M2 Macrophages Research Articles

Integrating machine learning and bioinformatics approaches for identifying novel diagnostic gene biomarkers in colorectal cancer.

This study aimed to identify diagnostic gene biomarkers for colorectal cancer (CRC) by analyzing differentially expressed genes (DEGs) in tumor and adjacent normal samples across five colon cancer gene-expression profiles (GSE10950, GSE25070, GSE41328, GSE74602, GSE142279) from the Gene Expression Omnibus (GEO) database. Intersecting identified DEGs with the module with the highest correlation to gene expression patterns of tumor samples in the gene co-expression network analysis revealed 283 overlapped genes. Centrality measures were calculated for these genes in the reconstructed STRING protein-protein interaction network. Applying LASSO logistic regression, eleven genes were ultimately recognized as candidate diagnostic genes. Among these genes, the area under the receiver operating characteristic curve (AUROC) values for nine genes (CDC25B, CDK4, IQGAP3, MMP1, MMP7, SLC7A5, TEAD4, TRIB3, and UHRF1) surpassed the threshold of 0.92 in both the training and validation sets. We evaluated the diagnostic performance of these genes with four machine learning algorithms: random forest (RF), support vector machines (SVM), artificial neural network (ANN), and gradient boosting machine (GBM). In the testing dataset (GSE21815 and GSE106582), the AUROC scores were greater than 0.95 for all of the machine learning algorithms, indicating the high diagnostic performance of the nine genes. Besides, these nine genes are also significantly correlated to twelve immune cells, namely Mast cells activated, Macrophages M0, M1, and M2, Neutrophils, T cells CD4 memory activated, T cells follicular helper, T cells CD8, T cells CD4 memory resting, B cells memory, Plasma cells, and Mast cells resting (P < 0.05). These results strongly suggest that all of the nine genes have the potential to serve as reliable diagnostic biomarkers for CRC.

Landscape of the immune infiltration and identification of molecular diagnostic markers associated with immune cells in patients with kidney transplantation

Rejection seriously affects the success of kidney transplantations. However, the molecular mechanisms underlying this rejection remain unclear. The GSE21374 and GSE36059 datasets were downloaded from the Gene Expression Omnibus (GEO) database. Next, the Cell-type Identification by Estimating Relative Subsets of RNA Transcripts (CIBERSORT) algorithm was used to infer the proportions of 22 immune cells. Moreover, infiltrating immune cell-related genes were identified using weighted gene co-expression network analysis (WGCNA), and enrichment analysis was conducted to observe their biological functions. Extreme Gradient Boosting (XGBoost) and Least Absolute Shrinkage and Selection Operator (LASSO) logistic regression algorithms were used to screen hub genes. Quantitative real-time PCR was conducted to verify the number of immune cells and hub gene expression levels. The rejection and non-rejection groups showed significantly different distributions (P < 0.05) of eight immune cells (B cell memory, Plasma cells, mast cells, follicular helper T cells, T CD8 cells, Macrophages M1, T Cells CD4 memory activated, and gamma delta T cells). Subsequently, CD8A, CRTAM, GBP2, WARS, and VAMP5 were screened as hub genes using the XGBoost and LASSO algorithms and could be used as diagnostic biomarkers. Finally, differential analysis and quantitative real-time PCR suggested that CD8A, CRTAM, GBP2, WARS, and VAMP5 were upregulated in rejection samples compared to non-rejection samples. The present study identified five key infiltrating immune cell-related genes (CD8A, CRTAM, GBP2,WARS, and VAMP5) involved in kidney transplant rejection, which may explain the molecular mechanism of rejection in kidney transplantation development.

Radical-Scavenging Violet Phosphorus Nanosheets for Attenuating Hyperinflammation and Promoting Infected Wound Healing.

