B cell-derived IL-10 promotes the resolution of lipopolysaccharide-induced acute lung injury

Trichinella spiralis alleviates LPS-induced acute lung injury by modulating the protective Th2 immune response

Sepsis is a disorder of immune regulation caused by pathogenic microorganisms. A large number of inflammatory factors and inflammatory mediators are released, resulting in systemic inflammatory response disorder and acute lung injury (ALI). Helminths infection activate Th2 cytokines and immunomodulatory pathways, which have the function of anti-infection effector molecules. The early infection of Trichinella spiralis (T. spiralis) was mainly intestinal phase. In this study, we explored the effect of intestinal phase infection of T. spiralis on LPS-induced ALI. Compared with control mice, the serum and lung tissues of T. spiralis infected mice had a significant decrease of Th1 inflammatory cytokines, a significant increase of Th2 anti-inflammatory cytokines, and a significant decrease of inflammatory cell infiltration in lung tissue. These results suggest that T. spiralis during the intestinal phase can act on distal organs (lung) and reduce LPS-induced lung inflammation, providing evidence for a potential new pathway for immune-mediated disease in helminths and a possible role for intestinal worms in the gut-lung axis.

The cross-talk between B cells and macrophages

B cells and macrophages are significant immune cells that maintain the immune balance of the body. B cells are involved in humoral immunity, producing immune effects mainly by secreting antibodies. Macrophages participate in non-specific and specific immune responses. To gain a further understanding of macrophages and B cells, researchers have not only paid attention to the unidirectional influence between B cells and macrophages, but also have focused on the cross-talk between them, and the effect of this cross talk on diseases. Therefore, this review summarizes the influence of macrophages on B cells, the ways and mechanisms by which B cells affect macrophages, and their cross-talk, leading to a more comprehensive understanding of the mechanism of the interaction between macrophages and B cells.

Placental mesenchymal stem cells suppress inflammation and promote M2-like macrophage polarization through the IL-10/STAT3/NLRP3 axis in acute lung injury

INTRODUCTION

Acute lung injury (ALI) is a clinically severe respiratory disorder that currently lacks specific and effective pharmacotherapy. The imbalance of M1/M2 macrophage polarization is pivotal in the initiation and progression of ALI. Shifting macrophage polarization from the proinflammatory M1 phenotype to the anti-inflammatory M2 phenotype could be a potential therapeutic strategy. The intratracheal administration of placental mesenchymal stem cells (pMSCs) has emerged as a novel and effective treatment for ALI. This study aimed to investigate the role and downstream mechanisms of pMSCs in reprogramming macrophage polarization to exert anti-inflammatory effects in ALI.

METHODS

The study used lipopolysaccharide (LPS) to induce inflammation in both cell and rat models of ALI. Intratracheal administration of pMSCs was tested as a therapeutic intervention. An expression dataset for MSCs cultured with LPS-treated macrophages was collected from the Gene Expression Omnibus database to predict downstream regulatory mechanisms. Experimental validation was conducted through in vitro and in vivo assays to assess pMSCs effects on macrophage polarization and inflammation.

RESULTS

Both in vitro and in vivo experiments validated that pMSCs promoted M2 macrophage polarization and reduced the release of inflammatory factors. Further analyses revealed that pMSCs activated the signal transducer and activator of transcription (STAT)3 signaling pathway by secreting interleukin (IL)-10, leading to increased STAT3 phosphorylation and nuclear translocation. This activation inhibited NLRP3 inflammasome activation, promoting M2 macrophage polarization and suppressing the inflammatory response.

CONCLUSION

The study concluded that pMSCs alleviated lung injury in an LPS-induced ALI model by inhibiting M1 macrophage polarization and proinflammatory factor secretion, while promoting M2 macrophage polarization. This effect was mediated via the IL-10/STAT3/NLRP3 axis, presenting a novel therapeutic pathway for ALI treatment.

The iNKT cell ligand α-GalCer prevents murine septic shock by inducing IL10-producing iNKT and B cells

Introduction

α-galactosylceramide (α-GalCer), a prototypical agonist of invariant natural killer T (iNKT) cells, stimulates iNKT cells to produce various cytokines such as IFNγ and IL4. Moreover, repeated α-GalCer treatment can cause protective or pathogenic outcomes in various immune-mediated diseases. However, the precise role of α-GalCer-activated iNKT cells in sepsis development remains unclear. To address this issue, we employed a lipopolysaccharide (LPS)/D-galactosamine (D-GalN)-induced murine sepsis model and two alternative models.

