Identification of FCN1 as a novel macrophage infiltration-associated biomarker for diagnosis of pediatric inflammatory bowel diseases

Macrophage heterogeneity in autoimmune diseases

The pathogenesis of autoimmune diseases (AIDs) is complex and their etiology remains unclear, with multiple cell types involved in the disease progression. Macrophages, as a crucial immune cell population in AIDs, play a pivotal role in maintaining immune homeostasis. In traditional research, macrophages are frequently oversimplified into the M1 and M2 polarized subtypes. The advent of single-cell RNA sequencing (scRNA-seq) technology has significantly advanced high-throughput research in the life sciences, enabling in-depth investigations at the cellular and molecular levels. This technology has revealed the significant heterogeneity of macrophages, further enhancing our understanding of their development, phenotypic diversity, and functional plasticity. Additionally, it provides a novel perspective for exploring the molecular mechanisms underlying various diseases. In this review, we comprehensively explore the heterogeneity of macrophages across different AIDs, and summarize potential therapeutic targets for macrophage-directed interventions, aiming to provide valuable theoretical insights and novel research directions to advance precision therapy and related studies in AIDs.

Role of Pyroptosis in inflammatory bowel disease

Inflammatory bowel disease (IBD) is a serious chronic condition marked by persistent and recurrent intestinal ulcers. Although the exact cause of IBD remains unclear, it is generally accepted that a complex interaction among dietary factors, gut microbiota, and immune responses in genetically predisposed individuals contributes to its development. Pyroptosis, an inflammatory form of programmed cell death activated by inflammasomes, is marked by the rupture of cell membranes and the subsequent release of inflammatory mediators. Emerging evidence indicates that pyroptosis plays a crucial role in the pathogenesis of IBD. Moderate pyroptosis activation can enhance intestinal immune defenses, while excessive inflammasome activation can trigger an inflammatory cascade, resulting in increased damage to intestinal tissues. This article reviews the molecular mechanisms underlying pyroptosis and highlights its role in the onset and progression of IBD. Furthermore, We explore recent advancements in IBD treatment, focusing on small molecule compounds that specifically target and inhibit pyroptosis.

Epithelial-Immune-Stromal Interactions Define Divergent Repair and Fibrosis Pathways After Acute Kidney Injury in Human Renal Transplants

Acute kidney injury (AKI) is a major cause of early graft dysfunction after kidney transplantation, particularly in recipients of high-risk donor kidneys prone to ischemia-reperfusion injury. However, the cellular mechanisms dictating whether injury resolves or progresses to fibrosis remain unclear. This study combines single-nucleus RNA sequencing and imaging mass cytometry (IMC) analysis of human kidney allograft biopsies collected within eight weeks posttransplant, stratified by long-term functional outcomes. Grafts that recovered function were enriched in regenerative proximal tubular (PT) cells co-expressing PROM1, CD24, and injury markers, consistent with scattered tubular cells (STCs). In contrast, non-recovering grafts contained a unique subpopulation of transitional proximal tubule cells (tPT4) characterized by dedifferentiation, loss of epithelial identity, and acquisition of fibroblast-like features. Fibroblast trajectory analysis revealed a profibrotic lineage, progressing from stromal progenitors to myofibroblasts, exclusive to nonrecovery grafts. Immune profiling showed divergent macrophage (MΦ) polarization, with reparative MΦ2 cells and regulatory dendritic cell (DC)-like signatures in recovering grafts, versus inflammatory MΦ1 and pro-fibrotic DCs in non-recovery. IMC confirmed spatial colocalization of injured tubules, activated fibroblasts, and immune cells in fibrotic regions, validated in an independent cohort. Functional assays demonstrated that ischemic epithelial injury activated monocyte-derived MΦs with mixed inflammatory/reparative profiles and induced fibroblast-related gene expression, while PAX8 knockdown impaired epithelial proliferation and promoted pro-inflammatory signaling. These findings reveal epithelial cell plasticity as a central driver of divergent repair outcomes following renal transplant AKI and highlight epithelial-immune-stromal crosstalk as a therapeutic target to promote recovery and prevent chronic graft injury.