Antibacterial therapy targeting the regulation of macrophage polarization may be a useful approach for normalizing the immune environment and accelerating wound healing. Inspired by black phosphorus-based nanoplatforms, more stable yet less-explored violet phosphorus nanosheets (VPNSs) are expected to provide a superior solution for effectively combating bacterial infections. In this study, an average thickness of 5-7nm VPNSs arefabricated through the liquid-phase exfoliation method to serve as an immunoregulatory dressing for the treatment of infected wounds. VPNSs attenuated excessive reactive oxygen species (ROS) and reduced the accumulation of proinflammatory M1 macrophages, showing notable antioxidant and anti-inflammatory properties. Comprehensive RNA sequencing further elucidated the potential immunoregulatory mechanisms of VPNSs, including modulation of the inflammatory response and enzyme regulator activity. Additionally, the inherent photothermal properties of the VPNSs contributed significantly to their antibacterial efficacy. When combined with near-infrared laser irradiation, VPNSs showed remarkable effectiveness in reducing infection-related complications and expediting wound healing in infected skin wound models. The rapid promotion of wound healing through ROS clearance, the regulation of macrophage polarization, and hyperthermia generation underscores the potential of the violet-phosphorus-based nanoplatforms as clinically viable agents for treating infected wounds. This study suggests that VPNSs are promising candidates for clinical anti-infective and anti-inflammatory applications.

TBK1 is involved in M-CSF-induced macrophage polarization through mediating the IRF5/IRF4 axis.

TANK binding kinase 1 (TBK1) is an important kinase that is involved in innate immunity and tumor development. Macrophage colony-stimulating factor (M-CSF) regulates the differentiation and function of macrophages towards the immunosuppressive M2 phenotype in the glioblastoma multiforme microenvironment. The role of TBK1 in macrophages, especially in regulating macrophage polarization in response to M-CSF stimulation, remains unclear. Here, we found high TBK1 expression in human glioma-infiltrating myeloid cells and that phosphorylated TBK1 was highly expressed in M-CSF-stimulated macrophages but not in granulocyte-macrophage CSF-induced macrophages (granulocyte-macrophage-CSF is involved in the polarization of M1 macrophages). Conditional deletion of TBK1 in myeloid cells induced M-CSF-stimulated bone marrow-derived macrophages to exhibit a proinflammatory M1-like phenotype with increased protein expression of CD86, interleukin-1β and tumor necrosis factor-α, as well as decreased expression of arginase 1. Mechanistically, TBK1 deletion or inhibition by amlexanox or GSK8612 reduced the expression of the transcription factor interferon-regulatory factor (IRF)4 and increased the level of IRF5 activation in macrophages stimulated with M-CSF, leading to an M1-like profile with highly proinflammatory factors. IRF5 deletion reversed the effect of TBK1 inhibition on M-CSF-mediated macrophage polarization. Our findings suggest that TBK1 contributes to the regulation of macrophage polarization in response to M-CSF stimulation partly through the IRF5/IRF4 axis.

Multifunctional carboxymethyl chitosan/oxidized carboxymethyl cellulose hydrogel loaded with ginsenoside Rg1 and polydopamine nanoparticles for infected diabetic wound healing

Besides bacterial infection, diabetic wounds are often accompanied by local inflammatory response, oxidative stress imbalances, and vascular formation disorders, which are the main reasons for long-term non-healing of diabetic wounds. In order to solve this problem, Ch-OCMC-PDA NPs-Rg1 self-healing hydrogel was constructed by Schiff base reaction. With the addition of PDA NPs and Rg1, Ch-OCMC-PDA NPs-Rg1 hydrogel showed excellent physical properties, like compressive strength of 142 kPa, swelling ratio of 148.91 %, and Rg1 carried in the hydrogel could achieve a slow release of 90.59 % within 48 h. What's more, PDA NPs endowed it with highly efficient photothermal antibacterial properties. In addition to excellent biocompatibility, Ch-OCMC-PDA NPs-Rg1 hydrogel could effectively clear intracellular reactive oxygen species, promote macrophages M2 transformation, and facilitate human umbilical vein endothelial cells migration and tube formation. In vivo experiments exhibited that Ch-OCMC-PDA NPs-Rg1 hydrogel could reduce wound inflammation, stimulate early angiogenesis, promote collagen deposition, and shorten the healing process of diabetic infected wounds, and the wound healing rate was significantly increased compared with other groups, reaching 98.41 ± 0.31 %. In summary, the multi-functional dynamic Ch-OCMC-PDA NPs-Rg1 hydrogel provides a new possibility for the treatment of diabetic infection wounds.

