The heterogeneity of tumor-associated macrophages and strategies to target it

Tumor-associated macrophages(TAMs)are emerging as targets for tumor therapy because of their primary role in promoting tumor progression.Several studies have been conducted to target TAMs by reducing their infiltration,depleting their numbers,and reversing their phenotypes to suppress tumor progression,leading to the development of drugs in preclinical and clinical trials.However,the heterogeneous characteristics of TAMs,including their ontogenetic and functional heterogeneity,limit their targeting.Therefore,in-depth exploration of the heterogeneity of TAMs,combined with immune checkpoint therapy or other therapeutic modalities could improve the efficiency of tumor treatment.This review focuses on the heterogeneous ontogeny and function of TAMs,as well as the current development of tumor therapies targeting TAMs and combination strategies.

Neutrophil peptide 1 accelerates the clearance of degenerative axons during Wallerian degeneration by activating macrophages after peripheral nerve crush injury

Macrophages play an important role in peripheral nerve regeneration,but the specific mechanism of regeneration is still unclear.Our preliminary findings indicated that neutrophil peptide 1 is an innate immune peptide closely involved in peripheral nerve regeneration.However,the mechanism by which neutrophil peptide 1 enhances nerve regeneration remains unclear.This study was designed to investigate the relationship between neutrophil peptide 1 and macrophages in vivo and in vitro in peripheral nerve crush injury.The functions of RAW 264.7 cells we re elucidated by Cell Counting Kit-8 assay,flow cytometry,migration assays,phagocytosis assays,immunohistochemistry and enzyme-linked immunosorbent assay.Axonal debris phagocytosis was observed using the CUBIC(Clear,Unobstructed Brain/Body Imaging Cocktails and Computational analysis)optical clearing technique during Wallerian degeneration.Macrophage inflammatory factor expression in different polarization states was detected using a protein chip.The results showed that neutrophil peptide 1 promoted the prolife ration,migration and phagocytosis of macrophages,and CD206 expression on the surfa ce of macrophages,indicating M2 polarization.The axonal debris clearance rate during Wallerian degeneration was enhanced after neutrophil peptide 1 intervention.Neutrophil peptide 1 also downregulated inflammatory factors interleukin-1α,-6,-12,and tumor necrosis factor-αin invo and in vitro.Thus,the results suggest that neutrophil peptide 1 activates macrophages and accelerates Wallerian degeneration,which may be one mechanism by which neutrophil peptide 1 enhances peripheral nerve regeneration.

Inhibition of M2 tumor-associated macrophages polarization by modulating the Wnt/β-catenin pathway as a possible liver cancer therapy method

The problem of liver cancer is becoming increasingly important due to the epi-demic of metabolic diseases and persistent high alcohol consumption.This deter-mines great attention to the development and improvement of methods for early diagnosis and treatment of liver cancer.Huang et al presented a study in the World Journal of Gastroenterology,in which they showed that the use of the traditional Chinese medicine Calculus bovis(CB)can suppress tumor growth in mice by inhibiting M2 tumor-associated macrophages(TAM)through modulating the activity of the Wnt/β-catenin pathway.The interaction of CB components with the Wnt/β-catenin pathway,M2 TAM polarization,and tumor dynamics were studied using network pharmacology,transcriptomics,and molecular docking.It is now generally accepted that the polarization of TAM and the differentiation of the functions of M1 and M2 phagocytes are of great importance for the progression of neoplasms.It is assumed that M2 TAM promote proliferation and migration of tumor cells.Attempts to medicinally influence the Wnt/β-catenin pathway in order to modulate phagocyte polarization now belong to one of the most promising areas of immunotherapy of oncological diseases.Undoubtedly,the work of the Chinese authors deserves attention and further development.

