Mechanical stretch is utilized in the process of tissue expansion to promote skin regeneration, which is crucial for wound healing and organ reconstruction purposes. Enlarged dermal area is one of the significant histological characteristics of the expanded skin. However, the underlying biological processes and molecular pathways associated with dermal regeneration triggered by mechanical stretch are still not well understood.

Twelve male Sprague-Dawley (SD) rats were divided into the expansion group and sham group randomly. Upon creating a rat scalp expansion model, the dermis was isolated from the full-thickness skin in both experimental groups for RNA sequencing. This process led to the identification of differentially expressed genes (DEGs). Subsequently, we conducted Gene Ontology (GO) analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, and Gene Set Enrichment Analysis (GSEA) to identify the essential biological processes associated with dermal regeneration induced by mechanical stretch, leveraging data from the DEGs. A network of protein-protein interactions (PPI) was built to detect the critical modules and central genes. The expression levels of these hub genes were evaluated using quantitative real-time polymerase chain reaction (qPCR).

Increased expanded skin area and dermal thinning which represent the typical changes of expanded skin were observed in the expansion group. A total of 782 DEGs were identified in the expansion group relative to the sham group. The DEGs were associated with several biological processes, including the organization of the extracellular matrix, the enhancement of macrophage activation, and the promotion of angiogenesis, among others. Cell components encompassing Toll-like receptor 2-Toll-like receptor 6 protein complex, interstitial matrix, extracellular matrix (ECM), and collagen trimer were discovered. Molecular function categories including integrin binding, insulin-like growth factor binding, and fatty acid elongase activity were involved. The KEGG pathway analysis demonstrated the significant enrichment of pathways including the PI3K-Akt signaling pathway, fatty acid metabolism, and extracellular matrix-receptor interactions. GSEA results displayed that mechanical stretch correlated with the regulation of cell activation processes, cytokine-mediated signaling pathways, and immune system processes. PPI network resulted in the identification of 598 nodes along with a total of 5,304 interaction pairs between proteins. And ten hub genes containing Ccl2, Cxcl10, Fasn, Itgad, Cd163, Mmp9, Cd36, Tlr2, Igf1, and Wnt2 were identified by bioinformatics analysis and validated by qPCR.

This in vivo study for the first time revealed the DEGs related to mechanical stretch stimulated dermal regeneration and identified the involved pathways and hub genes correlated with macrophage recruitment and polarization, fibroblast proliferation and ECM production and angiogenesis, which may benefit further studies aimed at developing therapeutic strategies for facilitating expanded skin regeneration.

Glutaminyl-peptide cyclotransferase-like protein (QPCTL) is a newly discovered enzyme that has sparked interest owing to its possible role in cancer genesis and progression. Initially discovered as a post-translational modification regulator of protein maturation, QPCTL has emerged as a key participant in cancer biology. Recent research has linked QPCTL to numerous essential cancer-related processes, including cell proliferation, migration, invasion, and apoptosis. Furthermore, QPCTL expression changes have been seen in a variety of cancer types, underlining its potential as a diagnostic and prognostic marker. The molecular mechanisms behind QPCTL's participation in cancer will be examined in this review. We investigate its involvement in the control of signaling pathways and the modification of cellular activities that are important in cancer. We also examine the clinical importance of QPCTL, including as its relationship with tumor development, metastasis, and response to treatment. We also discuss the possible therapeutic implications of targeting QPCTL in cancer therapy. QPCTL is a prospective target for the development of innovative anticancer treatments due to its participation in several cancer-associated pathways.

The predominant component of kidney stone is calcium oxalate monohydrate (COM), a fact widely acknowledged. Although rodent models are frequently used to induce calcium oxalate (CaOx) crystallization, further exploration of Randall's plaques (RPs) in these models is still needed. We first selected the GSE89028 and GSE75542 datasets from the Gene Expression Omnibus (GEO) database to identify commonly differentially expressed genes (co-DEGs). Based on co-DEGs, we conducted Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses to identify significantly enriched pathways. Additionally, we performed Gene Set Enrichment Analysis (GSEA) to validate the enriched pathways. In order to identify hub genes, we established a network of protein-protein interactions (PPI). Finally, we conducted real-time PCR and Western blot to validate the findings from the bioinformatics analysis. We selected 28 co-DEGs from two datasets. The enrichment analysis using GO, KEGG, and GSEA revealed significant enrichment of chemokine-related signaling pathways. The histogram analysis showed that three chemokine factor-related genes were involved in multiple pathways. We used Cytohubba to confirm the presence of three hub genes. Subsequently, analysis of external datasets and quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot demonstrated significant upregulation of CCL2, CXCL1, and CXCL2 in HK-2 cells following CaOx treatment compared to the control group (p < 0.05). Our study demonstrated that upon stimulation by CaOx, renal tubular epithelial cells release chemokines, including CCL2, CXCL1, and CXCL2. This release of chemokines is accompanied by the activation of signaling pathways such as TNF and IL-17. These findings may provide new directions for future research on Kidney Stone Disease.

Porcine reproductive and respiratory syndrome virus (PRRSV) causes significant economic losses in the global swine industry due to its high genetic diversity and different virulence levels, which complicate disease management and vaccine development. This study evaluated longitudinal changes in the immune cell composition of bronchoalveolar lavage fluid and the clinical outcomes across PRRSV strains with varying virulence, using techniques including single-cell transcriptomics. In highly virulent infection, faster viral replication results in an earlier peak lung-damage time point, marked by significant interstitial pneumonia, a significant decrease in macrophages, and an influx of lymphocytes. Viral tracking reveals less than 5% of macrophages are directly infected, and further analysis indicates bystander cell death, likely regulated by exosomal microRNAs as a significant factor. In contrast, the peak intermediate infection shows a delayed lung-damage time point with fewer cell population modifications. Furthermore, anti-inflammatory M2-like macrophages (SPP1-CXCL14high) are identified and their counts increase during the peak lung-damage time point, likely contributing to local defense and lung recovery, which is not observed in high virulent infection. These findings provide a comprehensive description of the immune cellular landscape and differential PRRSV virulence mechanisms, which will help build new hypotheses to understand PRRSV pathogenesis and other respiratory infections.