Role of cuproptosis in mediating the severity of experimental malaria-associated acute lung injury/acute respiratory distress syndrome

BackgroundMalaria-associated acute lung injury/acute respiratory distress syndrome (MA-ALI/ARDS) is a fatal complication of Plasmodium falciparum infection that is partially triggered by macrophage recruitment and polarization. As reported, copper exposure increases the risk of malaria infection, and copper accumulation-induced cuproptosis triggers M1 macrophage polarization. It is thus hypothesized that cuproptosis could act as a critical mediator in the pathogenesis of MA-ALI/ARDS, but its underlying mechanism remains unclear. The present study aimed to explore the role of cuproptosis in the severity of murine MA-ALI/ARDS.MethodsWe utilized an experimental model of MA-ALI/ARDS using female C57BL/6 mice with P. berghei ANKA infection, and treated these animals with the potent copper ion carrier disulfiram (DSF) or copper ion chelator tetrathiomolybdate (TTM). The RAW 264.7 macrophages, which were stimulated with infected red blood cells (iRBCs) in vitro, were also targeted with DSF-CuCl2 or TTM-CuCl2 to further investigate the underlying mechanism.ResultsOur findings showed a dramatic elevation in the amount of copper and the expression of SLC31A1 (a copper influx transporter) and FDX1 (a key positive regulator of cuproptosis) but displayed a notable reduction in the expression of ATP7A (a copper efflux transporter) in the lung tissue of experimental MA-ALI/ARDS mice. Compared to the P. berghei ANKA-infected control group, mice that were administered DSF exhibited a remarkable increase in parasitemia/lung parasite burden, total protein concentrations in bronchoalveolar lavage fluid (BALF), lung wet/dry weight ratio, vascular leakage, and pathological changes in lung tissue. Strikingly, the experimental MA-ALI/ARDS mice with DSF treatment also demonstrated dramatically elevated copper levels, expression of SLC31A1 and FDX1, numbers of CD86+, CD68+, SLC31A1+-CD68+, and FDX1+-CD68+ macrophages, and messenger RNA (mRNA) levels of pro-inflammatory cytokines (tumor necrosis factor [TNF-α] and inducible nitric oxide synthase [iNOS]) in lung tissue, but showed a remarkable decrease in body weight, survival time, expression of ATP7A, number of CD206+ macrophages, and mRNA levels of anti-inflammatory cytokines (transforming growth factor beta [TGF-β] and interleukin 10 [IL-10]). In contrast, TTM treatment reversed these changes in the infected mice. Similarly, the in vitro experiment showed a notable elevation in the mRNA levels of SLC31A1, FDX1, CD86, TNF-α, and iNOS in iRBC-stimulated RAW 264.7 cells targeted with DSF-CuCl2, but triggered a remarkable decline in the mRNA levels of ATP7A, CD206, TGF-β, and IL-10. In contrast, TTM-CuCl2 treatment also reversed these trends in the iRBC-stimulated RAW 264.7 cells.ConclusionsOur data demonstrate that the activation of cuproptosis with DSF aggravated the severity of MA-ALI/ARDS by partially inducing M1 polarization of pulmonary macrophages, while inhibition of cuproptosis with TTM contrarily ameliorated the severity of MA-ALI/ARDS by promoting macrophage M2 polarization. Our findings suggest that blockage of cuproptosis could be a potential therapeutic strategy for treatment of MA-ALI/ARDS.Graphical

IL-17RA/CTSK axis mediates H. pylori-induced castration-resistant prostate cancer growth.

In this investigation, we explored the molecular dynamics guiding the progression of castration-resistant prostate cancer (CRPC) influenced by Helicobacter pylori (H. pylori)-mediated M2 polarization of macrophages through the IL-17RA/CTSK/EMT axis. An 830-patient clinical trial categorized subjects into hormone-sensitive prostate cancer (HSPC) and CRPC groups. H. pylori infection, evaluated by ELISA, exhibited a higher incidence in CRPC patients, impacting overall survival (OS) and progression-free survival. In-depth in vitro and in vivo experiments, including 16S rDNA sequencing, immunohistochemical tests, and transcriptome analysis, unveiled that H. pylori promotes CRPC growth and metastasis by upregulating IL-17RA and CTSK, leading to enhanced EMT. Notably, M2 macrophages emerged as pivotal immune cells influencing CRPC progression. This study uncovers a novel pathway wherein H. pylori enrichment exacerbates CRPC by inducing macrophage M2 polarization, IL-17RA/CTSK expression, and EMT activation, shedding light on a previously unrecognized mechanism contributing to the growth and metastasis of CRPC.

Semaphorin 3D promotes pancreatic ductal adenocarcinoma progression and metastasis through macrophage reprogramming.