Sulfated Cyclocarya paliurus polysaccharides exert immunomodulatory potential on macrophages via Toll-like receptor 4 mediated MAPK/NF-κB signaling pathways

The biological activity of plant polysaccharides can be enhanced by sulfated modification.In this study,the immunomodulatory effect of sulfated Cyclocarya paliurus polysaccharides(SCP3)on macrophages RAW264.7 and its potential molecular mechanism were investigated.Results showed that SCP3 at 25-100μg/m L increased viability and improved phagocytosis of RAW264.7 cells.Meanwhile,SCP3 could activate mitogen-activated protein kinase(MAPK)and nuclear factor kappa B(NF-κB)signaling pathways,which increased the phosphorylation of Erk1/2,JNK,p38 and NF-κB p65,promoting secretion of cytokines tumor necrosis factorα(TNF-α),interleukin 6(IL-6)and nitric oxide(NO)as well as the production of reactive oxygen species(ROS).In addition,Toll-like receptor 4(TLR4)receptor inhibitors were able to block the production of NO and TNF-αby SCP3-stimulated macrophages.Based on Western blot analysis and validation using specific inhibitors against MAPK and NF-κB signaling pathways,the results demonstrated that SCP3 induced macrophages activation and enhanced TNF-αand NO production via TLR4-mediated MAPK and NF-κB pathways.In summary,SCP3 has significant immunomodulatory potential.The underlying molecular mechanism was that SCP3 activates macrophages via TLR4 receptors to promote ROS production,which in turn activates the downstream MAPK/NF-κB signaling pathway and then increases the secretion levels of cytokines and NO.

Anti-tumor efficacy of Calculus bovis: Suppressing liver cancer by targeting tumor-associated macrophages

Despite significant advances in our understanding of the molecular pathogenesis of liver cancer and the availability of novel pharmacotherapies,liver cancer remains the fourth leading cause of cancer-related mortality worldwide.Tumor relapse,resistance to current anti-cancer drugs,metastasis,and organ toxicity are the major challenges that prevent considerable improvements in patient survival and quality of life.Calculus bovis(CB),an ancient Chinese medicinal drug,has been used to treat various pathologies,including stroke,convulsion,epilepsy,pain,and cancer.In this editorial,we discuss the research findings recently published by Huang et al on the therapeutic effects of CB in inhibiting the development of liver cancer.Utilizing the comprehensive transcriptomic analyses,in vitro experiments,and in vivo studies,the authors demonstrated that CB treatment inhibits the tumor-promoting M2 phenotype of tumor-associated macrophages via downregulating Wnt pathway.While multiple studies have been performed to explore the molecular mechanisms regulated by CB,this study uniquely shows its role in modulating the M2 phenotype of macrophages present within the tumor microenvironment.This study opens new avenues of future investigations aimed at investigating this drug’s efficacy in various mouse models including the effects of combination therapy,and against drug-resistant tumors.

Interplay between mesenchymal stem cells and macrophages:Promoting bone tissue repair

The repair of bone tissue damage is a complex process that is well-orchestrated in time and space,a focus and difficulty in orthopedic treatment.In recent years,the success of mesenchymal stem cells(MSCs)-mediated bone repair in clinical trials of large-area bone defects and bone necrosis has made it a candidate in bone tissue repair engineering and regenerative medicine.MSCs are closely related to macrophages.On one hand,MSCs regulate the immune regulatory function by influencing macrophages proliferation,infiltration,and phenotype polarization,while also affecting the osteoclasts differentiation of macrophages.On the other hand,macrophages activate MSCs and mediate the multilineage differentiation of MSCs by regulating the immune microenvironment.The cross-talk between MSCs and macrophages plays a crucial role in regulating the immune system and in promoting tissue regeneration.Making full use of the relationship between MSCs and macrophages will enhance the efficacy of MSCs therapy in bone tissue repair,and will also provide a reference for further application of MSCs in other diseases.

Research progress of tumor-associated macrophages in immune checkpoint inhibitor tolerance in colorectal cancer

The relevant mechanism of tumor-associated macrophages(TAMs)in the treatment of colorectal cancer patients with immune checkpoint inhibitors(ICIs)is discussed,and the application prospects of TAMs in reversing the treatment tolerance of ICIs are discussed to provide a reference for related studies.As a class of drugs widely used in clinical tumor immunotherapy,ICIs can act on regulatory molecules on cells that play an inhibitory role-immune checkpoints-and kill tumors in the form of an immune response by activating a variety of immune cells in the immune system.The sensitivity of patients with different types of colorectal cancer to ICI treatment varies greatly.The phenotype and function of TAMs in the colorectal cancer microenvironment are closely related to the efficacy of ICIs.ICIs can regulate the phenotypic function of TAMs,and TAMs can also affect the tolerance of colorectal cancer to ICI therapy.TAMs play an important role in ICI resistance,and making full use of this target as a therapeutic strategy is expected to improve the immunotherapy efficacy and prognosis of patients with colorectal cancer.