Background/Objectives: The stimulator of interferon genes (STING) is currently accepted as a relevant target for anti-cancer therapies. Besides encouraging results showing STING agonist-induced tumor growth inhibition, in some types of tumors the effect is less prominent. We hypothesized that higher STING levels in cancer cells and the possibility of its activation determine a greater anti-cancer response. As the local administration of STING agonists induces a systemic reaction, we emphasized the importance of host tumor-induced hematological disruption in the efficiency of the therapeutic response. Methods: We investigated the response to STING stimulation in murine cancer cell lines-melanoma (B16-F10) and breast carcinoma (4T1)-and murine normal cell lines: fibroblast cells (NIH/3T3), endothelial cells (H5V), and macrophages (J774A.1). We assessed STING agonist-induced tumor growth inhibition and the therapy's impact on the hematological system parameters and systemic cytokine release. Results: Our results underlined the improved therapeutic effect of STING activation in melanoma (B16-F10) over breast carcinoma (4T1) tumors. The outcomes reflected a high dysregulation of the hematological system in mice with developed 4T1 tumors, which may support persistent inflammation and impede STING-induced therapeutic effects. Moreover, among typical cytokines produced following STING activation, CCL2 fold change was the one that increased the most in the serum of B16-F10-bearing mice and differentiated the observed response to the STING agonist between investigated tumor models. Conclusions: The current study provides new evidence of the different responses to STING activation among two poorly immunogenic tumor models. The high abundance of STING in B16-F10 cells and the possibility of its activation is linked with improved therapeutic response in vivo compared to 4T1. The effect also seems to be connected with a less dysregulated hematological system in mice with B16-F10 tumors over mice with 4T1 tumors. This highlighted the need for general insight into tumor-induced local and systemic responses to the efficiency of the proposed therapy.

Synthetic receptors that mediate antigen-dependent cell responses are transforming therapeutics, drug discovery and basic research1,2. However, established technologies such as chimeric antigen receptors3 can only detect immobilized antigens, have limited output scope and lack built-in drug control3-7. Here we engineer synthetic G-protein-coupled receptors (GPCRs) that are capable of driving a wide range of native or non-native cellular processes in response to a user-defined antigen. We achieve modular antigen gating by engineering and fusing a conditional auto-inhibitory domain onto GPCR scaffolds. Antigen binding to a fused nanobody relieves auto-inhibition and enables receptor activation by drug, thus generating programmable antigen-gated G-protein-coupled engineered receptors (PAGERs). We create PAGERs that are responsive to more than a dozen biologically and therapeutically important soluble and cell-surface antigens in a single step from corresponding nanobody binders. Different PAGER scaffolds allow antigen binding to drive transgene expression, real-time fluorescence or endogenous G-protein activation, enabling control of diverse cellular functions. We demonstrate multiple applications of PAGER, including induction of T cell migration along a soluble antigen gradient, control of macrophage differentiation, secretion of therapeutic antibodies and inhibition of neuronal activity in mouse brain slices. Owing to its modular design and generalizability, we expect PAGERs to have broad utility in discovery and translational science.

Macrophages are considered to play an important role in the development of chronic apical periodontitis (CAP). However the function of tissue resident macrophages in CAP is unclear. This study aims to investigate the potential role of macrophages of different origins in CAP.

Chemokine receptor-2 deficiency (CCR2-/-) mice and C57BL/6N mice (control group, WT mice) were used to induce apical periodontitis. The pulp of mandibular first molars of both sides were exposed to the oral environment. After 0, 7, 21, 28 days of pulp explosion, animals were sacrificed, the mandibular bones were collected and scanned with micro-CT, further processed for HE & IHC Staining to analyze the development of CAP, as well as the expression of surface markers of macrophages.

Both CCR2-/- and WT mice exhibited CCR2 negative macrophages in normal periapical area, which indicated the presence of tissue resident macrophages. CCR2 deficiency decreased the number of macrophages in periapical lesions, the M1 type macrophages' number as well as osteoclasts around the edge of the lesion decreased compared to wild type. Meanwhile CCR2 deficiency decreased the volume of periapical lesion significantly compared to wild type, but did not inhibite and disappeare the lesion thoroughly.

Monocyte-macrophage system derived macrophages promote the progression of periapical lesions, while tissue resident macrophages in periodontal ligament might also be involved in the progression of periapical lesion.

Neurodegeneration and neuroinflammation disorders are mainly the result of the deposition of various proteins, such as α-synuclein, amyloid-β and prions, which lead to the initiation and activation of inflammatory responses. Different chemokines are involved in the infiltration and movement of inflammatory leukocytes into the central nervous system (CNS) that express chemokine receptors. Dysregulation of several members of chemokines has been shown in the CNS, cerebrospinal fluid and peripheral blood of patients who have neurodegenerative disorders. Upon infiltration of various cells, they produce many inflammatory mediators such as cytokines. Besides them, some CNS-resident cells, such as neurons and astrocytes, are also involved in the pathogenesis of neurodegeneration by producing chemokines. In this review, we summarize the role of chemokines and their related receptors in the pathogenesis of neurodegeneration and neuroinflammation disorders, including multiple sclerosis, Parkinson's disease and Alzheimer's disease. Therapeutic strategies targeting chemokines or their related receptors are also discussed in this article.

Anaplastic thyroid cancer (ATC) is a lethal endocrine malignancy. It has been shown that tumor-associated macrophages (TAMs) contribute to the aggressiveness of ATC. However, stimulatory factors that could facilitate the induction and infiltration of TAMs in the ATC tumor microenvironment (TME) are not fully elucidated. In this study, we used a human leukemia monocytic cell line (THP-1) to study the differentiation of THP-1 into M2-like macrophages (M2) by conditioned media (CM) derived from each of the three human ATC cells: 8505C, THJ-11T (11T), and THJ-16T (16T). The capacity of CM to induce M2 was in the order of 16T>8505C>11T cells as determined by the expression of M2 markers (CD163, CD204, and CCL13). Cytokine arrays and ELISA assays revealed five commonly enriched cytokines (IL-6, IL-8, MCP-1, TIMP-1, and TGF-β1) in the CM derived from each of the three ATC cells. These cytokines, individually, had weak activity, but together, they mimicked full CM activity in the induction of M2. Further, they collaboratively activated STAT3, ERK, and PI3K-AKT signaling to facilitate the induction of M2 as found in CM. Importantly, we found that the CM-induced M2 could secrete soluble growth factors to promote ATC cell proliferation as evidenced by the increased Ki-67, cMYC, and cyclin D1 protein levels. Our studies identified the major stimulatory cytokines which acted collaboratively to induce M2 in the TME. Importantly, the present studies indicate that when using inhibitors to target TAMs, combination therapies would be required for effective treatment of ATC.

PLX5622 is a colony stimulating factor 1 receptor (CSF-1R) inhibitor that is known to deplete microglial cells in vivo. Recently its effects on macrophages (Mφ) were also observed in vivo. Therefore, we performed this study to assess its in vitro effects on the differentiation and functions of polarized Mφ derived from different tissues. Our findings show that addition of PLX5622 early on after ex vivo isolation hinders Mφ differentiation and survival. However, its addition post Mφ differentiation did not significantly affect the viability. Furthermore, PLX5622 affects certain functions and degree of polarization of IL-4 (M2a) Mφ but not polarization of M1-like Mφ. Our study provides novel aspects on the application of PLX5622 to study Mφ functions in vitro, where polarization is affected by CSF-1R signalling and provides distinctive evidence to its ability to affect certain populations of Mφ during in vitro differentiation and maturation.

