Microglia, the main driver of neuroinflammation, play a central role in the initiation and exacerbation of various neurodegenerative diseases and are now considered a promising therapeutic target. Previous studies on ...Microglia, the main driver of neuroinflammation, play a central role in the initiation and exacerbation of various neurodegenerative diseases and are now considered a promising therapeutic target. Previous studies on in vitro human microglia and in vivo rodent models lacked scalability, consistency, or physiological relevance, which deterred successful therapeutic outcomes for the past decade. Here we review human blood monocyte-derived microglia-like cells as a robust and consistent approach to generate a patient-specific microglia-like model that can be used in extensive cohort studies for drug testing. We will highlight the strength and applicability of human blood monocyte-derived microglia-like cells to increase translational outcomes by reviewing the advantages of human blood monocyte-derived microglia-like cells in addressing patient heterogeneity and stratification, the basis of personalized medicine.展开更多
Monocyte-derived macrophages(MoMacs)are the most important effector cells that cause pulmonary fibrosis.However,the characteristics of MoMac differentiation in silicosis and the mechanisms by which MoMacs affect the p...Monocyte-derived macrophages(MoMacs)are the most important effector cells that cause pulmonary fibrosis.However,the characteristics of MoMac differentiation in silicosis and the mechanisms by which MoMacs affect the progression of pulmonary fibrosis remain unclear.Integration of single-cell and spatial transcriptomic analyses revealed that the silicosis niche was occupied by a subset of MoMacs,identified as Spp1hiMacs,which remain in an immature transitional state of differentiation during silicosis.This study investigated the mechanistic foundations of mitochondrial damage induced by the lipoprotein-associated phospholipase A2(Lp-PLA2,encoded by Pla2g7)–acyl-CoA:lysocardiolipin acyltransferase-1(ALCAT1)–cardiolipin(CL)signaling pathway,which interferes with Spp1hiMac differentiation.We demonstrated that in SiO_(2)-induced MoMacs,Lp-PLA2 induces abnormal CL acylation through the activation of ALCAT1,resulting in impaired mitochondrial localization of PINK1 and LC3B and mitochondrial autophagy defects.Simultaneously,lysosomal dysfunction causes the release of the lysosomal protein cathepsin B into the cytoplasm,which involves M1 and M2 macrophage polarization and the activation of proinflammatory and profibrotic pathways.Furthermore,we assessed the efficacy of the Lp-PLA2 inhibitor darapladib in ameliorating silica-induced pulmonary fibrosis in a murine model.Our findings enhance our understanding of silicosis pathogenesis and offer promising opportunities for developing targeted therapies to mitigate fibrotic progression and maintain lung function in affected individuals.展开更多
In this experiment Toll-like receptor expression pattern in monocytes and monocyte-derived macrophages by lipopolysaccharide （LPS） stimulation was examined. Jugular venous blood was collected from four Japanese calv...In this experiment Toll-like receptor expression pattern in monocytes and monocyte-derived macrophages by lipopolysaccharide （LPS） stimulation was examined. Jugular venous blood was collected from four Japanese calves, and the peripheral blood mononuclear cells （PBMCs） were isolated. The cells were directly used for collecting monocytes by magnetic cell sorting or cultured for 7 days to collect monocyte-derived macrophages in Repcell. Then we analyzed the mRNA expression pattern of TLRs and cytokines in monocytes and monocyte-derived macrophages after LPS stimulation for 24 h. LPS stimulation of both monocytes and monocyte-derived macrophages resulted in an increase in the levels of mRNA transcripts for TNF-α IL-6 and IL-8. Moreover, TNF-α and IL-6 mRNA expressions were significantly augmented by LPS stimulation in monocyte-derived macrophages. TLRs mRNA expressions were unchanged after LPS stimulation of monocytes, while TLRs mRNA expressions in monocyte-derived macrophages were complicated. TLR1, 3, 5, 8 and 10 were significantly decreased after LPS stimulation and there were no differences in the mRNA expressions of TLR2, 4, 6 and 7 between the groups of control and LPS stimulation. Besides, no expression of TLR9 was found. As antigen presenting cells, monocytes and monocyte-derived macrophages respond differently to LPS, so they may have different functions in the innate immune system.展开更多