Methods

Sepsis was induced in wild-type (WT) C57BL/6 (B6) mice by three methods (LPS/D-GalN, α-GalCer/D-GalN, and cecal slurry), and these mice were monitored for survival rates. WT B6 mice were intraperitoneally injected with α-GalCer or OCH (an IL4-biased α-GalCer analog) one week prior to the induction of sepsis. To investigate the effects of α-GalCer-mediated iNKT cell activation on sepsis development, immune responses were analyzed by flow cytometry using splenocytes and liver-infiltrating leukocytes. In addition, a STAT6 inhibitor (AS1517499) and an IL10 inhibitor (AS101) were employed to evaluate the involvement of IL4 or IL10 signaling. Furthermore, we performed B cell adoptive transfers to examine the contribution of α-GalCer-induced regulatory B (Breg) cell populations in sepsis protection.

Results

In vivo α-GalCer pretreatment polarized iNKT cells towards IL4- and IL10-producing phenotypes, significantly attenuating LPS/D-GalN-induced septic lethality in WT B6 mice. Furthermore, α-GalCer pretreatment reduced the infiltration of immune cells to the liver and attenuated pro-inflammatory cytokine production. Treatment with a STAT6 inhibitor was unable to modulate disease progression, indicating that IL4 signaling did not significantly affect iNKT cell-mediated protection against sepsis. This finding was confirmed by pretreatment with OCH, which did not alter sepsis outcomes. However, interestingly, prophylactic effects of α-GalCer on sepsis were significantly suppressed by treatment with an IL10 antagonist, suggesting induction of IL10-dependent anti-inflammatory responses. In addition to IL10-producing iNKT cells, IL10-producing B cell populations were significantly increased after α-GalCer pretreatment.

Conclusion

Overall, our results identify α-GalCer-mediated induction of IL10 by iNKT and B cells as a promising option for controlling the pathogenesis of postoperative sepsis.

Higher Levels of Cytokines in Patients with Chronic Limb-Threatening Ischemia

BACKGROUND

Inflammation is a key element in the initiation and progression of peripheral arterial disease (PAD). Understanding the impact of inflammatory molecules, as cytokines in PAD could help us to improve the prognosis of these patients. The main goal of this study was to compare the serum level of cytokines between patients with claudication to those with chronic limb-threatening ischemia (CLTI). The second objective was to evaluate the relationship between the levels of cytokines and death or amputation rate.

METHODS

An observational, single-center, and prospective study was conducted from January 2018 to July 2022. The study was approved by the ethical commission of the Local Hospital (75/2017). Patients with PAD, suggested by the clinical history and objective examination and confirmed with ankle-brachial index, attending vascular surgery consultations of the first author were included. The following exclusion criteria were applied: i) bedridden individuals or subjects who refused to participate in the protocol; ii) diseases responsible for body composition changes or proinflammatory state; iii) recent diet change, iv) active malignancy, v) autoimmune disease, vi) active infection, vii) chronic renal failure (glomerular filtration rate <30 mL/min/1.73 m2), or viii) heart failure in the past 3 months. This cohort was observed at admission, 3, 6, and 12 months. A panel of 27 cytokines was determined with ELISA, at baseline.

RESULTS

We included 119 subjects (mean age: 67.58 ± 9.60 years old; 79.80% males), 65 patients with claudication and 54 with CLTI. From the 27 cytokines analyzed, patients with CLTI, when compared to those with claudication, had a higher serum level of 11 cytokines: IL1ra, IL-6, IL-8, IL12 p70, G-CSF, IP-10, MCP-1, MIP-1α, PDGF-β, RANTES, and TNF-α. From the group of patients with CLTI those who underwent a major amputation had a higher serum level of FGF-basic [median = 49.04; interquartile range = 37.03-52.49; versus median = 33.04; interquartile range = 28.60-38.98; P = 0.001].

CONCLUSIONS

Patients with CLTI have higher serum level of inflammatory cytokines, which may have role in the prognosis of these patients.