Tissue-engineered muscle grafts (TEMGs) are a promising treatment for volumetric muscle loss (VML). In this study, human myogenic progenitors (hMPs) cultured on electrospun fibrin microfiber bundles and evaluated the therapeutic potential of engineered hMP TEMGs in the treatment of murine tibialis anterior (TA) VML injuries is employed. In vitro, the hMP TEMGs express mature muscle markers by 21 days. Upon implantation into VML injuries, the hMP TEMGs enable remarkable regeneration. To further promote wound healing and myogenesis, human adipose-derived stem/stromal cells (hASCs) as fibroadipogenic progenitor (FAP)-like cells with the potential to secrete pro-regenerative cytokines are incorporated. The impact of dose and timing of seeding the hASCs on in vitro myogenesis and VML recovery using hMP-hASC TEMGs are investigated. The hASCs increase myogenesis of hMPs when co-cultured at 5% hASCs: 95% hMPs and with delayed seeding. Upon implantation into immunocompromised mice, hMP-hASC TEMGs increase cell survival, collagen IV deposition, and pro-regenerative macrophage recruitment, but result in excessive adipose tissue growth after 28 days. These data demonstrate the interactions of hASCs and hMPs enhance myogenesis in vitro but there remains a need to optimize treatments to minimize adipogenesis and promote full therapeutic recovery following VML treatment.

Pyruvate kinase M2 (PKM2) is a key metabolic enzyme. Yet, its role in cerebral ischemia injury remains unclear. In this study we demonstrated that PKM2 expression was increased in the microglia after mouse cerebral ischemia-reperfusion (I/R) injury. We found that microglial polarization-mediated pro-inflammatory effect was mediated by PKM2 after cerebral I/R. Mechanistically, our results revealed that nuclear PKM2 mediated ischemia-induced microglial polarization through association with acetyl-H3K9. Hif-1α mediated the effect of nuclear PKM2/histone H3 on microglial polarization. PKM2-dependent Histone H3/Hif-1α modifications contributed the expression of CCL2 and induced up-regulation of microglial polarization in peri-infarct, resulting in neuroinflammation. Inhibiting nuclear translocation of microglial PKM2 reduced ischemia-induced pro-inflammation and promoted neuronal survival. Together, this study identifies nucleus PKM2 as a crucial mediator for regulating ischemia-induced neuroinflammation, suggesting PKM2 as a potential therapeutic target in ischemic stroke.

Despite viral suppression by effective combined antiretroviral therapy, HIV-1-infected individuals have an increased risk of non-AIDS-related overall morbidity, which is due to the persistent chronic inflammation exemplified by the activation of monocytes, such as increased CD16high subset, and elevated plasma level of soluble CD163 (sCD163) and soluble CD14 (sCD14). Here, we show that IL-10, which has been recognized as anti-inflammatory, induces these activated phenotypes of monocytes in vitro. IL-10 increased CD16high monocytes, which was due to the upregulation of CD16 mRNA expression and completely canceled by an inhibitor of Stat3. Moreover, IL-10 increased the production of sCD163 and sCD14 by monocytes, which was consistent with the upregulation of cell surface expression of CD163 and CD14, and mRNA expression of CD163. However, unlike the IL-10-indeuced upregulation of CD16, that of CD14 was minimally affected by the Stat3 inhibitor. Furthermore, the IL-10-induced upregulation of CD163 protein and mRNA was partially inhibited by the Stat3 inhibitor, but completely canceled by an inhibitor of AMPK, an upstream kinase of Stat3 and PI3K/Akt/mTORC1 pathways. In this study, we also found that HIV-1 pathogenic protein Nef, which is known to persist in plasma of virally-suppressed individuals, induced IL-10 production in monocyte-derived macrophages. Our results may suggest that IL-10, which is inducible by Nef-activated macrophages, is one of drivers for activated phenotypes of monocytes in virally-suppressed individuals, and that IL-10 induces the increased CD16high monocytes and elevated level of sCD163 and sCD14 through the activation of different signaling pathways.

Acute myeloid leukemia (AML) is a heterogenous malignant hemopathy, and although new drugs have emerged recently, current treatment options still show limited efficacy. Therapy resistance remains a major concern due to its contribution to treatment failure, disease relapse, and increased mortality among patients. The underlying mechanisms of resistance to therapy are not fully understood, and it is crucial to address this challenge to improve therapy. Macrophages are immune cells found within the bone marrow microenvironment (BMME), of critical importance for leukemia development and progression. One defining feature of macrophages is their plasticity, which allows them to adapt to the variations in the microenvironment. While this adaptability is advantageous during wound healing, it can also be exploited in cancer scenarios. Thus, clinical and preclinical investigations that target macrophages as a therapeutic strategy appear promising. Existing research indicates that targeting macrophages could enhance the effectiveness of current AML treatments. This review addresses the importance of macrophages as therapeutic targets including relevant drugs investigated in clinical trials such as pexidartinib, magrolimab or bexmarilimab, but also provides new insights into lesser-known therapies, like macrophage receptor with a collagenous structure (MACRO) inhibitors and Toll-like receptor (TLR) agonists.

Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) supplements have exhibited inconsistent effects on cancer risk, and their potential efficacy as cancer preventive agents has been increasingly questioned, especially in recent large randomized clinical trials. The role of host factors that govern EPA and DHA metabolism in relation to their impact on carcinogenesis remains understudied. Resolvins, the products of EPA and DHA oxidative metabolism, demonstrate intriguing antitumorigenic effects through mechanisms such as promoting macrophage phagocytosis of cell debris and inhibiting the production of proinflammatory chemokines and cytokines by tumor-associated macrophages (TAMs), which are crucial for cancer progression. However, clinical studies have not yet shown a significant increase in target tissue levels of resolvins with EPA and DHA supplementation. 15-Lipoxygenase-1 (ALOX15), a key enzyme in EPA and DHA oxidative metabolism, is often lost in various major human cancers, including precancerous and advanced colorectal cancers. Further research is needed to elucidate whether the loss of ALOX15 expression in colorectal precancerous and cancerous cells affects EPA and DHA oxidative metabolism, the formation of resolvins, and subsequently carcinogenesis. The findings from these studies could aid in the development of novel and effective chemoprevention interventions to reduce cancer risk.