Accumulating evidence suggests that the Thl immune .response induced by various antigens such as oxidized low density lipoprotein （ox-LDL） and heat shock proteins （HSPs） play a key role in the process of atheroscl...Accumulating evidence suggests that the Thl immune .response induced by various antigens such as oxidized low density lipoprotein （ox-LDL） and heat shock proteins （HSPs） play a key role in the process of atherosclerosis.1Dendritic cells （DCs） are the most potent antigen-presenting cells （APCs） in the body with the unique ability to initiate a primary immune response to certain antigens by the activation of ＂naive＂ T cells.2 The maturation of DC with the upregulation of costimulatory molecules such as CD83, CD40, CD86, and major histocompatibility complex （MHC） class molecules such as human leukocyte antigen （HLA）-DR, is required for DC to activate T cells. Pathologic studies have shown that immature DCs are present in normal arterial while abundant mature DCs clustered with T cells could be visualized in atherogenic vessels suggesting that DC 3 maturation is linked to the progression of atherosclerosls. Peroxisome proliferator-activated receptors （PPARs） a, one member of the family of PPARs, was found to have favorable effects on slowing the progression of atherosclerosis and reducing the risk of coronary heart disease in high-risk patients independent from their metabolism effects.4＇5 Furthermore, PPAR-α is also expressed on monocytes and monocyte-derived DCs.6 The effects of PPAR-α on DCs maturation and immune function remain unknown now, we therefore observed the effects of fenofibrate, a PPAR-α agonist, on the maturation and immune function of oxidized LDL-treated DCs in this study.展开更多
Dendritic cells （DCs） play a pivotal role in linking the innate immunity and acquired immunity in responses to pathogen. Non-human primates such as Chinese Rhesus Macaque （CRM） are the favorable models for preclin...Dendritic cells （DCs） play a pivotal role in linking the innate immunity and acquired immunity in responses to pathogen. Non-human primates such as Chinese Rhesus Macaque （CRM） are the favorable models for preclinical study of potential therapeutic drugs, vaccines and mechanisms of human diseases. However, the phenotypical characterization of monocyte-derived dendritic cells （MDDCs） from CRM has not been elucidated. Monocytes from CRM were cultured with GM-CSF and IL-4 in RPMI-1640. Six days later, these cells were differentiated with typical dendritical morphology. CDllc and DC-SIGN were highly expressed. The immature MDDCs expressed the low levels of CD25, CD80, CD83, moderate CD40, CD86, and high MHC. After stimulation, the mature MDDCs increased expression of mature molecules CD25 and CD83, co-stimulatory molecules such as CD80, CD86 and CD40, and kept a high level of MHC. The capacity of endocytosis decreased with maturation. The mature MDDCs have strong ability of inducing allogeneic T cell proliferation and producing IL-12. In conclusion, we have characterized the phenotype and ultimate function of MDDCs from CRM for the first time.展开更多
Naf1(Nef-associated factor 1)is a host protein that interacts with human immunodeficiency virus type 1(HIV-1)Nef protein.We and others have previously demonstrated that Naf1 restricts HIV-1 infection of T-lymphocytes....Naf1(Nef-associated factor 1)is a host protein that interacts with human immunodeficiency virus type 1(HIV-1)Nef protein.We and others have previously demonstrated that Naf1 restricts HIV-1 infection of T-lymphocytes.Myeloid cells are targets for HIV infection,but Naf1 expression in myeloid cells and whether it also regulates HIV infection in these cells are not yet identified.In this study,we found that Naf1 had a higher expression in CD14þmonocytes than in monocyte-derived dendritic cells(MDDCs),and its expression in both types of cells could be induced by HIV-1 gp120 glycoproteins or viral particles.Importantly,the expression of Naf1 restricted HIV-1 infection in monocytes and MDDCs.Functional investigation showed that both the constitutive and the induced expression of Naf1 inhibited NF-κB signaling in MDDCs and reduced the basal level or LPS(Lipopolysaccharide)-stimulated production of cytokines.Moreover,Naf1 reduced the expression of ICAM-1(intercellular cell adhesion molecule-1)on MDDCs and compromised their capacity to prime the activation of resting CD4^(+)T cells in co-culture.In light of the essential role of NF-κB signaling for HIV-1 transcription,Naf1-mediated inhibition of NF-κB signaling may hinder a robust viral replication in MDDCs and help maintain viral persistence.Furthermore,virus-induced Naf1 expression in MDDCs may diminish the cross-talk between DC(dendritic cell)and T cells,hence suppressing the activation of antiviral immune responses.Taken together,we identified the new function of Naf1 in myeloid cells.Those findings may facilitate the understanding for the host restriction of HIV-1 infection in myeloid cells.展开更多