Evaluation of the protective effect of Curcuma longa and PPARγ agonist, pioglitazone on paraquat-induced lung injury in rats

BACKGROUND

The inhalation of paraquat (PQ), one of the most widely used herbicides in the world, can result in lung injury. Curcuma longa (Cl) has long history in traditional and folk medicine for the treatment of a wide range of disorders including respiratory diseases.

AIM

The aim of the present work was to evaluate the preventive effect of Cl on inhaled PQ-induced lung injury in rats.

METHODS

Male Wistar rats were divided into 8 groups (n = 7), one group exposed to saline (control) and other groups exposed to PQ aerosol. Saline (PQ), Cl extract, (two doses), curcumin (Cu), pioglitazone (Pio), and the combination of Cl-L + Pio and dexamethasone (Dex) were administered during the exposure period to PQ. Total and differential white blood cell (WBC) counts, oxidant and antioxidant indicators in the bronchoalveolar lavage (BALF), interleukin (IL)-10, and tumor necrosis alpha (TNF-α) levels in the lung tissues, lung histologic lesions score, and air way responsiveness to methacholine were evaluated.

RESULTS

WBC counts (Total and differential), malondialdehyde level, tracheal responsiveness (TR), IL-10, TNF-α and histopathological changes of the lung were markedly elevated but total thiol content and the activities of catalase and superoxide dismutase were decreased in the BALF in the PQ group. Both doses of Cl, Cu, Pio, Cl-L + Pio, and Dex markedly improved all measured variables in comparison with the PQ group.

CONCLUSION

CI, Pio, and Cl-L + Pio improved PQ-induced lung inflammation and oxidative damage comparable with the effects of Dex.

STAT3-Mediated Ferroptosis is Involved in Sepsis-Associated Acute Respiratory Distress Syndrome

Sepsis-induced acute respiratory distress syndrome (ARDS) poses a grave danger to life, resulting from sepsis-induced multi-organ failure. Although ferroptosis, a form of iron-dependent lipid peroxidative cell death, has been associated with sepsis-induced ARDS, the specific mechanisms are not fully understood. In this study, we utilized WGCNA, PPI, friends analysis, and six machine learning techniques (Lasso, SVM, RFB, XGBoost, AdaBoost, and LightGBM) to pinpoint STAT3 as a potential diagnostic marker. A significant increase in monocyte and neutrophil levels was observed in patients with sepsis-induced ARDS, as revealed by immune infiltration analyses, when compared to controls. Moreover, there was a positive correlation between STAT3 expression and the level of infiltration. Single-cell analysis uncovered a notable disparity in B-cell expression between sepsis and sepsis-induced ARDS. Furthermore, in vitro experiments using LPS-treated human bronchial epithelial cells (BEAS-2B) and THP1 cells demonstrated a significant increase in STAT3 phosphorylation expression. Additionally, the inhibition of STAT3 phosphorylation by Stattic effectively prevented LPS-induced ferroptosis in both BEAS-2B and THP1 cells. This indicates that the activation of STAT3 phosphorylation promotes ferroptosis in human bronchial epithelial cells in response to LPS. In summary, this research has discovered and confirmed STAT3 as a potential biomarker for the diagnosis and treatment of sepsis-induced ARDS.

Deciphering the molecular nexus between Omicron infection and acute kidney injury: a bioinformatics approach

Background

The ongoing global health crisis of COVID-19, and particularly the challenges posed by recurrent infections of the Omicron variant, have significantly strained healthcare systems worldwide. There is a growing body of evidence indicating an increased susceptibility to Omicron infection in patients suffering from Acute Kidney Injury (AKI). However, the intricate molecular interplay between AKI and Omicron variant of COVID-19 remains largely enigmatic.

Methods

This study employed a comprehensive analysis of human RNA sequencing (RNA-seq) and microarray datasets to identify differentially expressed genes (DEGs) associated with Omicron infection in the context of AKI. We engaged in functional enrichment assessments, an examination of Protein-Protein Interaction (PPI) networks, and advanced network analysis to elucidate the cellular signaling pathways involved, identify critical hub genes, and determine the relevant controlling transcription factors and microRNAs. Additionally, we explored protein-drug interactions to highlight potential pharmacological interventions.

