MicroRNA-451a and Th1/Th2 ratio inform inflammation, septic organ injury, and mortality risk in sepsis patients

Regulation of IL-17A-mediated hypersensitivity by extracellular vesicles and lipid nanoparticles carrying miR-451a

Extracellular vesicles (EVs), including exosomes, mediate intercellular communication by transporting functional molecules between donor cells and recipient cells, thereby regulating biological processes, such as immune responses. miR-451a, an immune regulatory microRNA, is highly abundant in circulating EVs; however, its precise physiological significance remains to be fully elucidated. Here, we demonstrate that miR-451a deficiency exacerbates delayed-type hypersensitivity (DTH) in mice. Notably, miR-451a knockout resulted in a significant increase in the number of interleukin (IL)-17A-expressing T helper 17 and γδ T cells infiltrating DTH-induced ear lesions. miR-451a deficiency also increased the number of γδ T cells in the secondary lymphoid tissues. Comprehensive analyses revealed that miR-451 deficiency promoted the expression of Rorc and γδ T cell-related genes following sensitization with allergens. Moreover, intravenous administration of wild-type EVs to miR-451a knockout mice increased cellular miR-451a levels in tissues and significantly attenuated the severity of DTH. Furthermore, synthetic lipid nanoparticles encapsulating miR-451a effectively mitigated DTH. Our findings indicate the importance of circulating miR-451a in the proliferation of γδ T cells and highlight the therapeutic potential of lipid nanoparticle-based microRNA delivery platforms for interventions in immune-related diseases.

Transcriptomic analysis of key genes and signaling pathways in sepsis-associated intestinal mucosal barrier damage

OBJECTIVES

The aim is to analyze differentially expressed genes (DEGs) in mice with sepsis-related intestinal mucosal barrier damage and to explore the diagnostic and protective mechanisms of this condition at the transcriptome level.

METHODS

Small intestinal tissues from healthy male C57BL/6J mice subjected to Cecal ligation and puncture (CLP) and sham operation were collected. High-throughput sequencing was performed using the paired-end sequencing mode of the Illumina HiSeq platform. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were conducted on the differentially expressed genes (DEGs). A protein-protein interaction (PPI) network was constructed using the STRING database, and hub genes were identified with Cytoscape. These hub genes were then validated using quantitative real-time polymerase chain reaction (RT-qPCR).

RESULTS

A total of 239 DEGs were identified, with 49 upregulated and 130 downregulated genes. KEGG enrichment analysis showed that these DEGs were primarily involved in cytokine-cytokine receptor interaction, Th1 and Th2 cell differentiation, viral protein interactions with cytokines and their receptors, and the IL-17 signaling pathway. The top 10 hub genes were selected using the cytoHubba plugin. Experimental validation confirmed that the expression levels of TBX21, CSF3, IL-6, CXCR3, and CXCL9 matched the sequencing results.

CONCLUSION

TBX21, CSF3, IL-6,CXCR3, and CXCL9 may be potential biological markers for the diagnosis and treatment the sepsis-associated intestinal mucosal barrier.

Extracellular Vesicles Derived From Lipopolysaccharide-Challenged Gingival Fibroblast Reveal Distinct miRNA Expression Patterns Associated With Reduced Cancer Survival

OBJECTIVES

Periodontitis is a prevalent inflammatory disease with established systemic implications. Extracellular vesicles (EVs) have emerged as key mediators of intercellular communication, potentially linking periodontitis to systemic diseases. However, the molecular cargo of EVs from inflamed periodontal cells remains poorly characterized. This study investigates the EV cargo of human gingival fibroblasts (hGF-hTERT) following lipopolysaccharide (LPS) stimulation and explores their potential role in cancer progression.

MATERIALS AND METHODS

EVs were isolated from LPS-treated and untreated fibroblasts via ultracentrifugation. Dynamic light scattering and scanning electron microscopy characterized EV size and morphology. RNA sequencing identified differentially expressed miRNAs, validated by qPCR. Functional pathway enrichment and in-silico analyses using The Cancer Genome Atlas (TCGA) were performed to assess EV-associated miRNA impact on tumorigenesis.

RESULTS

EV size and concentration remained unchanged after LPS stimulation. However, LPS-derived EVs exhibited a 2.6-fold increase in miRNA content, with three significantly upregulated miRNAs: miR-146a-5p, miR-486-5p, and miR-451a. Functional enrichment analysis revealed their involvement in inflammation, immune modulation, and cancer pathways. In vitro, LPS-derived EVs significantly enhanced prostate cancer (LnCap) cell proliferation. TCGA analysis linked the upregulated miRNAs to poor cancer prognosis.