Interactions between brain-resident and periph-eral infiltrated immune cells are thought to contribute to neuroplasticity after cerebral ischemia.However,con-ventional bulk sequencing makes it challenging to depict th...Interactions between brain-resident and periph-eral infiltrated immune cells are thought to contribute to neuroplasticity after cerebral ischemia.However,con-ventional bulk sequencing makes it challenging to depict this complex immune network.Using single-cell RNA sequencing,we mapped compositional and transcriptional features of peri-infarct immune cells.Microglia were the predominant cell type in the peri-infarct region,displaying a more diverse activation pattern than the typical pro-and anti-inflammatory state,with axon tract-associated micro-glia(ATMs)being associated with neuronal regeneration.Trajectory inference suggested that infiltrated monocyte-derived macrophages(MDMs)exhibited a gradual fate trajectory transition to activated MDMs.Inter-cellular crosstalk between MDMs and microglia orchestrated anti-inflammatory and repair-promoting microglia phenotypes and promoted post-stroke neurogenesis,with SOX2 and related Akt/CREB signaling as the underlying mechanisms.This description of the brain's immune landscape and its relationship with neurogenesis provides new insight into promoting neural repair by regulating neuroinflammatory responses.展开更多
BACKGROUND Serum small extracellular vesicles(sEVs)and their small RNA(sRNA)cargoes could be promising biomarkers for the diagnosis of liver injury.However,the dynamic changes in serum sEVs and their sRNA components d...BACKGROUND Serum small extracellular vesicles(sEVs)and their small RNA(sRNA)cargoes could be promising biomarkers for the diagnosis of liver injury.However,the dynamic changes in serum sEVs and their sRNA components during liver injury have not been well characterized.Given that hepatic macrophages can quickly clear intravenously injected sEVs,the effect of liver injury-related serum sEVs on hepatic macrophages deserves to be explored.AIM To identify the characteristics of serum sEVs and the sRNAs during liver injury and explore their effects on hepatic macrophages.METHODS To identify serum sEV biomarkers for liver injury,we established a CCL4-induced mouse liver injury model in C57BL/6 mice to simulate acute liver injury(ALI),chronic liver injury(CLI)and recovery.Serum sEVs were obtained and characterized by transmission electron microscopy and nanoparticle tracking analysis.Serum sEV sRNAs were profiled by sRNA sequencing.Differentially expressed microRNAs(miRNAs)were compared to mouse liver-enriched miRNAs and previously reported circulating miRNAs related to human liver diseases.The biological significance was evaluated by Ingenuity Pathway Analysis of altered sEV miRNAs and conditioned cultures of ALI serum sEVs with primary hepatic macrophages.RESULTS We found that both ALI and CLI changed the concentration and morphology of serum sEVs.The proportion of serum sEV miRNAs increased upon liver injury,with the liver as the primary contributor.The altered serum sEV miRNAs based on mouse studies were consistent with human liver disease-related circulating miRNAs.We established serum sEV miRNA signatures for ALI and CLI and a panel of miRNAs(miR-122-5p,miR-192-5p,and miR-22-3p)as a common marker for liver injury.The differential serum sEV miRNAs in ALI contributed mainly to liver steatosis and inflammation,while those in CLI contributed primarily to hepatocellular carcinoma and hyperplasia.ALI serum sEVs decreased both CD86 and CD206 expression in monocyte-derived macrophages but increased CD206 expression in resident macrophages in vitro.CONCLUSION Serum sEVs acquired different concentrations,sizes,morphologies and sRNA contents upon liver injury and could change the phenotype of liver macrophages.Serum sEVs therefore have good diagnostic and therapeutic potential for liver injury.展开更多