Axon guidance molecules are frequently altered in pancreatic ductal adenocarcinoma (PDA) and influence PDA progression. However, the molecular mechanism remained unclear. Using genetically engineered mouse models to examine semaphorin 3D (SEMA3D), we identified a dual role for tumor- and nerve-derived SEMA3D in the malignant transformation of pancreatic epithelial cells and invasive PDA development. Pancreatic-specific knockout of the SEMA3D gene from the KRASG12D and TP53R172H mutation knock-in, PDX1-Cre(KPC) mouse model demonstrated delayed tumor initiation, prolonged survival, absence of metastasis, and reduced M2 macrophage expression. Mechanistically, tumor- and nerve-derived SEMA3D indirectly reprograms macrophages through KRASMUT-dependent ARF6 signaling in PDA cells, resulting in increased lactate production, which is sensed by GPCR132 on macrophages to stimulate protumorigenic M2 polarization. Multiplex immunohistochemistry demonstrated increased M2-polarized macrophages proximal to nerves in SEMA3D-expressing human PDA tissue. This study suggests that altered SEMA3D expression leads to an acquisition of cancer-promoting functions, and nerve-derived SEMA3D is "hijacked" by PDA cells to support growth and metastasis in a KRASMUT-dependent manner.

Toll-like receptors ligand immunomodulators for the treatment congenital diaphragmatic hernia

BackgroundCongenital diaphragmatic hernia (CDH) is a rare disease that affects the development of the diaphragm, leading to abnormal lung development. Unfortunately, there is no established therapy for CDH. Retinoic acid pathways are implicated in the ethology of CDH and macrophages are known to play a role in repairing organ damage.MethodsWe have analyzed the effect of several Toll like receptor (TLR) ligands in the nitrofen-induced CDH model in pregnant rats widely used to study this disease and in the G2-GATA4Cre;Wt1fl/fl CDH genetic mice model. Morphometric and histological studies were carried out. Immune cell infiltration was assayed by immunochemistry and immunofluorescence and retinoic pathway gene expression analyzed in vivo and in vitro in macrophages.ResultsWe found that administering a single dose of atypical TLR2/4 ligands (CS1 or CS2), 3 days after nitrofen, cured diaphragmatic hernia in 73% of the fetuses and repaired the lesion with complete diaphragm closure being on the other hand nontoxic for the mothers or pups. Moreover, these immunomodulators also improved pulmonary hypoplasia and alveolar maturation and vessel hypertrophy, enhancing pulmonary maturity of fetuses. We also found that CS1 treatment rescued the CDH phenotype in the G2-GATA4Cre;Wt1fl/fl CDH genetic mice model. Only 1 out of 11 mutant embryos showed CDH after CS1 administration, whereas CDH prevalence was 70% in untreated mutant embryos. Mechanistically, CS1 stimulated the infiltration of repairing M2 macrophages (CD206+ and Arg1+) into the damaged diaphragm and reduced T cell infiltration. Additionally, those TLR ligands induced retinol pathway genes, including RBP1, RALDH2, RARα, and RARβ, in the affected lungs and the diaphragm and in macrophages in vitro.ConclusionsOur research has shown that TLR ligand immunomodulators that influence anti-inflammatory macrophage activation can be effective in treating CDH, being nontoxic for the mothers or pups suggesting that those TLR ligands are a promising solution for CDH leading to orphan drug designation for CS1. The immune system of the fetus would be responsible for repairing the damage and closure of the hernia in the diaphragm and enhanced proper lung development after CS1 treatment.

ERH is a prognostic biomarker associated with immune cell infiltration in lung cancer

Introduction The enhancer of rudimentary homolog (ERH) is significant in cancers, but its role in lung cancer is understudied. We divided lung cancer patients into high and low ERH expression groups based on tumor tissue levels. Methods Using the log-rank test, we analyzed the correlation between ERH expression and patient prognosis. The effects of high ERH expression on lung cancer cell proliferation, migration, and invasion were assessed using CCK8, EDU, transwell, and wound healing assays. Results ERH expression was significantly higher in cancerous versus normal lung tissue (p < 0.05), including lung adenocarcinoma (LUAD) and lung squamous cell carcinoma (LUSC). Patients with high ERH expression had worse overall survival (HR = 1.37, p = 2.5 × 10−7) and first progression survival (HR = 1.38, p = 0.00065) in lung cancer. However, while high ERH expression predicts an unfavorable prognosis in LUAD, it does not hold true for LUSC. Furthermore, knockdown of ERH inhibited lung cancer cell proliferation, migration, and invasion. ERH expression was linked to immune cell infiltration. High ERH expression in LUAD and LUSC samples correlated with higher CD8 T cell, T cells CD4 memory activated, and M1 macrophages abundance, while low ERH expression correlated with higher T cells CD4 memory resting abundance. Conclusion Upregulation of ERH in lung cancer tissue is associated with poor prognosis and immune cell infiltration.