One Sentence Summary

Single-cell and spatial mapping of human kidney transplants reveal regenerative and fibrotic cell programs across tubular, immune, and stromal compartments that determine whether acute injury resolves or progresses to chronic allograft injury.

Monitoring Macrophage Polarization in Infectious Disease, Lesson From SARS-CoV-2 Infection

The concept of macrophage polarization has been largely used in human diseases to define a typology of activation of myeloid cells reminiscent of lymphocyte functional subsets. In COVID-19, several studies have investigated myeloid compartment dysregulation and macrophage polarization as an indicator of disease prognosis and monitoring. SARS-CoV-2 induces an in vitro activation state in monocytes and macrophages that does not match the polarization categories in most studies. In COVID-19 patients, monocytes and macrophages are activated but they do not show a polarization profile. Therefore, the investigation of polarization under basic conditions was not relevant to assess monocyte and macrophage activation. The analysis of monocytes and macrophages with high-throughput methods has allowed the identification of new functional subsets in the context of COVID-19. This approach proposes an innovative stratification of myeloid cell activation. These new functional subsets of myeloid cells would be better biomarkers to assess the risk of complications in COVID-19, reserving the concept of polarization for pharmacological programme evaluation. This review reappraises the polarization of monocytes and macrophages in viral infections, particularly in COVID-19.

Identification and Experimental Validation of NETosis-Mediated Abdominal Aortic Aneurysm Gene Signature Using Multi-omics, Machine Learning, and Mendelian Randomization

Abdominal aortic aneurysm (AAA) is a life-threatening disorder with limited therapeutic options. Neutrophil extracellular traps (NETs) are formed by a process known as "NETosis" that has been implicated in AAA pathogenesis, yet the roles and prognostic significance of NET-related genes in AAA remain poorly understood. This study aimed to identify key AAA- and NET-related genes (AAA-NETs-RGs), elucidate their potential mechanisms in contributing to AAA, and explore potential therapeutic compounds for AAA therapy. Through bioinformatics analysis of multiomics and machine learning, we identified six AAA-NETs-RGs: DUSP26, FCN1, MTHFD2, GPRC5C, SEMA4A, and CCR7, which exhibited strong diagnostic potential for predicting AAA progression, were significantly enriched in pathways related to cytokine-cytokine receptor interaction and chemokine signaling. Immune infiltration analysis revealed a causal association between AAA-NETs-RGs and immune cell infiltration. Cell-cell communication analysis indicated that AAA-NETs-RGs predominantly function in smooth muscle cells, B cells, T cells, and NK cells, primarily through cytokine and chemokine signaling. Gene profiling revealed that CCR7 and MTHFD2 exhibited the most significant upregulation in AAA patients compared to non-AAA controls, as well as in in vitro AAA models. Notably, genetic depletion of CCR7 and MTHFD2 strongly inhibited Ang II-induced phenotypic switching, functional impairment, and senescence in vascular smooth muscle cells (VSMCs). Based on AAA-NETs-RGs, molecular docking analysis combined with the Connectivity Map (CMap) database identified mirdametinib as a potential therapeutic agent for AAA. Mirdametinib effectively alleviated Ang II-induced phenotypic switching, biological dysfunction, and senescence. These findings provide valuable insights into understanding the pathophysiology of AAA and highlight promising therapeutic strategies targeting AAA-NETs-RGs.

Identification and validation of immune-related biomarkers and polarization types of macrophages in keloid based on bulk RNA-seq and single-cell RNA-seq analysis

INTRODUCTION

Keloids are a common complication that occurs after injury. The pathogenesis of this disease remains unknown. Therefore, identifying immune-related biomarkers and macrophage polarization types in keloids can provide new insights into their treatment.