Rheumatoid arthritis(RA)is an autoimmune disease with a complex etiology.Monocyte-derived macrophages(MDMs)infiltration are associated with RA severity.We have reported the deletion of G-protein-coupled receptor kinas...Rheumatoid arthritis(RA)is an autoimmune disease with a complex etiology.Monocyte-derived macrophages(MDMs)infiltration are associated with RA severity.We have reported the deletion of G-protein-coupled receptor kinase 2(GRK2)reprograms macrophages toward an anti-inflammatory phenotype by recovering G-protein-coupled receptor signaling.However,as more GRK2-interacting proteins were discovered,the GRK2 interactome mechanisms in RA have been understudied.Thus,in the collagen-induced arthritis mouse model,we performed genetic GRK2 deletion using GRK2^(f/f)Lyz2-Cre^(+/−)mice.Synovial inflammation and M1 polarization were improved in GRK2^(f/f)Lyz2-Cre^(+/−)mice.Supporting experiments with RNA-seq and dual-luciferase reporter assays identified peroxisome proliferator-activated receptorγ(PPARγ)as a new GRK2-interacting protein.We further confirmed that fms-related tyrosine kinase 1(Flt-1),which promoted macrophage migration to induce angiogenesis,was inhibited by GRK2-PPARγsignaling.Mechanistically,excess GRK2 membrane recruitment in CIA MDMs reduced the activation of PPARγligand-binding domain and enhanced Flt-1 transcription.Furthermore,the treatment of mice with GRK2 activity inhibitor resulted in significantly diminished CIA pathology,Flt-1^(+)macrophages induced-synovial inflammation,and angiogenesis.Altogether,we anticipate to facilitate the elucidation of previously unappreciated details of GRK2-specific intracellular signaling.Targeting GRK2 activity is a viable strategy to inhibit MDMs infiltration,affording a distinct way to control joint inflammation and angiogenesis of RA.展开更多
In advanced hepatocellular carcinoma(HCC)tissues,M2-like tumor-associated macrophages(TAMs)are in the majority and promotes HCC progression.Contrary to the pro-tumor effect of M2-like TAMs,M1-like TAMs account for a s...In advanced hepatocellular carcinoma(HCC)tissues,M2-like tumor-associated macrophages(TAMs)are in the majority and promotes HCC progression.Contrary to the pro-tumor effect of M2-like TAMs,M1-like TAMs account for a small proportion and have anti-tumor effects.Since TAMs can switch from one type to another,reprogramming TAMs may be an important treatment for HCC therapy.However,the mechanisms of phenotypic switch and reprogramming TAMs are still obscure.In this study,we analyzed differential genes in normal macrophages and TAMs,and found that loss of MANF in TAMs accompanied by high levels of downstream genes negatively regulated by MANF.MANF reprogrammed TAMs into M1 phenotype.Meanwhile,loss of MANF promoted HCC progression in HCC patients and mice HCC model,especially tumor neovascularization.Additionally,macrophages with MANF supplement suppressed HCC progression in mice,suggesting MANF supplement in macrophage was an effective treatment for HCC.Mechanistically,MANF enhanced the HSF1-HSP70-1 interaction,restricted HSF1 in the cytoplasm of macrophages,and decreased both mRNA and protein levels of HSP70-1,which in turn led to reprogramming TAMs,and suppressing neovascularization of HCC.Our study contributes to the exploration the mechanism of TAMs reprogramming,which may provide insights for future therapeutic exploitation of HCC neovascularization.展开更多
Macrophages,which are key cellular components of the liver,have emerged as essential players in the maintenance of hepatic homeostasis and in injury and repair processes in acute and chronic liver diseases.Upon liver ...Macrophages,which are key cellular components of the liver,have emerged as essential players in the maintenance of hepatic homeostasis and in injury and repair processes in acute and chronic liver diseases.Upon liver injury,resident Kupffer cells(KCs)sense disturbances in homeostasis,interact with hepatic cell populations and release chemokines to recruit circulating leukocytes,including monocytes,which subsequently differentiate into monocyte-derived macrophages(MoMφs)in the liver.Both KCs and MoMφs contribute to both the progression and resolution of tissue inflammation and injury in various liver diseases.The diversity of hepatic macrophage subsets and their plasticity explain their different functional responses in distinct liver diseases.In this review,we highlight novel findings regarding the origins and functions of hepatic macrophages and discuss the potential of targeting macrophages as a therapeutic strategy for liver disease.展开更多