Therapeutic potential of plasma-treated solutions in atopic dermatitis

Atopic Dermatitis (AD) is a prevalent inflammatory skin disease that is currently incurable. Plasma-treated solutions (PTS) (e.g., culture media, water, or normal saline, previously exposed to plasma) are being studied as novel therapy. Recently, PTS is gaining attention due to its advantages over non-thermal plasma (also known as cold atmospheric plasma). Thus, we explore the application of PTS in treating AD. In vivo experiments demonstrated that PTS significantly alleviated AD-like symptoms. It reduced mast cell and macrophage infiltration, decreased scratching times and serum IgE levels. These therapeutic effects of PTS on AD mice were associated with the activation of the antioxidant molecule Nrf2. In vitro experiments revealed that PTS could decrease ROS level and regulate cytokine expression (such as IL-6, IL-10, IL-13 and CCL17) in TNF-α/IFN-γ-stimulated keratinocytes and LPS-stimulated M1 macrophages. Additionally, PTS could upregulate the expression of antioxidant stress molecules such as Nrf2, HO-1, NQO1 and PPAR-γ in both cell types. Overall, PTS demonstrated potent therapeutic potential for AD without notable side effects. Our research provided a promising approach to AD treatment and may serve as a potential therapeutic strategy in other inflammatory skin diseases.

Preclinical studies of natural flavonoids in inflammatory bowel disease based on macrophages: a systematic review with meta-analysis and network pharmacology.

Flavonoid is a category of bioactive polyphenolic compounds that are extensively distributed in plants with specific pharmacological properties, such as anti-inflammatory and anti-oxidant. Importantly, natural flavonoids have shown the protected function on the dextran sulfate sodium (DSS)-induced colitis in animals and lipopolysaccharides (LPS)-induced inflammatory response in macrophages. The purpose of this systematic review is to explore the efficacy of natural flavonoids in animal models of IBD (inflammatory bowel disease) and potential mechanisms in macrophages by meta-analysis and network pharmacology in preclinical studies. Relevant foundation studies were searched from January 2010 to November 2023 in databases like PubMed, Elsevier ScienceDirect, and Web of Science. Then, OriginPro software was used to extract values from images, and the analysis was performed using Review Manager 5.3. The retrieved data was analyzed according to the fixed-effects model and random-effects model. Subsequently, heterogeneity was evaluated using the I2 statistics. Lastly, network pharmacology was applied to confirm mechanisms of natural flavonoids on IBD. According to the results of meta-analysis, we found the natural flavonoids exhibited powerful therapeutic effects against IBD, which not only reversed colonic shortness (WMD = 1.33, 95% CI (1.07, 1.59), P < 0.00001), but also reduced histological score (SMD = - 2.66, 95% CI (- 3.77, - 1.95), P < 0.00001) between natural flavonoid treatment groups compared with the experimental IBD model. Furthermore, treatment with natural flavonoids decreased the levels of tumor necrosis factor-α (TNF-α) in macrophages. Mechanistically, our summarized data substantiate that natural flavonoids alleviate LPS-induced M1 macrophage polarization, anti-oxidant, anti-inflammatory, maintain intestinal barrier, and inhibit the activation of the NLR family pyrin domain containing 3 (NLRP3) inflammasome in macrophages. Moreover, the results of network pharmacology also support this. This systematic review demonstrated the efficiency of natural flavonoids in treating IBD in preclinical research by meta-analysis and network pharmacology, which offered supporting evidence for clinical trial implementation. However, some limitations remain present, such as technique quality shortage, missed reports on account of negative results, failure to count sample size, and the risk of bias.