Pseudomonas aeruginosa is a frequent cause of antimicrobial-resistant hospital-acquired pneumonia, especially in critically ill patients. Inflammation triggered by P. aeruginosa infection is necessary for bacterial clearance but must be spatially and temporally regulated to prevent further tissue damage and bacterial dissemination. Emerging data have shed light on the pro-resolving actions of angiotensin-(1-7) [Ang-(1-7)] signaling through the G protein-coupled receptor Mas (MasR) during infections. Herein, we investigated the role of the Ang-(1-7)/Mas axis in pneumonia caused by P. aeruginosa by using genetic and pharmacological approach and found that Mas receptor-deficient animals developed a more severe form of pneumonia showing higher neutrophilic infiltration into the airways, bacterial load, cytokines, and chemokines production and more severe pulmonary damage. Conversely, treatment of pseudomonas-infected mice with Ang-(1-7) was able to decrease neutrophilic infiltration in airways and lungs, local and systemic levels of pro-inflammatory cytokines and chemokines, and increase the efferocytosis rates, mitigating lung damage/dysfunction caused by infection. Notably, the therapeutic association of Ang-(1-7) with antibiotics improved the survival rates of mice subjected to lethal inoculum of P. aeruginosa, extending the therapeutic window for imipenem. Mechanistically, Ang-(1-7) increased phagocytosis of bacteria by neutrophils and macrophages to accelerate pathogen clearance. Altogether, harnessing the Ang-(1-7) pathway during infection is a potential strategy for the development of host-directed therapies to promote mechanisms of resistance and resilience to pneumonia.

N-acetyltransferase 10 (NAT10) plays a crucial role in the occurrence and development of various tumors. However, the current regulatory mechanism of NAT10 in tumors is limited to its presence in tumor cells. Here, we aimed to reveal the role of NAT10 in intrahepatic cholangiocarcinoma (ICC) and investigate its effect on macrophage polarization in the tumor microenvironment (TME).

The correlation between NAT10 and ICC clinicopathology was analyzed using tissue microarray (TMA), while the effect of NAT10 on ICC proliferation was verified in vitro and in vivo. Additionally, the downstream target of NAT10, C-C motif chemokine ligand 2 (CCL2), was identified by Oxford Nanopore Technologies full-length transcriptome sequencing, RNA immunoprecipitation-quantitative polymerase chain reaction, and coimmunoprecipitation experiments. It was confirmed by co-culture that ICC cells could polarize macrophages towards M2 type through the influence of NAT10 on CCL2 protein expression level. Through RNA-sequencing, molecular docking, and surface plasmon resonance (SPR) assays, it was confirmed that berberine (BBR) can specifically bind CCL2 to inhibit ICC development.

High expression level of NAT10 was associated with poor clinicopathological manifestations of ICC. In vitro, the knockdown of NAT10 inhibited the proliferative activity of ICC cells and tumor growth in vivo, while its overexpression promoted ICC proliferation. Mechanically, by binding to CCL2 messenger RNA, NAT10 increased CCL2 protein expression level in ICC and their extracellular matrix, thereby promoting the proliferation of ICC cells and M2-type polarization of macrophages. BBR can target CCL2, inhibit ICC proliferation, and reduce M2-type polarization of macrophages.

NAT10 promotes ICC proliferation and M2-type polarization of macrophages by up-regulating CCL2, whereas BBR inhibits ICC proliferation and M2-type polarization of macrophages by inhibiting CCL2.

Non-alcoholic fatty liver disease (NAFLD) and its more advanced form, non-alcoholic steatohepatitis (NASH), have become global health challenges with significant morbidity and mortality rates. NAFLD encompasses several liver diseases, ranging from simple steatosis to more severe inflammatory and fibrotic forms. Ultimately, this can lead to liver cirrhosis and hepatocellular carcinoma. The intricate role of hepatic macrophages, particularly Kupffer cells (KCs) and monocyte-derived macrophages (MoMFs), in the pathogenesis of NAFLD and NASH, has received increasing attention. Hepatic macrophages can interact with hepatocytes, hepatic stellate cells, and endothelial cells, playing a crucial role in maintaining homeostasis. Paradoxically, they also participate in the pathogenesis of some liver diseases. This review highlights the fundamental role of hepatic macrophages in the pathogenesis of NAFLD and NASH, emphasizing their plasticity and contribution to inflammation and fibrosis, and hopes to provide ideas for subsequent experimental research and clinical treatment.

Many chronic inflammatory diseases are attributed to disturbances in host-microbe interactions, which drive immune-mediated tissue damage. Depending on the anatomic setting, a chronic inflammatory disease can exert unique local and systemic influences, which provide an exceptional opportunity for understanding disease mechanism and testing therapeutic interventions. The oral cavity is an easily accessible environment that allows for protective interventions aiming at modulating the immune response to control disease processes driven by a breakdown of host-microbe homeostasis. Periodontal disease (PD) is a prevalent condition in which quantitative and qualitative changes of the oral microbiota (dysbiosis) trigger nonresolving chronic inflammation, progressive bone loss, and ultimately tooth loss. Here, we demonstrate the therapeutic benefit of local sustained delivery of the myeloid-recruiting chemokine (C-C motif) ligand 2 (CCL2) in murine ligature-induced PD using clinically relevant models as a preventive, interventional, or reparative therapy. Local delivery of CCL2 into the periodontium inhibited bone loss and accelerated bone gain that could be ascribed to reduced osteoclasts numbers. CCL2 treatment up-regulated M2-macrophage and downregulated proinflammatory and pro-osteoclastic markers. Furthermore, single-cell ribonucleic acid (RNA) sequencing indicated that CCL2 therapy reversed disease-associated transcriptomic profiles of murine gingival macrophages via inhibiting the triggering receptor expressed on myeloid cells-1 (TREM-1) signaling in classically activated macrophages and inducing protein kinase A (PKA) signaling in infiltrating macrophages. Finally, 16S ribosomal ribonucleic acid (rRNA) sequencing showed mitigation of microbial dysbiosis in the periodontium that correlated with a reduction in microbial load in CCL2-treated mice. This study reveals a novel protective effect of CCL2 local delivery in PD as a model for chronic inflammatory diseases caused by a disturbance in host-microbe homeostasis.

Sporadic vestibular schwannomas (VSs) often exhibit slow or negligible growth. Nevertheless, some VSs increase significantly in volume within a few months or grow continuously. Recent evidence indicates a role of inflammation in promoting VS growth. Therefore, our study aimed to identify cytokines, which are associated with larger VSs. The expression of different cytokines in VS tumor samples and VS primary cultures was investigated. Additionally, the concentration of cytokines in cell culture supernatants of VS primary cultures and cerebrospinal fluid (CSF) of VS patients and healthy controls were determined. Correlation analysis of cytokine levels with tumor volume, growth rate, Koos grade, age, and hearing was examined with Spearman's-rank test. The mRNA expression of CC-chemokine ligand (CCL) 18, growth differentiation factor (GDF) 15, and interferon regulatory factor 4 correlated positively with tumor volume. Moreover, the amount of GDF15 in the cell culture supernatant of primary cells correlated positively with tumor volume. The concentrations of the cytokines CCL2, CCL5, and CCL18 and transforming growth factor beta (TGFB) 1 in the CSF of the patients were significantly different from those in the CSF controls. Inhibition of immune cell infiltration could be a putative approach to prevent and control VS growth.