METHODS

In this study, keloid-related bulk RNA-seq data (GSE83286, GSE212954, GSE92566, and GSE90051) were obtained from the Gene Expression Omnibus (GEO) database. The datasets GSE83286, GSE212964, and GSE92566 were combined to form a training set, while GSE90051 was utilized as an external validation set. Differentially expressed genes (DEGs) were detected by comparing keloid and normal samples within the training set. Differentially expressed immune-related genes (DIRGs) were then determined by intersecting the DEGs with immune-related genes (IRGs). Based on the protein-protein interaction (PPI) network, the top 40 DIRGs were selected for further analyses. Weighted Gene Co-expression Network Analysis (WGCNA), in conjunction with three machine learning techniques - least absolute shrinkage and selection operator (LASSO), support vector machine-recursive feature elimination (SVM-RFE), and random forest (RF) - employed to identify biomarkers. Subsequently, a nomogram model was constructed and validated. Single-cell RNA (scRNA) analysis was used to examine the expression of biomarkers at the cell-type level. Furthermore, since keloid is a chronic inflammatory disease and the abnormal polarization of macrophages is essential for the occurrence of this kind of disease, in this study we also endeavor to elucidate the state of macrophage polarization dysregulation within keloid, with the anticipation of generating novel concepts for the treatment of keloid. Finally, western blot (WB) and immunofluorescence (IF) analyses were carried out to confirm the expression levels of the biomarkers.

RESULTS

A total of 740 DEGs were identified in the training set, comprising 331 up-regulated genes and 409 down-regulated genes. After intersecting with the IRGs, 73 DIRGs were obtained. Subsequently, the top 40 DIRGs were chosen for further analysis. Eventually, two biomarkers, namely BMP1 and IL1R1, were identified through WGCNA and the three machine learning methods. Their expression levels were then verified by single-cell analysis, WB, and IF analysis. Additionally, it was found that the number of M2 macrophages significantly increased, while the number of M1 macrophages decreased in keloids compared to normal samples.

CONCLUSION

BMP1 and IL1R1 might function as novel biomarkers and potential therapeutic targets for keloid treatment. Moreover, upregulating M1 macrophages and downregulating M2 macrophages could represent a promising approach for the treatment of keloids.

Bioinformatic analysis of serpina1 expression in papillary thyroid carcinoma and its potential association with Hashimoto's thyroiditis

PURPOSE

Previous studies have suggested that SERPINA1 may promote a better prognosis in papillary thyroid carcinoma (PTC) along with Hashimoto's thyroiditis (HT). This study aims to further explore the role of the SERPINA1 gene in PTC and its relationship with HT using multiple databases.

METHODS

Transcriptomic data from The Cancer Genome Atlas (TCGA) were utilized to analyze differences in SERPINA1 expression between PTC patients with and without HT. The expression levels of SERPINA1 in tumor tissues and its association with tumor characteristics were assessed using the Wilcoxon test across both patient groups. The impact of SERPINA1 expression on immune cell infiltration in PTC was evaluated using the CIBERSORT tool. Single-cell transcriptomic data from the Gene Expression Omnibus (GEO) were further analyzed to identify SERPINA1-expressing subpopulations based on Thyroid Differentiation Score (TDS) and pseudotime analysis. Gene Set Variation Analysis (GSVA) was employed to characterize pathways associated with SERPINA1, inferring its potential functions. Finally, CellChat was used to investigate key ligand-receptor interactions between SERPINA1-positive subpopulations and other cell types.