Attenuating mitochondrial dysfunction-derived reactive oxygen species and reducing inflammation: the potential of Daphnetin in the viral pneumonia crisis

Amidst the global burden of viral pneumonia, mitigating the excessive inflammatory response induced by viral pneumonia has emerged as a significant challenge. Pneumovirus infections can lead to the persistent activation of M1 macrophages, culminating in cytokine storms that exacerbate pulmonary inflammation and contribute to the development of pulmonary fibrosis. Mitochondria, beyond their role as cellular powerhouses, are pivotal in integrating inflammatory signals and regulating macrophage polarization. Mitochondrial damage in alveolar macrophages is postulated to trigger excessive release of reactive oxygen species (ROS), thereby amplifying macrophage-mediated inflammatory pathways. Recent investigations have highlighted the anti-inflammatory potential of Daphnetin, particularly in the context of cardiovascular and renal disorders. This review elucidates the mechanisms by which viral infection-induced mitochondrial damage promotes ROS generation, leading to the phenotypic shift of alveolar macrophages towards a pro-inflammatory state. Furthermore, we propose a mechanism whereby Daphnetin attenuates inflammatory signaling by inhibiting excessive release of mitochondrial ROS, thus offering mitochondrial protection. Daphnetin may represent a promising pharmacological intervention for viral pneumonia and could play a crucial role in addressing future pandemics.

Trophoblast cell-derived extracellular vesicles regulate the polarization of decidual macrophages by carrying miR-141-3p in the pathogenesis of preeclampsia

Dysregulation of macrophage polarization can prevent the invasion of trophoblast cells and further limit spiral artery remodeling in preeclampsia (PE). However, its mechanism is obscure. HTR8-/Svneo cells were cultured under normoxic or hypoxic conditions and extracellular vesicles (EVs) in the culture supernatants were extracted. Next, the cells were incubated with those EVs to investigate their effects on trophoblasts. A co-culture system consisting of HTR8-/Svneo cells and macrophages was used to reveal how the trophoblast-derived EVs affected the macrophage subtype. Finally, a PE mouse model and miR-141-3p knockout mice were used to verify the function of miR-141-3p in PE. Hypoxia induced abnormal increases in the levels of miR-141-3p in HTR8-/Svneo cells and EVs. EVs from hypoxia-treated HTR8-/Svneo cells could downregulate PTEN, a potential target of miR-141-3p, and inhibit trophoblast mitophagy and invasion. However, HTR8-/Svneo cells transfected with an miR-141-3p inhibitor could attenuate the influence of EVs. In an HTR8-/Svneo cell plus macrophage co-culture system, hypoxia-pretreated cells promoted the transformation of macrophages into the M1-phenotye, and HTR8-/Svneo invasion was inhibited by the macrophages. MiR-141 from EVs could target and downregulate dual specificity phosphatase 1 (DUSP1) expression in macrophages, induce formation of the M1 macrophage phenotype in THP-1 cells, downregulate DUSP1 expression, and upregulate TAB2/TAK1 signaling. These results were also demonstrated in normal pregnant mice and PE pregnant mice. A hypoxic environment could upregulate miR-141 expression in the EVs of HTR8-/Svneo cells, and THP-1-derived macrophages could uptake EVs releasing miR-141 to downregulate DUSP1 expression and induce the formation of M1 macrophages, which can lead to the development of PE.

Ninjurin1 deficiency differentially mitigates colorectal cancer induced by azoxymethane and dextran sulfate sodium in male and female mice.

This study investigated the role of Ninjurin1 (Ninj1), encoding a small transmembrane protein, in colitis-associated colon tumorigenesis in relation to sex hormones. Male and female wild-type (WT) and Ninj1 knockout (KO) mice were treated with azoxymethane (AOM) and dextran sulfate sodium (DSS), with or without testosterone propionate (TP). At week 2 (acute colitis stage), Ninj1 KO exhibited an alleviation in the colitis symptoms in both male and female mice. The M2 macrophage population increased and CD8+ T cell population decreased only in the female Ninj1 KO than in the female WT AOM/DSS group. In the female AOM/DSS group, TP treatment exacerbated colon shortening in the Ninj1 KO than in the WT. At week 13 (tumorigenesis stage), male Ninj1 KO mice had fewer tumors, but females showed similar tumors. In the WT AOM/DSS group, females had more M2 macrophages and fewer M1 macrophages than males, but this difference was absent in Ninj1 KO mice. In the Ninj1 KO versus WT group, the expression of pro-inflammatory mediators and Ho-1 and CD8+ T cell populations decreased in both female and male Ninj1 KO mice. In the WT group, M2 macrophage populations were increased by AOM/DSS treatment and decreased by TP treatment. However, neither treatment changed the cell populations in the Ninj1 KO group. These results suggest that Ninj1 is involved in colorectal cancer development in a testosterone-dependent manner, which was different in male and female. This highlights the importance of considering sex disparities in understanding Ninj1's role in cancer pathogenesis.

