Dampened Inflammation and Improved Survival After CXCL5 Administration in Murine Lupus via Myeloid and Neutrophil Pathways

Proinflammatory Cytokine Profiles in Menière's Disease and Vestibular Migraine

OBJECTIVE

To evaluate the levels of inflammatory cytokines and symptom survey scores in patients diagnosed with Menière's disease or vestibular migraine from a single center by a single neurotologist compared to control subjects with no history of dizziness or migraine.

STUDY DESIGN

Cross-sectional pilot study.

SETTING

Single-center tertiary referral center in Charleston, SC.

PATIENTS

Patients were recruited from the neurotology clinic at a tertiary referral center. Patients with definite Menière's disease or definite vestibular migraine as defined by the Barany consensus criteria were eligible. Control subjects presented to clinic without dizziness, vertigo, fluctuating hearing loss, or a history of migraine.

MAIN OUTCOME MEASURES

Questionnaire scores include DHI, SF-20, CFQ, PHQ-9, PSWQ, GAD-7, NVI, DCS, VM-PATHI, and MD-POSI. Circulating and in vitro levels of cytokines include ENA-78, GROα, IFN-α2a, IFN-γ, IL-10, IL-1α, IL-1β, IL-1RA, IL-2, IL-4, IL-5, IL-6, IL-8, MCP-1, MCP-2, MDC, MIP-1α, MIP-1β, and TNF-α. Cytokine levels were compared with effect size analysis.

RESULTS

There were 20 Menière's disease, 20 vestibular migraine, and 10 control patients enrolled in this study. Episode frequencies ranged from three per week to two to five per year in the MD group and daily to 1 every 2 to 3 months in the VM group. When patient-derived PBMC samples were compared to vestibular migraine, TNF-α ( d = -0.427 [-0.879, 0.025]) and IFN-γ ( d = -0.818 [-1.313, -0.323]) were found to be higher in Menière's disease, whereas ENA-78 ( d = -0.652 [-1.361, 0.056]) was found to be lower. No differences were found when cytokines were measured following stimulation with LPS.

CONCLUSIONS

This pilot study suggests Menière's disease patients may have higher levels of TNF-α and IFN-γ and lower levels of ENA-78 than vestibular migraine patients when measured following in vitro release from patient-derived PBMC. Increased sample size, optimized blood draw timing, and more specific PBMC stimulation may help us further elucidate inflammatory pathways implicated in these disorders.

The role of neutrophil extracellular traps in inflammatory rheumatic diseases

PURPOSE OF REVIEW

Dysregulation in neutrophil extracellular trap (NET) formation and degradation has been reported in several inflammatory rheumatic diseases. This review summarizes the recent advances in the understanding the role of NETs in the context of inflammatory rheumatic diseases.

RECENT FINDINGS

NET formation is enhanced in peripheral blood of patients with large vessel vasculitis and polymyalgia rheumatica. NETs are detected in affected organs in autoimmune conditions, and they might play pathological roles in tissues. Several understudied medications and supplements suppress NET formation and ameliorate animal models of inflammatory rheumatic diseases. NETs and anti-NET antibodies have potential utility as disease biomarkers.

SUMMARY

Growing evidence has suggested the contribution of NET dysregulation to the pathogenesis of several inflammatory rheumatic diseases. Further research is warranted in regard to clinical impact of modulating aberrant NET formation and clearance in inflammatory rheumatic diseases.

Impact of Gut Microbiota and Inflammatory Cytokines on Immune Thrombocytopenia

Immune thrombocytopenic purpura (ITP) is an autoimmune disorder, and recent research suggests that gut microbiota and inflammatory cytokines may play a significant role in its pathogenesis. However, the specific effects of these factors on ITP and their relationships remain unclear. We conducted a two-step, two-sample Mendelian randomization study using an inverse variance-weighted approach to investigate the causal role of the gut microbiota in ITP and the mediating effect of inflammatory cytokines on their association. The results showed that among the 473 gut microbiota species, 11 were positively associated and 12 were negatively associated with the risk of ITP. Among the 91 screened inflammatory cytokines, five (CXCL10, CXCL5, IL-12RA, TRAIL, and VEGF-A) were found to have a causal relationship with ITP. Mediation analysis revealed that the gut microbiota UBA1066 promoted the occurrence of ITP through CXCL10 mediation, with a mediation effect of 0.118932 (95% CI: 0.049471-0.188393) accounting for 9.95% of the total effect. Gut microbiota Treponema promoted ITP through VEGF-A mediation, with a mediation effect of 0.045873 (95% CI: 0.01456-0.07718) accounting for 4.28% of the total effect. Gut microbiota Haloplasma promoted the occurrence of ITP via CXCL5. The mediating effect of CXCL5 was 0.038409 (95% CI = 0.00107718-0.07575082), with a mediating ratio of 16.79%. This study revealed a causal relationship between gut microbiota composition and ITP risk, highlighting three inflammatory cytokines as potential causal mediators of this relationship. These findings provide potential targets and biomarkers for the prevention and treatment of ITP with significant clinical implications.

