77; 95% CI, 0.56 to 0.99; P = .018) provided suggestive evidence for the direct impact on ED, while no causal factor was detected for alcoholic drinks per week and ever smoked.

Clinical implications

This study provides evidence for the impact of certain modifiable lifestyle factors on the development of ED.

Strengths and limitations

We performed both SVMR and MVMR to strengthen the causal relationship between exposures and outcomes. However, the population in this study was limited to European ancestry.

Conclusion

Ever smoked, alcoholic drinks per week, BMI, and age first had sexual intercourse were causally related to ED, while the potential connection between coffee intake, physical activity, recreational sedentary habits, and increased risk of ED needs to be further confirmed.

Causal association between JAK2 and erectile dysfunction: a Mendelian randomization study

BACKGROUND

As one of the most critical proteins in the JAK/STAT signaling pathway, Janus kinase 2 (JAK2) is involved in many biological processes and diseases. Several observational studies have reported the role of JAK2 in erectile dysfunction. However, the causal relationship between JAK2 and erectile dysfunction remains unclear. Here we investigated the causal relationship between JAK2 and erectile dysfunction.

RESULTS

Genetically predicted JAK2 was causally associated with erectile dysfunction in inverse variance weighting (OR = 1.109, 95% CI = 1.029-1.196, p = 0.007) and weighted median method (OR = 1.117, 95% CI = 1.003-1.245, p = 0.044). No heterogeneity was observed in Cochran Q-test (p = 0.855) and MR-PRESSO (p = 0.866). Pleiotropy was not observed in our study (p = 0.617).

CONCLUSIONS

These findings highlighted JAK2 as a risk factor for erectile dysfunction and proved the causal relationship between JAK2 and erectile dysfunction, suggesting that targeting JAK2 signaling might be a novel and promising therapeutic candidate in the treatment of erectile dysfunction.

Low-dose IL-2 improved clinical symptoms by restoring reduced regulatory T cells in patients with refractory rheumatoid arthritis: A randomized controlled trial

Background

Regulatory T cells (Tregs) have been found to play crucial roles in immune tolerance. However, the status of Tregs in refractory rheumatoid arthritis (RA) is still unclear. Moreover, low-dose interleukin-2 (IL-2) has been reported to selectively promote the expansion of Tregs. This study investigated the status of CD4⁺ Tregs and low-dose IL-2 therapy in patients with refractory RA.

Methods

The absolute number of CD4⁺CD25⁺FOXP3⁺ Treg (CD4 Treg), CD4⁺IL17⁺ T (Th17), and other subsets in peripheral blood (PB) from 41 patients with refractory RA and 40 healthy donors was characterized by flow cytometry combined with an internal microsphere counting standard. Twenty-six patients with refractory RA were treated with daily subcutaneous injections of 0.5 million IU of human IL-2 for five consecutive days. Then, its effects on CD4 Treg and Th17 cells in PB were analyzed.

Results

A decrease in the absolute number of PB CD4 Tregs rather than the increase in the number of Th17 was found to contribute to an imbalance between Th17 and CD4 Tregs in these patients, suggesting an essential role of CD4 Tregs in sustained high disease activity. Low-dose IL-2 selectively increased the number of CD4 Tregs and rebalanced the ratio of Th17 and CD4 Tregs, leading to increased clinical symptom remission without the observed side effects.

Conclusions

An absolute decrease of PB CD4 Tregs in patients with refractory RA was associated with continuing disease activation but not the increase of Th17 cells. Low-dose IL-2, a potential therapeutic candidate, restored decreased CD4 Tregs and promoted the rapid remission of patients with refractory RA without overtreatment and the observed side effects.

Clinical trial registration

http://www.chictr.org.cn/showproj.aspx?proj=13909, identifier ChiCTR-INR-16009546.

Levels of Peripheral Th17 Cells and Th17-Related Cytokines in Patients with Ankylosing Spondylitis: A Meta-analysis

BACKGROUND

Ankylosing spondylitis (AS) is a chronic inflammatory disease. Several proinflammatory cytokines produced by T helper 17 (Th17) cells are involved in the pathogenesis of AS. We performed a meta-analysis to determine the levels of Th17 cells and serum Th17-associated cytokines in patients with AS.

METHODS

We determined the levels of Th17 cells and Th17 cytokines in patients with AS using data extracted from published articles retrieved from the PubMed, Embase, Web of Science, Cochrane Library, MEDLINE, Web of Knowledge, Clinical Trials.gov, and FDA.gov.

DATABASES

The effect estimates were pooled using a random-effects model. The review protocols were registered on PROSPERO (reference: CRD42021255741) and followed the PRISMA guideline.