Pathomics models for CD40LG expression and prognosis prediction in glioblastoma

Glioblastoma (GBM) is the most prevalent primary malignant tumor of the nervous system. In this study, we utilized pathomics analysis to explore the expression of CD40LG and its predictive value for the prognosis of GBM patients. We analyzed the expression differences of CD40LG in GBM tissue and normal brain tissue, along with performing survival prognosis analysis. Additionally, histopathological sections of GBM were used to screen for pathological features. Subsequently, SVM and LR pathomics models were constructed, and the models’ performance was evaluated. The pathomics model was employed to predict CD40LG expression and patient prognosis. Furthermore, we investigated the potential molecular mechanisms through enrichment analysis, WGCNA analysis, immune correlation analysis, and immune checkpoint analysis. The expression level of CD40LG was significantly increased in GBM. Multivariate analysis demonstrated that high expression of CD40LG is a risk factor for overall survival (OS) in GBM patients. Five pathological features were identified, and SVM and LR pathomics models were constructed. Model evaluation showed promising predictive effects, with an AUC value of 0.779 for the SVM model, and the Hosmer–Lemeshow test confirmed the model’s prediction probability consistency (P > 0.05). The LR model achieved an AUC value of 0.785, and the Hosmer–Lemeshow test indicated good agreement between the LR model’s predicted probabilities and the true value (P > 0.05). Immune infiltration analysis revealed a significant correlation between the pathomics score (PS) and the degree of infiltration of activated DC cells, T cells CD4 naïve, Macrophages M2, Macrophages M1, and T cells CD4 memory resting. Our results demonstrate that the pathomics model exhibits predictability for CD40LG expression and GBM patient survival. These findings can be utilized to assist neurosurgeons in selecting optimal treatment strategies in clinical practice.

Designing injectable dermal matrix hydrogel combined with silver nanoparticles for methicillin-resistant Staphylococcus aureus infected wounds healing

Hydrogel-based delivery systems have now emerged as a pivotal platform for addressing chronic tissue defects, leveraging their innate capacity to suppress pathogenic infections and facilitate expedited tissue regeneration. In this work, an injectable hydrogel dressing, termed AgNPs-dermal matrix hydrogel (Ag@ADMH), has been designed to expedite the healing process of wounds afflicted with methicillin-resistant Staphylococcus aureus (MRSA), featuring sustained antibacterial efficacy. The synthesis of the hydrogel dressing entailed a self-assembly process of collagen fibers within an acellular dermal matrix to construct a three-dimensional scaffold, encapsulated with plant polyphenol-functionalized silver nanoparticles (AgNPs). The Ag@ADMH demonstrated exceptional biocompatibility, and enables a sustained release of AgNPs, ensuring prolonged antimicrobial activity. Moreover, the in vitro RT-qPCR analysis revealed that compared with ADMH, Ag@ADMH diminish the expression of iNOS while augmenting CD206 expression, thereby mitigating the inflammatory response and fostering wound healing. Especially, the Ag@ADMH facilitated a reduction in M1 macrophage polarization, as evidenced by a significant decrement in the M1 polarization trend and an enhanced M2/M1 ratio in dermal matrix hydrogels laden with AgNPs, corroborated by confocal microscopy and flow cytometry analyses of macrophage phenotypes. The in vivo assessments indicated that Ag@ADMH minimized fibrous capsule formation. In a full-thickness skin defect model of MRSA infection, the formulation significantly attenuated the inflammatory response by reducing MPO and CD68 expression levels, concurrently promoting collagen synthesis and CD34 expression, pivotal for vasculogenesis, thereby accelerating the resolution of MRSA-infected wounds. These attributes underscore the injectable extracellular matrix hydrogel as a formidable strategy for the remediation and regeneration of infected wounds.Graphical

Hypoxic glioma-derived exosomal miR-25-3p promotes macrophage M2 polarization by activating the PI3K-AKT-mTOR signaling pathway