Serum levels of CXCL5 are decreased and correlate with circulating platelet counts in systemic lupus erythematosus

OBJECTIVE

To identify disease-specific serum chemokine profiles and potential anti-inflammatory chemokines in three rheumatic diseases.

METHODS

The discovery cohort included 18 patients with rheumatoid arthritis (RA), 20 patients with primary Sjögren's syndrome (pSS), 24 patients with systemic lupus erythematosus (SLE) and 28 healthy subjects. Findings from the discovery cohort were validated in two replication cohorts, consisting of 23 patients with SLE matched with 23 healthy subjects and 62 patients with SLE, 16 patients with ANCA-associated vasculitis (AAV), and 32 healthy controls, respectively. Serum levels of chemokines were determined using multiplex assay or ELISA.

RESULTS

In the discovery cohort, serum levels of multiple chemokines were increased in one or more diseases in comparison to healthy subjects, including CCL2, CCL20, CXCL9, CXCL10, and CXCL11 in SLE, CCL2, CCL4, and CXCL11 in pSS, and CCL2, CCL4, and CXCL9 in RA. Notably, serum levels of CCL3 (p = .0003) and CXCL5 (p = .0003) were decreased in SLE. The SLE-specific decrease in CXCL5 serum levels was confirmed in the two replication cohorts, with p = .0034 and p = .0006, respectively. Moreover, a positive correlation between serum levels of CXCL5 and circulating platelet counts (R = .71, p = .00018) in SLE observed in the discovery cohort was confirmed in both replication cohorts (R = .52, p = .011 and R = .49, p = .00005, respectively).

CONCLUSION

In the present study, we demonstrate that serum levels of CXCL5 are decreased in patients with SLE and positively correlated with circulating platelet count. These findings suggest that platelet-associated CXCL5 is presumably involved in the development of SLE.

Modified Bushen Yiqi formula enhances antitumor immunity by reducing the chemotactic recruitment of M2-TAMs and PMN-MDSCs in Lewis lung cancer-bearing mice

ETHNOPHARMACOLOGICAL RELEVANCE

Modified Bushen Yiqi formula (MBYF) has shown efficacy as an herbal combination therapy with anti-PD-1 for lung cancer patients. However, the underlying mechanisms of its antitumor effects in lung cancer remain unclear.

AIM OF THE STUDY

This study aims to observe the antitumor effect of MBYF and explore its synergistic mechanism in combination with anti-PD-1 based on the tumor immune microenvironment.

MATERIALS AND METHODS

The antitumor effect of MBYF was assessed in Lewis Lung Cancer (LLC)-bearing mice by evaluating tumor volume, weight, and histology in five groups (model control, MBYF 8.125 g/kg, MBYF 16.25 g/kg, MBYF 32.50 g/kg, anti-PD-1). Mechanisms were analyzed using pharmacology network and tumor RNA-sequencing. Tumor-infiltrating immune cells were measured by flow cytometry and immunohistochemistry. Targets and pathways were validated through qRT-PCR, immuno-histochemistry, and western blotting. The synergistic effect of MBYF in combination with anti-PD-1 was validated in three groups (model control, anti-PD-1, anti-PD-1+MBYF 16.25 g/kg).

RESULTS

MBYF inhibited tumor growth and proliferation and demonstrated safety for the heart, liver, and kidney. Mechanistically, MBYF downregulated tumor proliferation by suppressing the expression of CCND1, CTNNB1, EGFR, and the PI3K-AKT/STAT3/ERK pathway. Furthermore, MBYF may upregulated the antitumor immunity (CD4+T cells, active CD8+ T cells, and NK cells) by reducing the infiltration of M2-TAMs and PMN-MDSCs. MBYF may inhibit the recruitment of M2-TAMs by downregulating the CCR5-CCLs axis and PMN-MDSCs by the CXCR2-CXCLs axis. In vivo study confirmed that MBYF enhanced the antitumor effect of anti-PD-1 therapy.

CONCLUSION

Modified Bushen Yiqi formula enhances antitumor immunity in the treatment of lung cancer by reducing the chemotactic recruitment of M2-TAMs and PMN-MDSCs, suggesting its potential as an adjunct therapy to enhance anti-PD-1 responses and improve treatment outcomes. Further research and clinical studies are needed to validate and expand upon these promising findings.