Interactions between myoblasts and macrophages under high glucose milieus result in inflammatory response and impaired insulin sensitivity

BACKGROUND Skeletal muscle handles about 80% of insulin-stimulated glucose uptake and become the major organ occurring insulin resistance(IR).Many studies have confirmed the interactions between macrophages and skeletal muscle regulated the inflammation and regeneration of skeletal muscle.However,despite of the decades of research,whether macrophages infiltration and polarization in skeletal muscle under high glucose(HG)milieus results in the development of IR is yet to be elucidated.C2C12 myoblasts are well-established and excellent model to study myogenic regulation and its responses to stimulation.Further exploration of macrophages'role in myoblasts IR and the dynamics of their infiltration and polarization is warranted.AIM To evaluate interactions between myoblasts and macrophages under HG,and its effects on inflammation and IR in skeletal muscle.METHODS We detected the polarization status of macrophages infiltrated to skeletal muscles of IR mice by hematoxylin and eosin and immunohistochemical staining.Then,we developed an in vitro co-culture system to study the interactions between myoblasts and macrophages under HG milieus.The effects of myoblasts on macrophages were explored through morphological observation,CCK-8 assay,Flow Cytometry,and enzyme-linked immunosorbent assay.The mediation of macrophages to myogenesis and insulin sensitivity were detected by morphological observation,CCK-8 assay,Immunofluorescence,and 2-NBDG assay.RESULTS The F4/80 and co-localization of F4/80 and CD86 increased,and the myofiber size decreased in IR group(P<0.01,g=6.26).Compared to Mc group,F4/80+CD86+CD206-cells,tumor necrosis factor-α(TNFα),inerleukin-1β(IL-1β)and IL-6 decreased,and IL-10 increased in McM group(P<0.01,g>0.8).In McM+HG group,F4/80+CD86+CD206-cells,monocyte chemoattractant protein 1,TNFα,IL-1βand IL-6 were increased,and F4/80+CD206+CD86-cells and IL-10 were decreased compared with Mc+HG group and McM group(P<0.01,g>0.8).Compered to M group,myotube area,myotube number and E-MHC were increased in MMc group(P<0.01,g>0.8).In MMc+HG group,myotube area,myotube number,E-MHC,GLUT4 and glucose uptake were decreased compared with M+HG group and MMc group(P<0.01,g>0.8).CONCLUSION Interactions between myoblasts and macrophages under HG milieus results in inflammation and IR,which support that the macrophage may serve as a promising therapeutic target for skeletal muscle atrophy and IR.

Macrophages:Key players in diabetic wound healing

In this editorial,we discuss the article by Wen et al published.Diabetic foot ulcers are prevalent and serious complications of diabetes,significantly impacting patients’quality of life and often leading to disability or death,thereby placing a heavy burden on society.Effective diabetic wound healing is hindered by an imbalance in macrophage polarization;many macrophages fail to transition from the pro-inflammatory M1 phenotype to the anti-inflammatory M2 phenotype,which is crucial for tissue remodelling and repair.The wound healing process is both dynamic and complex.Healthy M1 macrophages,which have strong phagocytic abilities,are vital during the inflammatory phase of diabetic wound healing.However,the failure to transition to M2 macrophages during the proliferative phase hinders wound healing.We anticipate the development of new therapies that can repair damaged M1 macrophages during the inflammatory phase and promote M2 macrophage polarization during the proliferative phase,thereby enhancing the overall healing process.

Effects of interleukin-10 treated macrophages on bone marrow mesenchymal stem cells via signal transducer and activator of transcription 3 pathway