Inflammation-induced remodelling of gestational tissues that underpins spontaneous preterm birth (sPTB, delivery < 37 weeks' gestation) may vary by race and context. To explore relationships between markers of these pathological processes, we (a) characterised the cervicovaginal fluid (CVF) cytokine profiles of pregnant South African women at risk of PTB; (b) determined CVF matrix-metalloproteinase-9 (MMP-9) and its regulator tissue inhibitor of metalloproteinase-1 (TIMP-1); and (c) explored the predictive potential of these markers for sPTB.

The concentrations of 10 inflammatory cytokines and MMP-9 and TIMP-1 were determined by ELISA in CVF samples from 47 non-labouring women at high risk of PTB. We studied CVF sampled at three gestational time points (GTPs): GTP1 (20-22 weeks, n = 37), GTP2 (26-28 weeks, n = 40), and GTP3 (34-36 weeks, n = 29) and analysed for changes in protein concentrations and predictive capacities (area under the ROC curve (AUC) and 95% confidence interval (CI)) for sPTB.

There were 11 (GTP1), 13 (GTP2), and 6 (GTP3) women who delivered preterm within 85.3 ± 25.9, 51.3 ± 15.3, and 11.8 ± 7.5 (mean ± SD) days after assessment, respectively. At GTP1, IL-8 was higher (4-fold, p = 0.02), whereas GM-CSF was lower (~1.4-fold, p = 0.03) in the preterm compared with term women with an average AUC = 0.73. At GTP2, IL-1β (18-fold, p < 0.0001), IL-8 (4-fold, p = 0.03), MMP-9 (17-fold, p = 0.0007), MMP-9/TIMP-1 ratio (9-fold, p = 0.004), and MMP-9/GM-CSF ratio (87-fold, p = 0.005) were higher in preterm compared with term women with an average AUC = 0.80. By contrast, IL-10 was associated with term delivery with an AUC (95% CI) = 0.75 (0.55-0.90). At GTP3, IL-1β (58-fold, p = 0.0003), IL-8 (12-fold, p = 0.002), MMP-9 (296-fold, p = 0.03), and TIMP-1 (35-fold, p = 0.01) were higher in preterm compared with term women with an average AUC = 0.85. Elevated IL-1β was associated with delivery within 14 days of assessment with AUC = 0.85 (0.67-0.96). Overall, elevated MMP-9 at GTP3 had the highest (13.3) positive likelihood ratio for distinguishing women at risk of sPTB. Lastly, a positive correlation between MMP-9 and TIMP-1 at all GTPs (ρ ≥ 0.61, p < 0.01) for women delivering at term was only observed at GTP1 for those who delivered preterm (ρ = 0.70, p < 0.03).

In this cohort, sPTB is associated with gestation-dependent increase in pro-inflammatory cytokines, decreased IL-10 and GM-CSF, and dysregulated MMP-9-TIMP-1 interaction. Levels of cytokine (especially IL-1β) and ECM remodelling proteins rise significantly in the final 2 weeks before the onset of labour when sPTB is imminent. The signalling mechanisms for these ECM remodelling observations remain to be elucidated.

Beyond demographic and immune factors, metabolic considerations, particularly metformin's recognized impact in oncology, warrant exploration in treating pancreatic cancer. This study aimed to investigate the influence of metformin on patient survival and its potential correlation with distinct immune profiles in pancreatic ductal adenocarcinoma (PDAC) tumors.

We included 82 upfront resected and 66 gemcitabine-based neoadjuvant chemoradiotherapy (nCRT)-treated patients from the PREOPANC randomized controlled trial (RCT). Transcriptomic NanoString immunoprofiling was performed for a subset of 96 available resected specimens.

Disparities in survival outcomes and immune profiles were apparent between metformin and non-metformin users in upfront resected patients but lacking in nCRT-treated patients. Compared to non-metformin users, upfront resected metformin users showed a higher median overall survival (OS) of 29 vs 14 months and a better 5-year OS rate of 19% vs 5%. Furthermore, metformin use was a favorable prognostic factor for OS in the upfront surgery group (HR = 0.56; 95% CI = 0.32 to 0.99). Transcriptomic data revealed that metformin users significantly underexpressed genes related to pro-tumoral immunity, including monocyte to M2 macrophage polarization and activation. Furthermore, the relative abundance of anti-inflammatory CD163+ MRC1+ M2 macrophages in non-metformin users and immune-activating CD1A+ CD1C+ dendritic cells in metformin users was heightened (P < .001).

This study unveils immune profile changes resulting from metformin use in upfront resected pancreatic cancer patients, possibly contributing to prolonged survival outcomes. Specifically, metformin use may decrease the abundance and activity of pro-tumoral M2 macrophages and increase the recruitment and function of tumor-resolving DCs, favoring antitumor immunity.[PREOPANC trial EudraCT: 2012-003181-40].

Hepatocellular carcinoma (HCC) is a highly heterogeneous malignancy with high incidence, recurrence, and metastasis rates. The emergence of immunotherapy has improved the treatment of advanced HCC, but problems such as drug resistance and immune-related adverse events still exist in clinical practice. The immunosuppressive tumor microenvironment (TME) of HCC restricts the efficacy of immunotherapy and is essential for HCC progression and metastasis. Therefore, it is necessary to elucidate the mechanisms behind immunosuppressive TME to develop and apply immunotherapy. This review systematically summarizes the pathogenesis of HCC, the formation of the highly heterogeneous TME, and the mechanisms by which the immunosuppressive TME accelerates HCC progression and metastasis. We also review the status of HCC immunotherapy and further discuss the existing challenges and potential therapeutic strategies targeting immunosuppressive TME. We hope to inspire optimizing and innovating immunotherapeutic strategies by comprehensively understanding the structure and function of immunosuppressive TME in HCC.

This review provides an in-depth examination of the role that tumor-associated macrophages (TAMs) play in the progression of prostate cancer (PCa), with a particular focus on the factors influencing the polarization of M1 and M2 macrophages and the implications of targeting these cells for cancer progression. The development and prognosis of PCa are significantly influenced by the behavior of macrophages within the tumor microenvironment. M1 macrophages typically exhibit anti-tumor properties by secreting pro-inflammatory cytokines such as interferon-gamma (IFN-γ) and tumor necrosis factor-alpha (TNF-α), thereby enhancing the immune response. Conversely, M2 macrophages contribute to tumor cell migration and invasion through the production of factors like arginase-1 (Arg1) and interleukin-10 (IL-10). This review not only explores the diverse factors that affect macrophage polarization but also delves into the potential therapeutic strategies targeting macrophage polarization, including the critical roles of non-coding RNA and exosomes in regulating this process. The polarization state of macrophages is highlighted as a key determinant in PCa progression, offering a novel perspective for clinical treatment. Future research should concentrate on gaining a deeper understanding of the molecular mechanisms underlying macrophage polarization and on developing effective targeted therapeutic strategies. The exploration of the potential of combination therapies to improve treatment efficacy is also emphasized. By emphasizing the importance of macrophages as a therapeutic target in PCa, this review aims to provide valuable insights and research directions for clinicians and researchers.