RESULTS

This meta-analysis included 138 studies. Compared to healthy controls (HCs), patients with AS had a higher proportion of Th17 cells (standardized mean difference [SMD] 2.23, 95% confidence interval [CI] 1.78-2.68; p < 0.001) and levels of proinflammatory cytokines, such as interleukin (IL)-17 (SMD 2.04, 95% CI 1.70-2.38; p < 0.001), IL-21 (SMD 1.77, 95% CI 0.95-2.59; p < 0.001), and IL-23 (SMD 1.11, 95% CI 0.78-1.44; p < 0.001). The subgroup analysis showed higher levels of IL-17⁺ Th17 cells among peripheral blood mononuclear cells (PBMCs) and CD4⁺ T cells in patients with AS compared to HCs (SMD 2.26, 95% CI 1.58-2.94 [p < 0.001] and SMD 1.61, 95% CI 0.55-2.67 [p = 0.003], respectively). Patients with AS had higher levels of CD4⁺IL-17⁺IFN-γ^- Th17 in PBMCs and of CD4⁺CCR6⁺CCR4⁺Th17 in CD4⁺ T cells compared to HCs (SMD 1.85, 95% CI 1.06-2.64 [p < 0.001] and SMD 7.72, 95% CI 6.55-8.89 [p < 0.001], respectively). No significant differences were observed in the proportions of CD4⁺IL-17⁺IFN-γ^- Th17 in CD4⁺ T cells and CD4⁺CCR6⁺CCR4⁺ Th17 in PBMCs (SMD - 0.11, 95% CI - 0.61 to 0.38 [p = 0.650] and SMD 1.32, 95% CI - 0.54 to 3.19 [p = 0.165], respectively). In addition, compared to stable AS, the levels of Th17 cells and IL-17 and IL-23 were significantly higher in active AS (SMD 1.58, 95% CI 0.30-2.85 [p = 0.016], SMD 3.52, 95% CI 0.72-6.33 [p = 0.014], and SMD 5.10, 95% CI 1.83-8.36 [p = 0.002], respectively).

CONCLUSIONS

The levels of Th17 cells and serum IL-17, IL-21, and IL-23 were higher in patients with AS than in HCs and, compared with stable AS, they increased more significantly in active AS. These results suggest that Th17 cells and Th17-related cytokines play major roles in AS pathogenesis and are an important target for treatment.

Long-term outcomes of delayed percutaneous coronary intervention for patients with ST-segment elevation myocardial infarction: A propensity score-matched retrospective study

The best time window of percutaneous coronary intervention (PCI) is within 12 hours for ST-segment elevation myocardial infarction (STEMI). However, there is limited evidence about the proper time of PCI for delayed STEMI patients.From June 2014 to June 2015, a total of 268 patients receiving PCI with second-generation drug-eluting stent in a Chinese hospital after 3 days of STEMI onset were enrolled in this retrospective study, who were divided into the early group (3-14 days) and the late group (>14 days). A propensity score match was conducted to reduce the baseline difference. The primary endpoint of all-cause death and secondary endpoints of major adverse cardiac and cerebrovascular event (myocardial infarction [MI], stroke, emergent revascularization, and rehospitalization due to heart failure) were compared using survival analysis.At last, 182 cases were matched after propensity score match, with no statistical difference in baseline characteristics and PCI data. Kaplan-Meier survival curve demonstrated no difference in all-cause death of the 2 groups (P = .512). However, the early group presented a higher incidence of MI than the late group (P = .036). The multivariate Cox regression analysis also demonstrated that the early PCI was an independent risk factor for MI compared with late PCI (hazard ratio = 3.83, 95%CI [1.91-8.82], P = .001). There was no statistical difference in other major adverse cardiac and cerebrovascular event, including stroke, emergent revascularization, and rehospitalization due to heart failure.Using the 2nd drug-eluting stent, early PCI (3-14 days) and late PCI (>14 days) have comparable efficacy and outcomes. However, patients receiving early PCI are subjected to a relatively higher risk of recurrent MI.

Long non-coding RNA MEG3 inhibits M2 macrophage polarization by activating TRAF6 via microRNA-223 down-regulation in viral myocarditis

Viral myocarditis (VMC) commonly triggers heart failure, for which no specific treatments are available. This study aims to explore the specific role of long non‐coding RNA (lncRNA) maternally expressed 3 (MEG3) in VMC. A VMC mouse model was induced by Coxsackievirus B3 (CVB3). Then, MEG3 and TNF receptor‐associated factor 6 (TRAF6) were silenced and microRNA‐223 (miR‐223) was over‐expressed in the VMC mice, followed by determination of ventricular ejection fraction (LVEF) and left ventricular fractional shortening (LVFS). Dual‐luciferase reporter assay was introduced to test the interaction among MEG3, TRAF6 and miR‐223. Macrophages were isolated from cardiac tissues and bone marrow, and polarization of M1 or M2 macrophages was induced. Then, the expressions of components of NLRP3 inflammatory body (NLRP3, ASC, Caspase‐1), M1 markers (CD86, iNOS and TNF‐α) and M2 markers (CD206, Arginase‐1 and Fizz‐1) were measured following MEG3 silencing. In the VMC mouse model, MEG3 and TRAF6 levels were obviously increased, while miR‐223 expression was significantly reduced. Down‐regulation of MEG3 resulted in the inhibition of TRAF6 by promoting miR‐223. TRAF6 was negatively correlated with miR‐223, but positively correlated with MEG3 expression. Down‐regulations of MEG3 or TRAF6 or up‐regulation of miR‐223 was observed to increase mouse weight, survival rate, LVEF and LVFS, while inhibiting myocarditis and inflammation via the NF‐κB pathway inactivation in VMC mice. Down‐regulation of MEG3 decreased M1 macrophage polarization and elevated M2 macrophage polarization by up‐regulating miR‐223. Collectively, down‐regulation of MEG3 leads to the inhibition of inflammation and induces M2 macrophage polarization via miR‐223/TRAF6/NF‐κB axis, thus alleviating VMC.