BackgroundExosomes (EXO) play crucial roles in intercellular communication and glioma microenvironment modulation. Tumor-associated macrophages are more likely to become M2-like type macrophages in the immunosuppressive microenvironment. Here, we aimed to investigate the effects and molecular mechanisms of hypoxic glioma-derived exosomes mediated M2-like macrophage polarization.MethodsHighly expressed miRNAs in exosomes derived from glioma cells cultured under hypoxia condition compared to normoxic condition were identified through microRNA sequencing. The polarization status of macrophages was determined using qRT-PCR, Western blotting, flow cytometry, and immunohistochemistry. By using RNA-seq, we aimed to identify the downstream target genes regulated by miR-25-3p in macrophages and investigate the mechanistic pathways through which it exerts its effects. The proliferation and migration capabilities of glioma cells were assessed through EdU, Transwell assays, and in vivo experiments.ResultsWe found that miR-25-3p was upregulated in the exosomes derived from hypoxic glioma cells and can be transferred to the macrophage. In macrophages, miR-25-3p downregulates the expression of PHLPP2, thereby activating the PI3K-AKT-mTOR signaling pathway, ultimately leading to macrophage M2 polarization. As part of a feedback loop, M2-polarized macrophages can, in turn, promote malignant glioma progression.ConclusionOur study reveals that miR-25-3p from hypoxic glioma cells is delivered to macrophages via exosomes as a mediator, promoting M2 polarization of macrophages through the miR-25-3p/PHLPP2/PI3K-AKT signaling pathway. This study suggests that targeted interventions to modulate miR-25-3p expression, transmission, or inhibition of PI3K-AKT pathway activation can disrupt the immune-suppressive microenvironment, providing a novel approach for immunotherapy in gliomas.Graphical

SCG2 Mediates HNSCC Progression With CCL2/TGFβ1high M2 Macrophage Infiltration.

This study aims to unravel the mechanisms underlying M2 macrophage polarization in head and neck squamous cell carcinoma (HNSCC), and identify potential therapeutic targets. We conducted an integrated bioinformatic analysis using HNSCC bulk transcriptomes from TCGA and GEO databases to pinpoint critical factors influencing M2 macrophage polarization and tumor prognosis. The significance of these genes was validated in function analysis, single-cell transcriptome datasets, and invitro experiments. Their mechanisms in modulating M2 macrophage polarization were further explored by gene knockdown, cell coculture, and other assays for quantification. We identified a novel prognostic signature of five genes associated with M2 macrophage infiltration, in which SCG2 emerged as a pivotal factor in M2 macrophage polarization in HNSCC. High expression of SCG2 in tumor patients correlated with poorer prognoses, and knocking down SCG2 reduced the proliferation and migration of HNSCC cells, disrupting M2 macrophage polarization. Furthermore, interference of SCG2 resulted in a significant decrease in the secretion of pro-tumor cytokines such as CCL2 and TGFβ1. Our findings provide deeper insights into the pathogenesis of HNSCC and offer promising therapeutic targets for HNSCC, especially SCG2, to inhibit M2 macrophage polarization and modulate cytokine secretion.

Direct M2 macrophage co-culture overrides viscoelastic hydrogel mechanics to promote fibroblast activation.

Fibroblast activation drives fibrotic diseases such as pulmonary fibrosis. However, the complex interplay of how tissue mechanics and macrophage signals combine to influence fibroblast activation is not well understood. Here, we use hyaluronic acid hydrogels as a tunable cell culture system to mimic lung tissue stiffness and viscoelasticity. We applied this platform to investigate the influence of macrophage signaling on fibroblast activation. Fibroblasts cultured on stiff (50 kPa) hydrogels mimicking fibrotic tissue exhibit increased activation as measured by spreading as well as type I collagen and cadherin-11 expression compared to fibroblasts cultured on soft (1 kPa) viscoelastic hydrogels mimicking normal tissue. These trends were unchanged in fibroblasts cultured with macrophage-conditioned media. However, fibroblasts directly co-cultured with M2 macrophages show increased activation, even on soft viscoelastic hydrogels that normally suppress activation. Inhibition of interleukin 6 (IL6) signaling does not change activation in fibroblast-only cultures but ameliorates the pro-fibrotic effects of M2 macrophage co-culture. These results underscore the ability of direct M2 macrophage co-culture to override hydrogel viscoelasticity to promote fibroblast activation in an IL6-dependent manner. This work also highlights the utility of using hydrogels to deconstruct complex tissue microenvironments to better understand the interplay between microenvironmental mechanical and cellular cues.