Many cancers metastasize to the pleura, resulting in effusions that cause dyspnea and discomfort. Regardless of the tissue of origin, pleural malignancies are aggressive and uniformly fatal, with no treatment shown to prolong life. The pleural mesothelial monolayer is joined by tight junctions forming a contained bioreactor-like space, concentrating cytokines and chemokines secreted by the mesothelium, tumor, and infiltrating immune cells. This space represents a unique environment that profoundly influences tumor and immune cell behavior. Defining the pleural secretome is an important step in the rational development localized intrapleural immunotherapy.

We measured cytokine/chemokine content of 252 malignant pleural effusion (MPE) samples across multiple cancers using a 40-analyte panel and Luminex multiplexing technology.

Eleven analytes were consistently present in concentrations ≥ 10.0 pM: CXCL10/IP10 (geometric mean = 672.3 pM), CCL2/MCP1 (562.9 pM), sIL-6Rα (403.1 pM), IL-6 (137.6 pM), CXCL1/GRO (80.3 pM), TGFβ1 (76.8 pM), CCL22/MDC (54.8 pM), CXCL8/IL-8 (29.2 pM), CCL11/Eotaxin (12.6 pM), IL-10 (11.3 pM), and G-CSF (11.0 pM). All are capable of mediating chemotaxis, promotion of epithelial to mesenchymal transition, or immunosuppression, and many of are reportedly downstream of a pro-inflammatory cytokine cascade mediated by cytokine IL-6 and its soluble receptor.

The data indicate high concentrations of several cytokines and chemokines across epithelial cancers metastatic to the pleura and support the contention that the pleural environment is the major factor responsible for the clinical course of MPE across cancer types. A sIL-6Rα to IL-6 molar ratio of 2.7 ensures that virtually all epithelial, immune and vascular endothelial cells in the pleural environment are affected by IL-6 signaling. The central role likely played by IL-6 in the pathogenesis of MPE argues in favor of a therapeutic approach targeting the IL-6/IL-6R axis.

Osteoarthritis (OA) is characterized by a complex interplay of molecular signals orchestrated by the CCL2/CCR2 axis. The pathogenesis of OA has been revealed to be influenced by a multifaceted effect of CCL2/CCR2 signaling on inflammation, cartilage degradation, and joint homeostasis. The CCL2/CCR2 axis promotes immune cell recruitment and tips the balance toward degeneration by influencing chondrocyte behavior. Insights into these intricate pathways will offer novel therapeutic approaches, paving the way for targeted interventions that may redefine OA management in the future. This review article explores the molecular symphony through the lens of the CCL2/CCR2 axis, providing a harmonious blend of current knowledge and future directions on OA treatment. Furthermore, in this study, through a meticulous review of recent research, the key players and molecular mechanisms that amplify the catabolic cascade within the joint microenvironment are identified, and therapeutic approaches to targeting the CCL2/CCR axis are discussed.

M2 macrophages are known to play a significant role in the progression of triple-negative breast cancer (TNBC) by creating an immunosuppressive microenvironment. The aim of this study is to investigate the impact of M2 macrophages on TNBC and their correlation with programmed death-ligand 1 (PD-L1) expression.

We employed a co-culture system to analyze the role of the mutual regulation of M2 macrophages and TNBC cells. Employing a multifaceted approach, including bioinformatics analysis, Western blotting, flow cytometry analysis, ELISA, qRT-PCR, lentivirus infection, mouse models, and IHC, we aimed to elucidate the influence and mechanism of M2 macrophages on PD-L1 expression.

The results showed a substantial infiltration of M2 macrophages in TNBC tissue, which demonstrated a positive correlation with PD-L1 expression. CXCL1 exhibited abnormally high expression in M2 macrophages and enhanced the expression of PD-L1 in TNBC cells. Notably, silencing CXCL1 or its receptor CXCR2 inhibited M2 macrophages-induced expression of PD-L1. Mechanistically, CXCL1 derived from M2 macrophages binding to CXCR2 activated the PI3K/AKT/NF-κB signaling pathway, resulting in increased PD-L1 expression in TNBC.

Broadly speaking, these results provide evidence for the immunosuppressive role of M2 macrophages and CXCL1 in TNBC cells, indicating their potential as therapeutic biomarkers.

The innate immune response is crucial to inflammation, but how neutrophils and macrophages act in bone repair and tissue engineering treatment strategies await clarification. In this study, it is found that N2 neutrophils release stronger "eat me" signals to induce macrophage phagocytosis and polarize into the M2 anti-inflammatory phenotype. Guided by this biological mechanism, a mesoporous bioactive glass scaffold (MBG) is filled with hyaluronic acid methacryloyl (HAMA) hydrogel loaded with Transforming growth factor-β1 (TGFβ1) adenovirus (Ad@H), constructing a genetically engineered composite scaffold (Ad@H/M). The scaffold not only has good hydrophilicity and biocompatibility, but also provides mechanical stress support for bone repair. Adenovirus infection quickly induces N2 neutrophils, upregulating NF-κB and MAPK signaling pathways through Toll-like receptor 4 (TLR4) to promote the inflammatory response and macrophage phagocytosis. Macrophages perform phagocytosis and polarize towards the M2 phenotype, mediating the inflammatory response by inhibiting the PI3K-AKT-NF-κB pathway, maintaining homeostasis of the osteogenic microenvironment. The role of the Ad@H/M scaffold in regulating early inflammation and promoting long-term bone regeneration is further validated in vivo. In brief, this study focuses on the cascade of reactions between neutrophils and macrophage subtypes, and reports a composite scaffold that coordinates the innate immune response to promote bone repair.

Triple-negative breast cancer (TNBC) has greater infiltration of M2-like macrophages (TAMs), which enhances cancer cell invasion and leads to a poor prognosis. TNBC progression is mediated by both tumor cells and the tumor microenvironment (TME). Here we elucidate the mechanism of the interaction between TNBC cells and TAMs. In this study, we confirmed that CD44v5 is highly expressed in TNBC, which drives TNBC cell metastasis and promotes TAM polarization by co-localizing with IL4Rα and inhibiting its internalization and degradation, thereby promoting activation of the STAT3/IL6 signaling axis. At the same time, TAMs also facilitate TNBC cell metastasis by secreting IL-4, IL-6, and other cytokines, in which the IL-4/IL-4R/STAT3/IL-6 signaling axis plays the same role for TNBC cells responding to TAMs. Moreover, we found that the above progress could be suppressed when the CD44v5 domain was blocked. We demonstrated that the CD44v5/IL-4R/STAT3/IL-6 signaling pathway plays a key role in TNBC cell metastasis, and in TNBC cells inducing TAM polarization and responding to TAMs, promoting metastasis. Collectively, we suggest that the CD44v5 domain may be a promising target for regulating the TME of TNBC as well as treating TNBC.