RESULTS

TCGA data analysis reveals that, compared to normal thyroid tissue, the transcriptional level of SERPINA1 is significantly elevated in PTC tissues. Moreover, the expression of SERPINA1 is closely linked to certain clinical pathological features of PTC and the infiltration of immune cells in the tumor microenvironment. Single-cell transcriptome analysis reveals that SERPINA1 is primarily expressed in thyrocytes and myeloid cells. In thyrocytes, SERPINA1 is associated with complement-related proteins (e.g., C3, CD55). In poorly differentiated thyrocytes, it is linked to protease inhibitors and epithelial-mesenchymal transition (EMT) pathways, while in moderately differentiated thyrocytes, it associates with apolipoproteins APOE and APOC1. In macrophages, SERPINA1 is highly expressed in HT-associated macrophages and unpolarized macrophages, correlating with inflammation and extracellular matrix regulation pathways. Cell-cell interaction analysis indicates that SERPINA1-positive cells interact with other cells in the tumor microenvironment through macrophage migration inhibitory factor (MIF) and fibronectin 1 (FN1).

CONCLUSION

Compared to normal thyroid tissue or cells, the expression level of SERPINA1 is elevated in PTC. In cancer cells, SERPINA1 may be associated with the complement system and complement regulator functions. In poorly differentiated thyrocytes, SERPINA1 may primarily function as a protease inhibitor and is closely related to FN1. In moderately differentiated thyrocytes, SERPINA1 is associated with apolipoproteins. In unpolarized macrophages, the function of SERPINA1 may be to act as a serine protease inhibitor, participating in the remodeling of the extracellular matrix. In macrophages within an HT environment, the elevated expression of SERPINA1 may serve as a protective mechanism to limit inflammation. In the tumor microenvironment coexisting with HT, SERPINA1 outside the tumor cells may enter the tumor cells through lipid metabolism pathways. The potential role of SERPINA1 in PTC progression is complex, and the findings of this study require further validation.

The role and research progress of tumor-associated macrophages in cervical cancer

Tumor-associated macrophages (TAMs) are important immune cells in the tumor micro-environment (TME) and play a key role in the occurrence and development of cervical cancer. Besides, targeting TAMs can significantly inhibit cervical cancer tumor growth, invasion, metastasis, and angiogenesis as well as affect immune regulation. This review summarizes the correlation between TAM and tumors, the mechanism of action of TAM in cervical cancer, and the potential application of TAM in the treatment of cervical cancer. Therefore, this study may provide new ideas and targets for the development of further treatment strategies for cervical cancer patients.

Innate immunity champions: The diverse functions of macrophages

Macrophages are instrumental in maintaining tissue homeostasis, modulating inflammation, and driving regeneration. The advent of omics techniques has led to the identification of numerous tissue-specific macrophage subtypes, thereby introducing the concept of the "macrophage niche". This paradigm underscores the ability of macrophages to adapt their functions based on environmental cues, such as tissue-specific signals. This adaptability is closely linked to their metabolic states, which are crucial for their function and role in health and disease. Macrophage metabolism is central to their ability to switch between proinflammatory and anti-inflammatory states. In this regard, environmental factors, including the extracellular matrix, cellular interactions, and microbial metabolites, profoundly influence macrophage behavior. Moreover, diet and gut microbiota significantly impact macrophage function, with nutrients and microbial metabolites influencing their activity and contributing to conditions like inflammatory bowel disease. Targeting specific macrophage functions and their metabolic processes is leading to the development of novel treatments for a range of chronic inflammatory conditions. The exploration of macrophage biology enriches our understanding of immune regulation and holds the promise of innovative approaches to managing diseases marked by inflammation and immune dysfunction, offering a frontier for scientific and clinical advancement.

Compromised C3b-VSIG4 axis between decidual NK cells and macrophages contributes to recurrent spontaneous abortion

NK cells and macrophages constitute the predominant immune cell subsets in the decidua during the first trimester of pregnancy, with macrophages typically adopting an anti-inflammatory phenotype. Conversely, in the third trimester, macrophages undergo a shift towards a pro-inflammatory phenotype concurrent with a reduction in NK cell numbers. The direct regulatory impact of NK cells on macrophage phenotype remains poorly explored. In our investigation, we observed that ICAM1+ macrophages stimulate the expression of intracellular C3 in LFA1+ decidual NK cells. Notably, Cathepsin W within NK cells exhibit the potential to generate active C3b fragments, effectively inhibit the proinflammatory phenotype of macrophages by binding to VSIG4. Our study unveils a direct regulatory mechanism orchestrated by decidual NK cells over macrophages, providing a potential pathogenic explanation for recurrent spontaneous abortion.