BACKGROUND Alveolar bone defects caused by inflammation are an urgent issue in oral implant surgery that must be solved.Regulating the various phenotypes of macrophages to enhance the inflammatory environment can significantly affect the progression of diseases and tissue engineering repair process.AIM To assess the influence of interleukin-10(IL-10)on the osteogenic differentiation of bone marrow mesenchymal stem cells(BMSCs)following their interaction with macrophages in an inflammatory environment.METHODS IL-10 modulates the differentiation of peritoneal macrophages in Wistar rats in an inflammatory environment.In this study,we investigated its impact on the proliferation,migration,and osteogenesis of BMSCs.The expression levels of signal transducer and activator of transcription 3(STAT3)and its activated form,phos-phorylated-STAT3,were examined in IL-10-stimulated macrophages.Subsequently,a specific STAT3 signaling inhibitor was used to impede STAT3 signal activation to further investigate the role of STAT3 signaling.RESULTS IL-10-stimulated macrophages underwent polarization to the M2 type through substitution,and these M2 macrophages actively facilitated the osteogenic differentiation of BMSCs.Mechanistically,STAT3 signaling plays a crucial role in the process by which IL-10 influences macrophages.Specifically,IL-10 stimulated the activation of the STAT3 signaling pathway and reduced the macrophage inflammatory response,as evidenced by its diminished impact on the osteogenic differentiation of BMSCs.CONCLUSION Stimulating macrophages with IL-10 proved effective in improving the inflammatory environment and promoting the osteogenic differentiation of BMSCs.The IL-10/STAT3 signaling pathway has emerged as a key regulator in the macrophage-mediated control of BMSCs’osteogenic differentiation.

Fasudil-modified macrophages reduce inflammation and regulate the immune response in experimental autoimmune encephalomyelitis

Multiple sclerosis is characterized by demyelination and neuronal loss caused by inflammatory cell activation and infiltration into the central nervous system.Macrophage polarization plays an important role in the pathogenesis of experimental autoimmune encephalomyelitis,a traditional experimental model of multiple sclerosis.This study investigated the effect of Fasudil on macrophages and examined the therapeutic potential of Fasudil-modified macrophages in experimental autoimmune encephalomyelitis.We found that Fasudil induced the conversion of macrophages from the pro-inflammatory M1 type to the anti-inflammatory M2 type,as shown by reduced expression of inducible nitric oxide synthase/nitric oxide,interleukin-12,and CD16/32 and increased expression of arginase-1,interleukin-10,CD14,and CD206,which was linked to inhibition of Rho kinase activity,decreased expression of toll-like receptors,nuclear factor-κB,and components of the mitogen-activated protein kinase signaling pathway,and generation of the pro-inflammatory cytokines tumor necrosis factor-α,interleukin-1β,and interleukin-6.Crucially,Fasudil-modified macrophages effectively decreased the impact of experimental autoimmune encephalomyelitis,resulting in later onset of disease,lower symptom scores,less weight loss,and reduced demyelination compared with unmodified macrophages.In addition,Fasudil-modified macrophages decreased interleukin-17 expression on CD4^(+)T cells and CD16/32,inducible nitric oxide synthase,and interleukin-12 expression on F4/80^(+)macrophages,as well as increasing interleukin-10 expression on CD4^(+)T cells and arginase-1,CD206,and interleukin-10 expression on F4/80^(+)macrophages,which improved immune regulation and reduced inflammation.These findings suggest that Fasudil-modified macrophages may help treat experimental autoimmune encephalomyelitis by inducing M2 macrophage polarization and inhibiting the inflammatory response,thereby providing new insight into cell immunotherapy for multiple sclerosis.

Atherosis-associated lnc_000048 activates PKR to enhance STAT1-mediated polarization of THP-1 macrophages to M1 phenotype

Our previous study has demonstrated that lnc_000048 is upregulated in large-artery atherosclerotic stroke and promotes atherosclerosis in ApoE^(-/-)mice.However,little is known about the role of lnc_000048 in classically activated macrophage(M1)polarization.In this study,we established THP-1-derived testing state macrophages(M0),M1 macrophages,and alternately activated macrophages(M2).Real-time fluorescence quantitative PCR was used to verify the expression of marker genes and the expression of lnc_000048 in macrophages.Flow cytometry was used to detect phenotypic proteins(CD11b,CD38,CD80).We generated cell lines with lentivirus-mediated upregulation or downregulation of lnc_000048.Flow cytometry,western blot,and real-time fluorescence quantitative PCR results showed that down-regulation of lnc_000048 reduced M1 macrophage polarization and the inflammation response,while over-expression of lnc_000048 led to the opposite effect.Western blot results indicated that lnc_000048 enhanced the activation of the STAT1 pathway and mediated the M1 macrophage polarization.Moreover,catRAPID prediction,RNA-pull down,and mass spectrometry were used to identify and screen the protein kinase RNA-activated(PKR),then catRAPID and RPIseq were used to predict the binding ability of lnc_000048 to PKR.Immunofluorescence(IF)-RNA fluorescence in situ hybridization(FISH)double labeling was performed to verify the subcellular colocalization of lnc_000048 and PKR in the cytoplasm of M1 macrophage.We speculate that lnc_000048 may form stem-loop structure-specific binding and activate PKR by inducing its phosphorylation,leading to activation of STAT1 phosphorylation and thereby enhancing STAT1 pathway-mediated polarization of THP-1 macrophages to M1 and inflammatory factor expression.Taken together,these results reveal that the lnc_000048/PKR/STAT1 axis plays a crucial role in the polarization of M1 macrophages and may be a novel therapeutic target for atherosclerosis alleviation in stroke.