Effect of BAFF blockade on the B cell receptor repertoire and transcriptome in a mouse model of systemic lupus erythematosus

Introduction

Systemic lupus erythematosus (SLE) is a heterogeneous autoimmune disease. Anti-B-cell-activating factor (BAFF) therapy effectively depletes B cells and reduces SLE disease activity. This research aimed to evaluate the effect of BAFF blockade on B cell receptor (BCR) repertoire and gene expression.

Methods

Through next-generation sequencing, we analyzed gene expression and BCR repertoire in MRL/lpr mice that received long-term anti-BAFF therapy. Based on gene expression profiles, we predicted the relative proportion of immune cells using ImmuCellAI-mouse, validating our predictions via flow cytometry and FluoroSpot.

Results

The loss of BCR repertoire diversity and richness, along with increased clonality and differential frequency distribution of the immunoglobulin heavy chain variable (IGHV) segment gene usage, were observed in BAFF-blockade mice. Meanwhile, the distribution of complementarity-determining region 3 (CDR3) length and CDR3 amino acid usage remained unaffected. BAFF blockade resulted in extensive changes in gene expression, particularly that of genes related to B cells and immunoglobulins. Besides, the tumor necrosis factor (TNF)-α responses and interferon (IFN)-α/γ were downregulated, consistent with the decrease in IFN-γ and TNF-α serum levels following anti-BAFF therapy. In addition, BAFF blockade significantly reduced B cell subpopulations and plasmacytoid dendritic cells, and caused the depletion of antibody-secreting cells.

Discussion

Our comparative BCR repertoire and transcriptome analyses of MRL/lpr mice subjected to BAFF blockade provide innovative insights into the molecular pathophysiology of SLE.

Similarities and differences between myocarditis following COVID-19 mRNA vaccine and multiple inflammatory syndrome with cardiac involvement in children

Despite the multiple benefits of vaccination, cardiac adverse Events Following COVID-19 Immunization (c-AEFI) have been reported. These events as well as the severe cardiac involvement reported in Multisystem inflammatory syndrome in children (MIS-C) appear more frequent in young adult males. Herein, we firstly report on the inflammatory profiles of patients experiencing c-AEFI in comparison with age, pubertal age and gender matched MIS-C with cardiac involvement. Proteins related to systemic inflammation were found higher in MIS-C compared to c-AEFI, whereas a higher level in proteins related to myocardial injury was found in c-AEFI. In addition, higher levels of DHEAS, DHEA, and cortisone were found in c-AEFI which persisted at follow-up. No anti-heart muscle and anti-endothelial cell antibodies have been detected. Overall current comparative data showed a distinct inflammatory and androgens profile in c-AEFI patients which results to be well restricted on heart and to persist months after the acute event.

Intraperitoneally Delivered Umbilical Cord Lining Mesenchymal Stromal Cells Improve Survival and Kidney Function in Murine Lupus via Myeloid Pathway Targeting

To determine the therapeutic efficacy of human umbilical cord lining mesenchymal stromal cells (CL-MSCs) (US Patent number 9,737,568) in lupus-prone MRL/lpr (Fas^lpr) mice and elucidate its working mechanisms. A total of 4 doses of (20-25) × 10⁶ cells/kg of CL-MSCs was given to 16-week-old female Fas^lpr mice by intraperitoneal injection. Three subsequent doses were given on 17 weeks, 18 weeks, and 22 weeks, respectively. Six-week-old Fas^lpr mice were used as disease pre-onset controls. Mice were monitored for 10 weeks. Mouse kidney function was evaluated by examining complement component 3 (C3) deposition, urinary albumin-to-creatinine ratio (ACR), and lupus nephritis (LN) activity and chronicity. Working mechanisms were elucidated by flow cytometry, Luminex/ELISA (detection of anti-dsDNA and isotype antibodies), and RNA sequencing. CL-MSCs improved mice survival and kidney function by reducing LN activity and chronicity and lymphocyte infiltration over 10 weeks. CL-MSCs also reduced urinary ACR, renal complement C3 deposition, anti-dsDNA, and isotype antibodies that include IgA, IgG1, IgG2a, IgG2b, and IgM. Immune and cytokine profiling demonstrated that CL-MSCs dampened inflammation by suppressing splenic neutrophils and monocytes/macrophages, reducing plasma IL-6, IL-12, and CXCL1 and stabilizing plasma interferon-γ and TNF-α. RNA sequencing further showed that CL-MSCs mediated immunomodulation via concerted action of pro-proinflammatory cytokine-induced chemokines and production of nitric oxide in macrophages. CL-MSCs may provide a novel myeloid (neutrophils and monocytes/macrophages)-targeting therapy for SLE.