Multi-omics evaluation of the prognostic value and immune signature of FCN1 in pan-cancer and its relationship with proliferation and apoptosis in acute myeloid leukemia

Background

The FCN1 gene encodes the ficolin-1 protein, implicated in the pathogenesis of various diseases, though its precise role in tumorigenesis remains elusive. This study aims to elucidate the prognostic significance, immune signature, and treatment response associated with FCN1 across diverse cancer types.

Methods

Employing multi-omics data, we conducted a comprehensive assessment, encompassing tissue-specific and single-cell-specific expression disparities, pan-cancer expression patterns, epigenetic modifications affecting FCN1 expression, and the immune microenvironment. Our investigation primarily focused on the clinical prognostic attributes, immune profiles, potential molecular mechanisms, and candidate therapeutic agents concerning FCN1 and acute myeloid leukemia (AML). Additionally, in vitro experiments were performed to scrutinize the impact of FCN1 knockdown on cell proliferation, apoptosis, and cell cycle dynamics within the AML cell line U937 and NB4.

Results

FCN1 expression exhibits widespread dysregulation across various cancers. Through both univariate and multivariate Cox regression analyses, FCN1 has been identified as an independent prognostic indicator for AML. Immunological investigations elucidate FCN1's involvement in modulating inflammatory responses within the tumor microenvironment and its correlation with treatment efficacy. Remarkably, the deletion of FCN1 influences the proliferation, apoptosis, and cell cycle dynamics of U937 cells and NB4 cells.

Conclusion

These findings underscore FCN1 as a promising pan-cancer biomarker indicative of macrophage infiltration, intimately linked with the tumor microenvironment and treatment responsiveness, and pivotal for cellular mechanisms within AML cell lines.

FPR1, as a Potential Biomarker of Diagnosis and Infliximab Therapy Responses for Crohn's Disease, is Related to Disease Activity, Inflammation and Macrophage Polarization

Purpose

Crohn's disease (CD) represents a multifaceted inflammatory gastrointestinal condition, with a profound significance placed on unraveling its molecular pathways to enhance both diagnostic capabilities and therapeutic interventions. This study focused on identifying a robust macrophage-related signatures (MacroSig) for diagnosing CD, emphasizing the role of FPR1 in macrophage polarization and its implications in CD.

Patients and Methods

Expression profiles from intestinal biopsies and macrophages of 1804 CD patients were retrieved from the Gene Expression Omnibus (GEO). Utilizing CIBERSORTx, differential expression analysis, and weighted correlation network analysis to to identify macrophage-related genes (MRGs). By unsupervised clustering, distinct clusters of CD were identified. Potential biomarkers were identified via using four machine learning algorithms, leading to the establishment of MacroSig which combines insights from 12 machine learning algorithms. Furthermore, the expression of FPR1 was verified in intestinal biopsies of CD patients and two murine experimental colitis models. Finally, we further explored the role of FPR1 in macrophage polarization through single-cell analysis as well as through the study of RAW264.7 cells and peritoneal macrophages.

Results

Two distinct clusters with differential levels of macrophage infiltration and inflammation were identified. The MacroSig, which included FPR1 and LILRB2, exhibited high diagnostic accuracy and outperformed existing biomarkers and signatures. Clinical analysis demonstrated a strong correlation of FPR1 with disease activity, endoscopic inflammation status, and response to infliximab treatment. The expression levels of FPR1 were validated in our CD cohort by immunohistochemistry and confirmed in two colitis mouse models. Single-cell analysis indicated that FPR1 is predominantly expressed in macrophages and monocytes. In vitro studies demonstrated that FPR1 was upregulated in M1 macrophages, and its activation promoted M1 polarization.