SWIR FluorescenceImaging In Vivo Monitoring and Evaluating Implanted M2 Macrophages in Skeletal Muscle Regeneration

Skeletal muscle has a robust regeneration ability that is impaired by severe injury,disease,and aging.resulting in a decline in skeletal muscle function.Therefore,improving skeletal muscle regeneration is a key challenge in treating skeletal muscle-related disorders.Owing to their significant role in tissue regeneration,implantation of M2 macrophages(M2MФ)has great potential for improving skeletal muscle regeneration.Here,we present a short-wave infrared(SWIR)fluorescence imaging technique to obtain more in vivo information for an in-depth evaluation of the skeletal muscle regeneration effect after M2MФtransplantation.SWIR fluorescence imaging was employed to track implanted M2MФin the injured skeletal muscle of mouse models.It is found that the implanted M2MФaccumulated at the injury site for two weeks.Then,SWIR fluorescence imaging of blood vessels showed that M2MФimplantation could improve the relative perfusion ratio on day 5(1.09±0.09 vs 0.85±0.05;p=0.01)and day 9(1.38±0.16 vs 0.95±0.03;p=0.01)post-injury,as well as augment the degree of skeletal muscle regencration on day 13 post-injury.Finally,multiple linear regression analyses determined that post-injury time and relative perfusion ratio could be used as predictive indicators to evaluate skeletal muscle regeneration.These results provide more in vivo details about M2MФin skeletal muscle regeneration and confirm that M2MФcould promote angiogenesis and improve the degree of skeletal muscle repair,which will guide the research and development of M2MФimplantation to improve skeletal muscle regeneration.

Effect of tubastatin A on NLRP3 inflammasome activation in macrophages under hypoxia/ reoxygenation conditions

BACKGROUND:There are currently no effective drugs to mitigate the ischemia/reperfusion injury caused by fluid resuscitation after hemorrhagic shock(HS).The aim of this study was to explore the potential of the histone deacetylase 6(HDAC6)-specific inhibitor tubastatin A(TubA)to suppress nucleotide-binding oligomerization domain-like receptor protein 3(NLRP3)inflammasome activation in macrophages under hypoxia/reoxygenation(H/R)conditions.METHODS:The viability of RAW264.7 cells subjected to H/R after treatment with different concentrations of TubA was assessed using a cell-counting kit-8(CCK8)assay.Briefly,2.5μmol/L TubA was used with RAW264.7 cells under H/R condition.RAW264.7 cells were divided into three groups,namely the control,H/R,and TubA groups.The levels of reactive oxygen species(ROS)in the cells were detected using fluorescence microscopy.The protein expression of HDAC6,heat shock protein 90(Hsp90),inducible nitric oxide synthase(iNOS),NLRP3,gasdermin-D(GSDMD),Caspase-1,GSDMD-N,and Caspase-1 p20 was detected by western blotting.The levels of interleukin-1β(IL-1β)and IL-18 in the supernatants were detected using enzyme-linked immunosorbent assay(ELISA).RESULTS:HDAC6,Hsp90,and iNOS expression levels were significantly higher(P<0.01)in the H/R group than in the control group,but lower in the TubA group than in the H/R group(P<0.05).When comparing the H/R group to the control group,ROS levels were significantly higher(P<0.01),but significantly reduced in the TubA group(P<0.05).The H/R group had higher NLRP3,GSDMD,Caspase-1,GSDMD-N,and Caspase-1 p20 expression levels than the control group(P<0.05),however,the TubA group had significantly lower expression levels than the H/R group(P<0.05).IL-1βand IL-18 levels in the supernatants were significantly higher in the H/R group compared to the control group(P<0.01),but significantly lower in the TubA group compared to the H/R group(P<0.01).CONCLUSION:TubA inhibited the expression of HDAC6,Hsp90,and iNOS in macrophages subjected to H/R.This inhibition led to a decrease in the content of ROS in cells,which subsequently inhibited the activation of the NLRP3 inflammasome and the secretion of IL-1βand IL-18.