Through Smad3-dependent signalings, transforming growth factor-β (TGF-β) suppresses the development, maturation, cytokine productions and cytolytic functions of NK cells in cancer. Silencing Smad3 remarkably restores the cytotoxicity of NK-92 against cancer in TGF-β-rich microenvironment, but its effects on the immunoregulatory functions of NK cells remain obscure. In this study, we identified Smad3 functioned as a transcriptional repressor for CSF2 (GM-CSF) in NK cells. Therefore, disrupting Smad3 largely mitigated TGF-β-mediated suppression on GM-CSF production by NK cells. Furthermore, silencing GM-CSF in Smad3 knockout NK cells substantially impaired their anti-lung carcinoma effects. In-depth study demonstrated that NK-derived GM-CSF strengthened T cell immune responses by stimulating dendritic cell differentiation and M1 macrophage polarization. Meanwhile, NK-derived GM-CSF promoted the survival of neutrophils, which in turn facilitated the terminal maturation of NK cells, and subsequently boosted NK-cell mediated cytotoxicity against lung carcinoma. Thus, Smad3-silenced NK-92 (NK-92-S3KD) may serve as a promising immunoadjuvant therapy with clinical translational value given its robust cytotoxicity against malignant cells and immunostimulatory functions to reinforce the therapeutic effects of other immunotherapies.

Inflammasomes are immune complexes whose activation leads to the release of pro-inflammatory cytokines IL-18 and IL-1β. Type I IFNs play a role in fighting infection and stimulate the expression of IFN-stimulated genes (ISGs) involved in inflammation. Despite the importance of these cytokines in inflammation, the regulation of inflammasomes by type I IFNs remains poorly understood. Here, we analysed RNA-sequencing data from patients with monogenic interferonopathies and found an up-regulation of several inflammasome-related genes. To investigate the effect of type I IFN on the inflammasome, we treated human monocyte-derived macrophages with IFN-α and observed an increase in CASP1 and GSDMD mRNA levels over time, whereas IL1B and NLRP3 were not directly correlated to IFN-α exposure time. IFN-α treatment reduced the release of mature IL-1β and IL-18, but not caspase-1, in response to ATP-mediated NLRP3 inflammasome activation, suggesting regulation occurs at cytokine expression levels and not the inflammasome itself. However, more studies are required to investigate how regulation by IFN-α occurs and impacts NLRP3 and other inflammasomes at both transcriptional and post-translational levels.

Kidney renal clear cell carcinoma (KIRC) is a highly immune-infiltrated kidney cancer with the highest mortality rate and the greatest potential for invasion and metastasis. Solute carrier family 11 member1 (SLC11A1) is a phagosomal membrane protein located in monocytes and plays a role in innate immunity, autoimmune diseases, and infection, but its expression and biological role in KIRC is still unknown. In this study, we sought to investigate the potential value of SLC11A1 according to tumor growth and immune response in KIRC. TIMER and UALCAN database was used to analyze the expression feature and prognostic significance of SLC11A1 and its correlation with immune-related biomarkers in KIRC. Proliferation, migration, and invasion were measured using colony formation, EdU, and transwell assays. Role of SLC11A1 on KIRC tumor growth was examined by the xenograft tumor model in vivo. Effects of KIRC cells on macrophage polarization and the proliferation and apoptosis of CD8+ T cells were analyzed using flow cytometry assays. Herein, SLC11A1 was highly expressed in KIRC tissues and cell lines. SLC11A1 downregulation repressed KIRC cell proliferation, migration, invasion, macrophage, and lymphocyte immunity in vitro, as well as hindered tumor growth in vivo. SLC11A1 is significantly correlated with immune cell infiltration and immune-related biomarkers. In KIRC patients, SLC11A1 is highly expressed and positively correlated with the immune-related factors CCL2 and PD-L1. SLC11A1 induced CCL2 and PD-L1 expression, thereby activating the JAK/STAT3 pathway. SLC11A1 deficiency constrained KIRC cell malignant phenotypes and immune response via regulating CCL2 and PD-L1-mediated JAK/STAT3 pathway, providing a promising therapeutic target for KIRC treatment.

Better understanding of the host responses to Mycobacterium tuberculosis infections is required to prevent tuberculosis and develop new therapeutic interventions. The host transcription factor BHLHE40 is essential for controlling M. tuberculosis infection, in part by repressing Il10 expression, where excess IL-10 contributes to the early susceptibility of Bhlhe40-/- mice to M. tuberculosis infection. Deletion of Bhlhe40 in lung macrophages and dendritic cells is sufficient to increase the susceptibility of mice to M. tuberculosis infection, but how BHLHE40 impacts macrophage and dendritic cell responses to M. tuberculosis is unknown. In this study, we report that BHLHE40 is required in myeloid cells exposed to GM-CSF, an abundant cytokine in the lung, to promote the expression of genes associated with a proinflammatory state and better control of M. tuberculosis infection. Loss of Bhlhe40 expression in murine bone marrow-derived myeloid cells cultured in the presence of GM-CSF results in lower levels of proinflammatory associated signaling molecules IL-1β, IL-6, IL-12, TNF-α, inducible NO synthase, IL-2, KC, and RANTES, as well as higher levels of the anti-inflammatory-associated molecules MCP-1 and IL-10 following exposure to heat-killed M. tuberculosis. Deletion of Il10 in Bhlhe40-/- myeloid cells restored some, but not all, proinflammatory signals, demonstrating that BHLHE40 promotes proinflammatory responses via both IL-10-dependent and -independent mechanisms. In addition, we show that macrophages and neutrophils within the lungs of M. tuberculosis-infected Bhlhe40-/- mice exhibit defects in inducible NO synthase production compared with infected wild-type mice, supporting that BHLHE40 promotes proinflammatory responses in innate immune cells, which may contribute to the essential role for BHLHE40 during M. tuberculosis infection in vivo.

Past research has identified that cancer cells sustain several cancer hallmarks by impairing function of the endolysosomal system (ES). Thus, maintaining the functional integrity of endolysosomes is crucial, which heavily relies on two key protein families: soluble hydrolases and endolysosomal membrane proteins. Particularly members of the TPC (two-pore channel) and TRPML (transient receptor potential mucolipins) families have emerged as essential regulators of ES function as a potential target in cancer therapy. Targeting TPCs and TRPMLs has demonstrated significant impact on multiple cancer hallmarks, including proliferation, growth, migration, and angiogenesis both in vitro and in vivo. Notably, endosomes and lysosomes also actively participate in various immune regulatory mechanisms, such as phagocytosis, antigen presentation, and the release of proinflammatory mediators. Yet, knowledge about the role of TPCs and TRPMLs in immunity is scarce. This prompts a discussion regarding the potential role of endolysosomal ion channels in aiding cancers to evade immune surveillance and destruction. Specifically, understanding the interplay between endolysosomal ion channels and cancer immunity becomes crucial. Our review aims to comprehensively explore the current knowledge surrounding the roles of TPCs and TRPMLs in immunity, whilst emphasizing the critical need to elucidate their specific contributions to cancer immunity by pointing out current research gaps that should be addressed.