Conclusion

We developed a promising diagnostic signature for CD, and targeting FPR1 to modulate macrophage polarization may represent a novel therapeutic strategy.

Investigating cellular similarities and differences between upper tract urothelial carcinoma and bladder urothelial carcinoma using single-cell sequencing

Background

Upper tract urothelial carcinoma (UTUC) and bladder urothelial carcinoma (BLCA) both originate from uroepithelial tissue, sharing remarkably similar clinical manifestations and therapeutic modalities. However, emerging evidence suggests that identical treatment regimens may lead to less favorable outcomes in UTUC compared to BLCA. Therefore, it is imperative to explore molecular processes of UTUC and identify biological differences between UTUC and BLCA.

Methods

In this study, we performed a comprehensive analysis using single-cell RNA sequencing (scRNA-seq) on three UTUC cases and four normal ureteral tissues. These data were combined with publicly available datasets from previous BLCA studies and RNA sequencing (RNA-seq) data for both cancer types. This pooled analysis allowed us to delineate the transcriptional differences among distinct cell subsets within the microenvironment, thus identifying critical factors contributing to UTUC progression and phenotypic differences between UTUC and BLCA.

Results

scRNA-seq analysis revealed seemingly similar but transcriptionally distinct cellular identities within the UTUC and BLCA ecosystems. Notably, we observed striking differences in acquired immunological landscapes and varied cellular functional phenotypes between these two cancers. In addition, we uncovered the immunomodulatory functions of vein endothelial cells (ECs) in UTUC, and intercellular network analysis demonstrated that fibroblasts play important roles in the microenvironment. Further intersection analysis showed that MARCKS promote UTUC progression, and immunohistochemistry (IHC) staining revealed that the diverse expression patterns of MARCKS in UTUC, BLCA and normal ureter tissues.

Conclusion

This study expands our multidimensional understanding of the similarities and distinctions between UTUC and BLCA. Our findings lay the foundation for further investigations to develop diagnostic and therapeutic targets for UTUC.

The shared circulating diagnostic biomarkers and molecular mechanisms of systemic lupus erythematosus and inflammatory bowel disease

Background

Systemic lupus erythematosus (SLE) is a multi-organ chronic autoimmune disease. Inflammatory bowel disease (IBD) is a common chronic inflammatory disease of the gastrointestinal tract. Previous studies have shown that SLE and IBD share common pathogenic pathways and genetic susceptibility, but the specific pathogenic mechanisms remain unclear.

Methods

The datasets of SLE and IBD were downloaded from the Gene Expression Omnibus (GEO). Differentially expressed genes (DEGs) were identified using the Limma package. Weighted gene coexpression network analysis (WGCNA) was used to determine co-expression modules related to SLE and IBD. Pathway enrichment was performed using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis for co-driver genes. Using the Least AbsoluteShrinkage and Selection Operator (Lasso) regressionand Support Vector Machine-Recursive Feature Elimination (SVM-RFE), common diagnostic markers for both diseases were further evaluated. Then, we utilizedthe CIBERSORT method to assess the abundance of immune cell infiltration. Finally,we used the single-cell analysis to obtain the location of common diagnostic markers.

Results

71 common driver genes were identified in the SLE and IBD cohorts based on the DEGs and module genes. KEGG and GO enrichment results showed that these genes were closely associated with positive regulation of programmed cell death and inflammatory responses. By using LASSO regression and SVM, five hub genes (KLRF1, GZMK, KLRB1, CD40LG, and IL-7R) were ultimately determined as common diagnostic markers for SLE and IBD. ROC curve analysis also showed good diagnostic performance. The outcomes of immune cell infiltration demonstrated that SLE and IBD shared almost identical immune infiltration patterns. Furthermore, the majority of the hub genes were commonly expressed in NK cells by single-cell analysis.

