Efficacy and safety of inactivated SARS-CoV-2 vaccination in COVID-19-associated pneumonia among patients with rheumatic and musculoskeletal diseases: A real-world retrospective observational study.

OBJECTIVES: To identify the effectiveness and safety of inactivated SARS-CoV-2 vaccines in rheumatic and musculoskeletal diseases (RMDs) patients. METHODS: RMD patients with COVID-19 in Jiangsu Province were polled between December 8, 2022, and February 1, 2023. Information on demographics, disease characteristics, antirheumatic drug use, vaccination status and survival state were collected. COVID-19-associated pneumonia was the primary outcome. The effect of COVID-19 immunization on RMD patients was assessed using multivariate logistic regression, and the adverse events (AEs) following vaccination were evaluated. RESULTS: Among 592 RMD patients with COVID-19, 276 (46.6%) individuals experienced COVID-19-associated pneumonia, and 290 (49.0%) patients were injected with inactivated vaccines. In multivariate logistic regression analysis, vaccines reduced the incidence of COVID-19-associated pneumonia, and receiving booster vaccine was an independent protective factor for COVID-19-associated pneumonia in RMD patients (OR 0.64, 95% CI 0.41-0.98, p = .034). In particular, inactivated vaccines have a protective impact on RMD patients with a high risk of developing pneumonia, including those aged 45 years and older (OR 0.53, 95% CI 0.34-0.83), and who have lung involvement (OR 0.43, 95% CI 0.23-0.82). The total AEs rate of vaccines was 13.9% (40/290), only 11 (3.8%) experienced the recurrence or deterioration of RMDs, and no serious AEs occurred. CONCLUSION: Inactivated COVID-19 vaccines were safe and effective in reducing the risk of COVID-19-associated pneumonia of RMD patients in China.

Macrophages communicate with mesangial cells through the CXCL12/DPP4 axis in lupus nephritis pathogenesis.

Lupus nephritis (LN) occurs in 50% of cases of systemic lupus erythematosus (SLE) and is one of the most serious complications that can occur during lupus progression. Mesangial cells (MCs) are intrinsic cells in the kidney that can regulate capillary blood flow, phagocytose apoptotic cells, and secrete vasoactive substances and growth factors. Previous studies have shown that various types of inflammatory cells can activate MCs for hyperproliferation, leading to disruption of the filtration barrier and impairment of renal function in LN. Here, we characterized the heterogeneity of kidney cells of LN mice by single-nucleus RNA sequencing (snRNA-seq) and revealed the interaction between macrophages and MCs through the CXC motif chemokine ligand 12 (CXCL12)/dipeptidyl peptidase 4 (DPP4) axis. In culture, macrophages modulated the proliferation and migration of MCs through this ligand-receptor interaction. In LN mice, treatment with linagliptin, a DPP4 inhibitor, effectively inhibited MC proliferation and reduced urinary protein levels. Together, our findings indicated that targeting the CXCL12/DPP4 axis with linagliptin treatment may serve as a novel strategy for the treatment of LN via the CXCL12/DPP4 axis.

Rapidly progressive interstitial lung disease risk prediction in anti-MDA5 positive dermatomyositis: the CROSS model.

Background: The prognosis of anti-melanoma differentiation-associated gene 5 positive dermatomyositis (anti-MDA5+DM) is poor and heterogeneous. Rapidly progressive interstitial lung disease (RP-ILD) is these patients' leading cause of death. We sought to develop prediction models for RP-ILD risk in anti-MDA5+DM patients. Methods: Patients with anti-MDA5+DM were enrolled in two cohorts: 170 patients from the southern region of Jiangsu province (discovery cohort) and 85 patients from the northern region of Jiangsu province (validation cohort). Cox proportional hazards models were used to identify risk factors of RP-ILD. RP-ILD risk prediction models were developed and validated by testing every independent prognostic risk factor derived from the Cox model. Results: There are no significant differences in baseline clinical parameters and prognosis between discovery and validation cohorts. Among all 255 anti-MDA5+DM patients, with a median follow-up of 12 months, the incidence of RP-ILD was 36.86%. Using the discovery cohort, four variables were included in the final risk prediction model for RP-ILD: C-reactive protein (CRP) levels, anti-Ro52 antibody positivity, short disease duration, and male sex. A point scoring system was used to classify anti-MDA5+DM patients into moderate, high, and very high risk of RP-ILD. After one-year follow-up, the incidence of RP-ILD in the very high risk group was 71.3% and 85.71%, significantly higher than those in the high-risk group (35.19%, 41.69%) and moderate-risk group (9.54%, 6.67%) in both cohorts. Conclusions: The CROSS model is an easy-to-use prediction classification system for RP-ILD risk in anti-MDA5+DM patients. It has great application prospect in disease management.

Altered peripheral lymphocyte subsets in untreated systemic lupus erythematosus patients with infections

The leading cause of death in systemic lupus erythematosus (SLE) patients is infection. The objective of this study was to evaluate the distribution of lymphocyte subsets in untreated SLE patients with infections. This was a cross-sectional study. Data from January 2017 to May 2018 were collected. Flow cytometry was used to measure the peripheral lymphocyte subsets including CD3+T cells, CD4+T cells, CD8+T cells, CD19+B cells, CD3-CD16+CD56NK cells, and CD3+CD16+CD56NKT cells in 25 healthy controls and 52 treatment-naive SLE patients, among whom 13 were complicated with infections. Association between the lymphocyte subsets and infections was further analyzed. SLE patients with infections (n=13) showed a significantly higher incidence rate of fever (84.6 vs 28.2%) and serositis (84.6 vs 23.1%), increased level of erythrocyte sedimentation rate (60.5±30.1 vs 37.4±27.1 mm/h), serum C-reactive protein (CRP) (102.7±94.9 vs 9.4±14.9 mg/L), procalcitonin (PCT) (1.07±0.08 vs 0.16±0.13 μg/L), and lower blood hemoglobin (Hb) (93.0±20.5 vs 110.4±16.0 g/L) level compared with non-infection patients (n=39) (all P<0.05). In comparison with non-infectious SLE patients (387.9±261.6/μL), CD4+T cells count decreased significantly in infectious SLE patients (217.8±150.4/μL) (P<0.05), and it was negatively correlated with infection-related indicators including PCT (r=−0.573, P=0.041) and CRP (r=−0.596, P=0.032) levels. Our findings suggested that abnormalities of peripheral lymphocyte subsets were related to the immune disorder of lupus itself, regardless of immunosuppressive treatment. Monitoring lymphocyte subsets, especially CD4+T cells, may be helpful for identifying the presence of infection in SLE patients.