Results

Our investigation revealed significant DEGs and cellular signaling pathways implicated in both Omicron infection and AKI. We identified pivotal hub genes, including EIF2AK2, PLSCR1, GBP1, TNFSF10, C1QB, and BST2, and their associated regulatory transcription factors and microRNAs. Notably, in the murine AKI model, there was a marked reduction in EIF2AK2 expression, in contrast to significant elevations in PLSCR1, C1QB, and BST2. EIF2AK2 exhibited an inverse relationship with the primary AKI mediator, Kim-1, whereas PLSCR1 and C1QB demonstrated strong positive correlations with it. Moreover, we identified potential therapeutic agents such as Suloctidil, Apocarotenal, 3'-Azido-3'-deoxythymidine, among others. Our findings also highlighted a correlation between the identified hub genes and diseases like myocardial ischemia, schizophrenia, and liver cirrhosis. To further validate the credibility of our data, we employed an independent validation dataset to verify the hub genes. Notably, the expression patterns of PLSCR1, GBP1, BST2, and C1QB were consistent with our research findings, reaffirming the reliability of our results.

Conclusion

Our bioinformatics analysis has provided initial insights into the shared genetic landscape between Omicron COVID-19 infections and AKI, identifying potential therapeutic targets and drugs. This preliminary investigation lays the foundation for further research, with the hope of contributing to the development of innovative treatment strategies for these complex medical conditions.

Advances in nanomaterial-targeted treatment of acute lung injury after burns

Acute lung injury (ALI) is a common complication in patients with severe burns and has a complex pathogenesis and high morbidity and mortality rates. A variety of drugs have been identified in the clinic for the treatment of ALI, but they have toxic side effects caused by easy degradation in the body and distribution throughout the body. In recent years, as the understanding of the mechanism underlying ALI has improved, scholars have developed a variety of new nanomaterials that can be safely and effectively targeted for the treatment of ALI. Most of these methods involve nanomaterials such as lipids, organic polymers, peptides, extracellular vesicles or cell membranes, inorganic nanoparticles and other nanomaterials, which are targeted to reach lung tissues to perform their functions through active targeting or passive targeting, a process that involves a variety of cells or organelles. In this review, first, the mechanisms and pathophysiological features of ALI occurrence after burn injury are reviewed, potential therapeutic targets for ALI are summarized, existing nanomaterials for the targeted treatment of ALI are classified, and possible problems and challenges of nanomaterials in the targeted treatment of ALI are discussed to provide a reference for the development of nanomaterials for the targeted treatment of ALI.

Protective role of the HSP90 inhibitor, STA-9090, in lungs of SARS-CoV-2-infected Syrian golden hamsters

INTRODUCTION

The emergence of new SARS-CoV-2 variants, capable of escaping the humoral immunity acquired by the available vaccines, together with waning immunity and vaccine hesitancy, challenges the efficacy of the vaccination strategy in fighting COVID-19. Improved therapeutic strategies are urgently needed to better intervene particularly in severe cases of the disease. They should aim at controlling the hyperinflammatory state generated on infection, reducing lung tissue pathology and inhibiting viral replication. Previous research has pointed to a possible role for the chaperone HSP90 in SARS-CoV-2 replication and COVID-19 pathogenesis. Pharmacological intervention through HSP90 inhibitors was shown to be beneficial in the treatment of inflammatory diseases, infections and reducing replication of diverse viruses.

METHODS

In this study, we investigated the effects of the potent HSP90 inhibitor Ganetespib (STA-9090) in vitro on alveolar epithelial cells and alveolar macrophages to characterise its effects on cell activation and viral replication. Additionally, the Syrian hamster animal model was used to evaluate its efficacy in controlling systemic inflammation and viral burden after infection.

RESULTS

In vitro, STA-9090 reduced viral replication on alveolar epithelial cells in a dose-dependent manner and lowered significantly the expression of proinflammatory genes, in both alveolar epithelial cells and alveolar macrophages. In vivo, although no reduction in viral load was observed, administration of STA-9090 led to an overall improvement of the clinical condition of infected animals, with reduced oedema formation and lung tissue pathology.

CONCLUSION

Altogether, we show that HSP90 inhibition could serve as a potential treatment option for moderate and severe cases of COVID-19.