Conclusion

This study demonstrates that SLE and IBD share common diagnostic markers and pathogenic pathways. In addition, SLE and IBD show similar immune cellinfiltration microenvironments which provides newperspectives for future treatment.

Exploring the common mechanism of vascular dementia and inflammatory bowel disease: a bioinformatics-based study

Objective

Emerging evidence has shown that gut diseases can regulate the development and function of the immune, metabolic, and nervous systems through dynamic bidirectional communication on the brain-gut axis. However, the specific mechanism of intestinal diseases and vascular dementia (VD) remains unclear. We designed this study especially, to further clarify the connection between VD and inflammatory bowel disease (IBD) from bioinformatics analyses.

Methods

We downloaded Gene expression profiles for VD (GSE122063) and IBD (GSE47908, GSE179285) from the Gene Expression Omnibus (GEO) database. Then individual Gene Set Enrichment Analysis (GSEA) was used to confirm the connection between the two diseases respectively. The common differentially expressed genes (coDEGs) were identified, and the STRING database together with Cytoscape software were used to construct protein-protein interaction (PPI) network and core functional modules. We identified the hub genes by using the Cytohubba plugin. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis were applied to identify pathways of coDEGs and hub genes. Subsequently, receiver operating characteristic (ROC) analysis was used to identify the diagnostic ability of these hub genes, and a training dataset was used to verify the expression levels of the hub genes. An alternative single-sample gene set enrichment (ssGSEA) algorithm was used to analyze immune cell infiltration between coDEGs and immune cells. Finally, the correlation between hub genes and immune cells was analyzed.

Results

We screened 167 coDEGs. The main articles of coDEGs enrichment analysis focused on immune function. 8 shared hub genes were identified, including PTPRC, ITGB2, CYBB, IL1B, TLR2, CASP1, IL10RA, and BTK. The functional categories of hub genes enrichment analysis were mainly involved in the regulation of immune function and neuroinflammatory response. Compared to the healthy controls, abnormal infiltration of immune cells was found in VD and IBD. We also found the correlation between 8 shared hub genes and immune cells.

Conclusions

This study suggests that IBD may be a new risk factor for VD. The 8 hub genes may predict the IBD complicated with VD. Immune-related coDEGS may be related to their association, which requires further research to prove.

Blockade of V-domain immunoglobulin suppressor of T-cell activation reprograms tumour-associated macrophages and improves efficacy of PD-1 inhibitor in gastric cancer

BACKGROUND AND AIMS

In gastric cancer, the response rate of programmed cell death protein-1 (PD-1) inhibitor is far from satisfactory, indicating additional nonredundant pathways might hamper antitumour immunity. V-domain immunoglobulin suppressor of T-cell activation (VISTA) has been reported in several malignancies as a novel immune-checkpoint. Nevertheless, the role of VISTA in gastric cancer still remains obscure. Our purpose is to explore the clinical significance and potential mechanism of VISTA in affecting gastric cancer patients' survival and immunotherapeutic responsiveness.

METHODS

Our study recruited eight independent cohorts with a total of 1403 gastric cancer patients. Immunohistochemistry, multiplex immunofluorescence, flow cytometry or intracellular flow cytometry, quantitative polymerase chain reaction, western blotting, fluorescence-activated cell sorting, magnetic-activated cell sorting, smart-seq2, in vitro cell co-culture and ex vivo tumour inhibition assays were applied to investigate the clinical significance and potential mechanism of VISTA in gastric cancer.

RESULTS

VISTA was predominantly expressed on tumour-associated macrophages (TAMs), and indicated poor clinical outcomes and inferior immunotherapeutic responsiveness. VISTA+ TAMs showed a mixed phenotype. Co-culture of TAMs and CD8+ T cells indicated that VISTA+ TAMs attenuated effective function of CD8+ T cells. Blockade of VISTA reprogrammed TAMs to a proinflammatory phenotype, reactivated CD8+ T cells and promoted apoptosis of tumour cells. Moreover, blockade of VISTA could also enhance the efficacy of PD-1 inhibitor, suggesting that blockade of VISTA might synergise with PD-1 inhibitor in gastric cancer.