Extremely preterm (EPT; gestational week < 28 + 0, < 1000 g) neonates are vulnerable to infections and necrotising enterocolitis, important contributors to mortality and morbidity. However, knowledge regarding their immune maturation remains limited. We here investigated the longitudinal development of functional T-cell capacity in EPT infants.

Peripheral blood mononuclear cells were isolated at 14th and 28th day (D) and at gestational week 36 + 0 (Gw36) from EPT infants, participated in a randomised, double-blind, placebo-controlled study of Lactobacillus reuteri DSM 17938 probiotic supplementation. Blood collected from 25 full-term (FT) infants at D14 was used as control. The secretion of immune mediators was determined through comprehensive Luminex panels after stimulation with human T-cell activator CD3/CD28 beads.

The levels of many mediators were low in EPT infants at D14, whereas the secretion of several chemokines was higher in EPT than in FT infants. Furthermore, Th2:Th1 cytokine ratios were higher in EPT than in FT infants. Progressively elevated secretion of, for example, IFN-γ, TNF and IL-17A in EPT infants was observed from D14 to D28 and then at Gw36. Elevated levels were observed for many proinflammatory mediators at D28. Probiotic supplementation or perinatal factors (e.g. clinical chorioamnionitis, preeclampsia and delivery mode) did not influence the cytokine and chemokine responses.

Immune mediators induced by T-cell activation in EPT infants were mainly reduced at D14 and Th2 skewed compared to those in FT infants, but mostly recovered at Gw36, indicating immune maturation. Increased proinflammatory responses at D28 may be related to the heightened risk of severe immune-associated complications seen in EPT infants.

Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), omega-3 polyunsaturated fatty acids (ω-3 PUFAs) derived from fish oil, are widely used as dietary supplements and FDA-approved treatments for hypertriglyceridemia. However, studies investigating the effects of EPA and DHA on colorectal carcinogenesis (CRC) have yielded conflicting results. The factors that determine these discrepant results remain unknown. Resolvins, oxidative metabolites of EPA and DHA, inhibit key pro-tumorigenic cytokine and chemokine signaling of colorectal cancer (e.g., IL-6, IL-1β, and CCL2). 15-lipoxygenase-1 (ALOX15), a critical enzyme for resolvin generation is commonly lost during human CRC. Whether ALOX15 expression, as a host factor, modulates the effects of EPA and DHA on CRC remains unknown. Therefore, we evaluated the effects of ALOX15 transgenic expression in colonic epithelial cells on resolvin generation by EPA and DHA and CRC in mouse models representative of human CRC. Our results revealed that 1) EPA and DHA effects on CRC were diverse, ranging from suppressive to promotive, and these effects were occasionally altered by the formulations of EPA and DHA (free fatty acid, ethyl ester, triglyceride); 2) EPA and DHA uniformly suppressed CRC in the presence of intestinal ALOX15 transgenic expression, which induced the production of resolvins, decreased colonic CCL3-5 and CXCL-5 expression and tumor associated macrophages while increasing CD8 T cell abundance in tumor microenvironment; and 3) RvD5, the predominant resolvin produced by ALOX15, inhibited macrophage generation of pro-tumorigenic cytokines. These findings demonstrate the significance of intestinal ALOX15 expression as a host factor in determining the effects of EPA and DHA on CRC.

Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are widely used as dietary supplements and FDA-approved treatments for hypertriglyceridemia. Studies of EPA and DHA effects on colorectal carcinogenesis (CRC) have revealed inconsistencies; factors determining the direction of their impact on CRC have remained unidentified. Our data show that EPA and DHA effects on CRC were divergent and occasionally influenced by their formulations. More importantly, intestinal 15-lipoxgenase-1 (ALOX15) expression modulated EPA and DHA effects on CRC, leading to their consistent suppression of CRC. ALOX15 promoted EPA and DHA oxidative metabolism to generate resolvins, which inhibited key pro-tumorigenic inflammatory cytokines and chemokines, including IL-6. IL-1β, and CCL2. ALOX15 is therefore an important host factor in determining EPA and DHA effects on CRC.

C-C chemokine receptor type 2 (CCR2) is a monocyte chemokine associated with oxidative stress and inflammation. Kidney stones (KS) are composed of calcium oxalate (CaOx), which trigger renal oxidative stress and inflammatory. This study aims to evaluate the effects of CCR2 on KS in vivo and in vitro. Eight-week-old male C57BL/6J mice were intraperitoneally injected with glyoxylate (GOX) daily to establish a KS model, and along with CCR2 antagonist (INCB3344) treatment on days 2, 4, and 6. The results showed that CCR2 antagonist reduced renal injury markers (blood urea nitrogen and serum creatinine), alleviated renal tubular injury and CaOx crystal deposition. CCR2 antagonist also decreased CCR2 expression induced by GOX treatment and increased Nrf2 expression. GOX treatment promoted malondialdehyde (MDA) production, decreased glutathione (GSH) content, and inhibited catalase (CAT) and superoxide dismutase (SOD) activity, however, CCR2 antagonist attenuated the above effects of GOX. CCR2 antagonist had inhibitory effects on GOX-induced inflammatory cytokine expression (IL1B, IL6 and MCP1), and inhibited apoptosis by increasing Bcl-2 expression and decreasing Bax and cleaved-caspase 3 expression. In vitro experiments were performed by co-culture model of CaOx-induced damaged HK-2 cells and macrophage-like THP-1 cells. CCR2 antagonist inhibited CaOx-induced THP-1 cell M1 polarization by decreasing the TNF-α, IL6 and iNOS levels, and further alleviated CaOx-induced oxidative stress damage, inflammatory response and apoptosis of HK-2 cells. The study suggests that CCR2 antagonist may be resistant to CaOx crystals-induced oxidative stress and inflammation by inhibiting macrophage M1 polarization.

Macrophages are central innate immune cells whose function declines with age. The molecular mechanisms underlying age-related changes remain poorly understood, particularly in human macrophages. We report a substantial reduction in phagocytosis, migration, and chemotaxis in human monocyte-derived macrophages (MDMs) from older (>50 years old) compared with younger (18-30 years old) donors, alongside downregulation of transcription factors MYC and USF1. In MDMs from young donors, knockdown of MYC or USF1 decreases phagocytosis and chemotaxis and alters the expression of associated genes, alongside adhesion and extracellular matrix remodeling. A concordant dysregulation of MYC and USF1 target genes is also seen in MDMs from older donors. Furthermore, older age and loss of either MYC or USF1 in MDMs leads to an increased cell size, altered morphology, and reduced actin content. Together, these results define MYC and USF1 as key drivers of MDM age-related functional decline and identify downstream targets to improve macrophage function in aging.