CONCLUSIONS

LPS stimulation alters the miRNA cargo of gingival fibroblast-derived EVs, enhancing pathways associated with inflammation and cancer progression. These findings suggest a mechanistic role for periodontal EVs in systemic disease pathogenesis, warranting further investigation into their diagnostic and therapeutic potential.

Acupuncture Treats Sepsis through Immune Modulation and Organ Protection

Sepsis is a secondary condition resulting from severe systemic infections. It is a significant contributor to mortality in critically ill patients with rapid onset and severe symptoms. Acupuncture is a traditional Chinese medical treatment. Recent clinical studies have demonstrated that acupuncture, as an important synergistic therapy, has promising therapeutic effects in the treatment of sepsis. This paper reviews the mechanisms of immunomodulation and target organ protection associated with acupuncture and synergistic drug acupuncture in the treatment of sepsis. It also integrates existing studies to elucidate the modulation of the immune system and the protective effect of acupuncture on target organs.

Elucidating common pathogenic transcriptional networks in infective endocarditis and sepsis: integrated insights from biomarker discovery and single-cell RNA sequencing

Background

Infective Endocarditis (IE) and Sepsis are two closely related infectious diseases, yet their shared pathogenic mechanisms at the transcriptional level remain unclear. This research gap poses a barrier to the development of refined therapeutic strategies and drug innovation.

Methods

This study employed a collaborative approach using both microarray data and single-cell RNA sequencing (scRNA-seq) data to identify biomarkers for IE and Sepsis. It also offered an in-depth analysis of the roles and regulatory patterns of immune cells in these diseases.

Results

We successfully identified four key biomarkers correlated with IE and Sepsis, namely CD177, IRAK3, RNASE2, and S100A12. Further investigation revealed the central role of Th1 cells, B cells, T cells, and IL-10, among other immune cells and cytokines, in the pathogenesis of these conditions. Notably, the small molecule drug Matrine exhibited potential therapeutic effects by targeting IL-10. Additionally, we discovered two Sepsis subgroups with distinct inflammatory responses and therapeutic strategies, where CD177 demonstrated significant classification value. The reliability of CD177 as a biomarker was further validated through qRT-PCR experiments.

Conclusion

This research not only paves the way for early diagnosis and treatment of IE and Sepsis but also underscores the importance of identifying shared pathogenic mechanisms and novel therapeutic targets at the transcriptional level. Despite limitations in data volume and experimental validation, these preliminary findings add new perspectives to our understanding of these complex diseases.

Blocking Tim-3 enhances the anti-tumor immunity of STING agonist ADU-S100 by unleashing CD4+ T cells through regulating type 2 conventional dendritic cells

Rationale: An immunosuppressive tumor microenvironment (TME) is a major obstacle in tumor immunotherapy. Stimulator of interferon genes (STING) agonists trigger an inflammatory innate immune response to potentially overcome tumor immunosuppression. While STING agonists may hold promise as potential cancer therapy agents, tumor resistance to STING monotherapy has emerged in clinical trials, and the mechanisms remain unclear. Methods: The in vivo anti-tumor immunity of STING agonist ADU-S100 (S100), plus anti-T cell immunoglobulin and mucin-domain containing-3 antibody (αTim-3) were measured using murine tumor models. Tumor-specific T cell activation and alterations in the TME were detected using flow cytometry. The maturation and function of dendritic cells (DC) were also measured using flow cytometry, and the importance of CD4+ T cells in combination therapy was measured by blocking antibodies. Additionally, the effect of S100 on CD4+ T was verified via in vitro assays. Lastly, the impact of conventional dendritic cells (cDC) 2 with a high expression of Tim-3 on survival or therapeutic outcomes was further evaluated in human tumor samples. Results: S100 boosted CD8+ T by activating cDC1 but failed to initiate cDC2. Mechanistically, the administration of S100 results in an upregulation of Tim-3 expressed in cDC2 (Tim-3+cDC2) in both mice and humans, which is immunosuppressive. Tim-3+cDC2 restrained CD4+ T and attenuated the CD4+ T-driven anti-tumor response. Combining S100 with αTim-3 effectively promoted cDC2 maturation and antigen presentation, releasing CD4+ T cells, thus reducing tumor burden while prolonging survival. Furthermore, high percentages of Tim-3+cDC2 in the human TME predicted poor prognosis, whereas the abundance of Tim-3+cDC2 may act as a biomarker for CD4+ T quality and a contributing indicator for responsiveness to immunotherapy. Conclusion: This research demonstrated that blocking Tim-3 could enhance the anti-tumor immunity of STING agonist ADU-S100 by releasing CD4+ T cells through regulating cDC2. It also revealed an intrinsic barrier to ADU-S100 monotherapy, besides providing a combinatorial strategy for overcoming immunosuppression in tumors.