CONCLUSIONS

Our data revealed that VISTA was an immune-checkpoint associated with immunotherapeutic resistance. Blockade of VISTA reprogrammed TAMs, promoted T-cell-mediated antitumour immunity, and enhanced efficacy of PD-1 inhibitor, which might have implications in the treatment of gastric cancer.

Novel tumor-associated macrophage populations and subpopulations by single cell RNA sequencing

Tumor-associated macrophages (TAMs) are present in almost all solid tumor tissues. 16They play critical roles in immune regulation, tumor angiogenesis, tumor stem cell activation, tumor invasion and metastasis, and resistance to therapy. However, it is unclear how TAMs perform these functions. With the application of single-cell RNA sequencing (scRNA-seq), it has become possible to identify TAM subpopulations associated with distinct functions. In this review, we discuss four novel TAM subpopulations in distinct solid tumors based on core gene signatures by scRNA-seq, including FCN1 +, SPP1 +, C1Q + and CCL18 + TAMs. Functional enrichment and gene expression in scRNA-seq data from different solid tumor tissues found that FCN1 + TAMs may induce inflammation; SPP1 + TAMs are potentially involved in metastasis, angiogenesis, and cancer cell stem cell activation, whereas C1Q + TAMs participate in immune regulation and suppression; And CCL18 + cells are terminal immunosuppressive macrophages that not only have a stronger immunosuppressive function but also enhance tumor metastasis. SPP1 + and C1Q + TAM subpopulations can be further divided into distinct populations with different functions. Meanwhile, we will also present emerging evidence highlighting the separating macrophage subpopulations associated with distinct functions. However, there exist the potential disconnects between cell types and subpopulations identified by scRNA-seq and their actual function.

Medicinal Plants, Phytochemicals and Regulation of the NLRP3 Inflammasome in Inflammatory Bowel Diseases: A Comprehensive Review

Ongoing research explores the underlying causes of ulcerative colitis and Crohn's disease. Many experts suggest that dysbiosis in the gut microbiota and genetic, immunological, and environmental factors play significant roles. The term "microbiota" pertains to the collective community of microorganisms, including bacteria, viruses, and fungi, that reside within the gastrointestinal tract, with a particular emphasis on the colon. When there is an imbalance or disruption in the composition of the gut microbiota, it is referred to as dysbiosis. Dysbiosis can trigger inflammation in the intestinal cells and disrupt the innate immune system, leading to oxidative stress, redox signaling, electrophilic stress, and inflammation. The Nod-like Receptor (NLR) Family Pyrin Domain Containing 3 (NLRP3) inflammasome, a key regulator found in immunological and epithelial cells, is crucial in inducing inflammatory diseases, promoting immune responses to the gut microbiota, and regulating the integrity of the intestinal epithelium. Its downstream effectors include caspase-1 and interleukin (IL)-1β. The present study investigated the therapeutic potential of 13 medicinal plants, such as Litsea cubeba, Artemisia anomala, Piper nigrum, Morus macroura, and Agrimonia pilosa, and 29 phytocompounds such as artemisitene, morroniside, protopine, ferulic acid, quercetin, picroside II, and hydroxytyrosol on in vitro and in vivo models of inflammatory bowel diseases (IBD), with a focus on their effects on the NLRP3 inflammasome. The observed effects of these treatments included reductions in IL-1β, tumor necrosis factor-alpha, IL-6, interferon-gamma, and caspase levels, and increased expression of antioxidant enzymes, IL-4, and IL-10, as well as regulation of gut microbiota. These effects could potentially provide substantial advantages in treating IBD with few or no adverse effects as caused by synthetic anti-inflammatory and immunomodulated drugs. However, additional research is necessary to validate these findings clinically and to develop effective treatments that can benefit individuals who suffer from these diseases.