Global trends in publications regarding macrophages-related diabetic foot ulcers in the last two decades

BACKGROUND Diabetic foot ulcers(DFUs)are one of the most severe and popular complications of diabetes.The persistent non-healing of DFUs is the leading cause of amputation,which causes significant mental and financial stress to patients and their families.Macrophages are critical cells in wound healing and perform essential roles in all phases of wound healing.However,no studies have been carried out to systematically illustrate this area from a scientometric point of view.Although there have been some bibliometric studies on diabetes,reports focusing on the investigation of macrophages in DFUs are lacking.AIM To perform a bibliometric analysis to systematically assess the current state of research on macrophage-related DFUs.METHODS The publications of macrophage-related DFUs from January 1,2004,to December 31,2023,were retrieved from the Web of Science Core Collection on January 9,2024.Four different analytical tools:VOSviewer(v1.6.19),CiteSpace(v6.2.R4),HistCite(v12.03.07),and Excel 2021 were used for the scientometric research.RESULTS A total of 330 articles on macrophage-related DFUs were retrieved.The most published countries,institutions,journals,and authors in this field were China,Shanghai Jiao Tong University of China,Wound Repair and Regeneration,and Aristidis Veves.Through the analysis of keyword co-occurrence networks,historical direct citation networks,thematic maps,and trend topics maps,we synthesized the prevailing research hotspots and emerging trends in this field.CONCLUSION Our bibliometric analysis provides a comprehensive overview of macrophage-related DFUs research and insights into promising upcoming research.

The potential role of Gegen Qinlian decoction in the treatment of coronavirus disease 2019 based on network pharmacology and validation of lipopolysaccharide-induced macrophages

Background:Coronavirus disease 2019(COVID-19)is caused by severe acute respiratory syndrome coronavirus 2,which has led to deaths and currently lacks an efficient treatment.Despite studies suggesting the potential of the Gegen Qinlian decoction(GQD)in preventing COVID-19,comprehensive analyses of its anti-COVID-19 potential are still lacking.Methods:GQD treatment was evaluated for its efficacy in ameliorating the early stage(24 hours)of lipopolysaccharide(LPS)-induced cytokine storm in vivo.Additionally,target genes of GQD were co-analyzed with COVID-19 signature genes to identify key ingredients and their pathways.Validation was also conducted using an LPS-induced macrophage model.Results:GQD treatment effectively ameliorated the early stage of LPS-induced cytokine storm in vivo.Key ingredients such as quercetin were found to be involved in multiple pathways,including inflammation,immunity,oxidative stress,cell proliferation,and apoptosis,through the AGE-RAGE signaling pathway and IL-17 signaling pathway.In the LPS-induced macrophage model,quercetin inhibited macrophage polarization(M1)and the secretion of inflammatory factors(IL-6,TNF-α,IL-17A).Conclusions:Our results indicate that GQD can be utilized in the treatment of cytokine storm induced by COVID-19 and has the potential to treat COVID-19 by suppressing the COVID-19 signature genes and macrophage polarization.

Pig macrophages with site-specific edited CD163 decrease the susceptibility to infection with porcine reproductive and respiratory syndrome virus

Porcine reproductive and respiratory syndrome(PRRS)is recognized as one of the most infectious viral diseases of swine.Although Cluster of differentiation 163(CD163)is identified as an essential receptor for mediating PRRS virus(PRRSV)infection,the important residues involved in infection on CD163 are still unclear.Therefore,it is very important to identify these key residues to study the mechanism of PRRSV infection and to generate anti-PRRSV pigs.In this study,we first generated immortalized porcine alveolar macrophage(IPAM)cell lines harboring 40-residues(residues 523-562,including R561(arginine(R)at position 561))deletion of CD163.PRRSV infection experiments showed that these IPAM cell lines were completely resistant to PRRSV infection.We then generated cloned pigs carrying CD163-R561A(an arginine(R)to alanine(A)substitution at position 561 of CD163).PRRSV challenge experiments in porcine alveolar macrophages(PAMs)isolated from the CD163-R561A pigs showed significantly lower susceptibility to PRRSV than that of CD163-R561 PAMs.Through this study,we show that CD163523-562 contains essential residues for mediating PRRSV infection,and that CD163 R561 significantly contributes to PRRSV infection but is not essential for infection.These functional sites can therefore serve as new targets for understanding the mechanism of PRRSV infection.Furthermore,CD163-R561A pigs can be used as an important model for improving pig germplasm with resistance against PRRSV.

Adipose tissue macrophages:implications for obesity-associated cancer

Obesity is one of the most serious global health problems,with an incidence that increases yearly and coincides with the development of cancer.Adipose tissue macrophages(ATMs)are particularly important in this context and contribute to linking obesity-related inflammation and tumor progression.However,the functions of ATMs on the progression of obesity-associated cancer remain unclear.In this review,we describe the origins,phenotypes,and functions of ATMs.Subsequently,we summarize the potential mechanisms on the reprogramming of ATMs in the obesity-associated microenvironment,including the direct exchange of dysfunctional metabolites,inordinate cytokines and other signaling mediators,transfer of extracellular vesicle cargo,and variations in the gut microbiota and its metabolites.A better understanding of the properties and functions of ATMs under conditions of obesity will lead to the development of new therapeutic interventions for obesity-related cancer.

Effect of dual targeting procyanidins nanoparticles on metabolomics of lipopolysaccharide-stimulated inflammatory macrophages

Inflammation plays an important role in the occurrence and development of many inflammatory diseases.The purpose of this study was to evaluate the anti-inflammatory effect and metabolic behavior of the dual targeting procyanidins(PC)nanoparticles on lipopolysaccharide(LPS)-stimulated inflammatory macrophages by metabolomics method.The double-targeting PC nanoparticles could specifi cally target both the CD44 receptor and mitochondria,while the single targeting PC-loaded nanoparticles that could target the CD44 receptor on the surface of macrophages.The double-targeting PC nanoparticles had better inhibitory effect than single-targeting PC nanoparticles on the leakage of lactate dehydrogenase and reactive oxygen species overexpression induced by LPS.Amino acid metabolism,energy metabolism and purine metabolism were disordered in LPS-treated group,and metabolic pathway analysis indicated that the double-targeting PC nanoparticles reversed some of LPS impacts.The changes of these potential biomarkers and their corresponding pathways are helpful to further understand the mechanism of PC nanoparticles in alleviating inflammation,and promote their application in nutrition intervention.

ScRNA-seq reveals the correlation between M2 phenotype of tumorassociated macrophages and lymph node metastasis of breast cancer

The process of lymphatic metastasis was proved to be associated with podoplanin-expressing macrophages in breast cancer(BC).This study aimed to investigate the role of the M2 phenotype of tumor-associated macrophages and mine the key M2 macrophages-related genes for lymph node metastasis in BC.We downloaded the GSE158399 dataset from the Gene Expression Omnibus(GEO)database,which includes transcriptomic profiles of individual cells from primary tumors,negative lymph nodes(NLNs),and positive lymph nodes(PLNs)of breast cancer patients.The cell subsets were identified by clustering analysis after quality control of the scRNA-seq using Seurat.The activation and migration capability of M2 macrophages were evaluated with R package“GSVA”.The key M2 macrophages-related genes were screened from the differential expressed genes(DEGs)and M2 macrophages activation and migration gene sets collected from MSigDB database.Our analysis identified three main cell types in primary tumors,NLNs,and PLNs:basal cells,luminal cells,and immune cell subsets.The further cell type classification of immune cell subsets indicated M2 macrophages accumulation in NLs and PLs.The GSVA enrichment scores for activation and migration capability were increased significantly in M2 macrophages from primary tumors than NLNs and PLNs(pvalue<0.001).Seven M2 macrophages activation-related and 15 M2 macrophages migration-related genes were significantly up-regulated in primary tumors than NLNs and PLNs.The proportion and GSVA enrichment scores for activation and migration of M2 macrophages may be potential markers for lymph node metastasis in breast cancer.Our study demonstrated that twenty-two up-regulated mRNA may be possible therapeutic targets for lymph node metastasis in breast cancer.