Early and strong interferon type I (IFN-I) responses are usually associated with mild COVID-19 disease, whereas persistent orunregulated proinflammatory cytokine responses are associated with severe disease outcomes. ...Early and strong interferon type I (IFN-I) responses are usually associated with mild COVID-19 disease, whereas persistent orunregulated proinflammatory cytokine responses are associated with severe disease outcomes. Previous work suggested thatmonocyte-derived macrophages (MDMs) are resistant and unresponsive to SARS-CoV-2 infection. Here, we demonstrate that uponphagocytosis of SARS-CoV-2-infected cells, MDMs are activated and secrete IL-6 and TNF. Importantly, activated MDMs in turnmediate strong activation of plasmacytoid dendritic cells (pDCs), leading to the secretion of high levels of IFN-α and TNF.Furthermore, pDC activation promoted IL-6 production by MDMs. This kind of pDC activation was dependent on direct integrinmediated cell‒cell contacts and involved stimulation of the TLR7 and STING signaling pathways. Overall, the present studydescribes a novel and potent pathway of pDC activation that is linked to the macrophage-mediated clearance of infected cells.These findings suggest that a high infection rate by SARS-CoV-2 may lead to exaggerated cytokine responses, which maycontribute to tissue damage and severe disease.展开更多
Monocytes are key effectors in autoimmunity-related diseases in the central nervous system(CNS)due to the critical roles of these cells in the production of proinflammatory cytokines,differentiation of T-helper(Th)cel...Monocytes are key effectors in autoimmunity-related diseases in the central nervous system(CNS)due to the critical roles of these cells in the production of proinflammatory cytokines,differentiation of T-helper(Th)cells,and antigen presentation.The JAK-STAT signaling is crucial for initiating monocytes induced immune responses by relaying cytokines signaling.However,the role of this pathway in modulating the communication between monocytes and Th cells in the pathogenesis of multiple sclerosis(MS)is unclear.Here,we show that the JAK1/2/3 and STAT1/3/5/6 subtypes involved in the demyelination mediated by the differentiation of pathological Th1 and Th17 and the CNS-infiltrating inflammatory monocytes in experimental autoimmune encephalomyelitis(EAE),a model for MS.JAK inhibition prevented the CNS-infiltrating CCR2-dependent Ly6^(Chi)monocytes and monocyte-derived dendritic cells in EAE mice.In parallel,the proportion of GM-CSF^(+)CD4^(+)T cells and GM-CSF secretion were decreased in pathological Th17 cells by JAK inhibition,which in turns converted CNS-invading monocytes into antigen-presenting cells to mediate tissue damage.Together,our data highlight the therapeutic potential of JAK inhibition in treating EAE by blocking the GM-CSF-driven inflammatory signature of monocytes.展开更多
Epigenetic regulation has been attracting increasing attention due to its role in cell differentiation and behaviors.However,the epigenetic mechanisms that regulate human dendritic cell(DC)differentiation and developm...Epigenetic regulation has been attracting increasing attention due to its role in cell differentiation and behaviors.However,the epigenetic mechanisms that regulate human dendritic cell(DC)differentiation and development remain poorly understood.Our previous studies show that extracellular heat shock protein 70-like protein(HSP70L1)is a potent adjuvant of Th1 responses via stimulating DCs when released from cells;however,the role of intracellular HSP70L1 in DC differentiation and maturation remains unknown.Herein,we demonstrate that intracellular HSP70L1 inhibits human DC maturation by suppressing MHC and costimulatory molecule expression,in contrast to the adjuvant activity of extracellular HSP70L1.The stability of intracellular HSP70L1 is dependent on DNAJC2,a known epigenetic regulator.Mechanistically,intracellular HSP70L1 inhibits the recruitment of Ash1l to and maintains the repressive H3K27me3 and H2AK119Ub1 modifications on the promoter regions of costimulatory,MHC and STAT3 genes.Thus,intracellular HSP70L1 is an inhibitor of human DC maturation.Our results provide new insights into the epigenetic regulation of cell development by intracellular HSP70L1.展开更多
Neonatal arterial ischemic stroke(NAIS)and neonatal hypoxic-ischemic encephalopathy(HIE)are common causes of neurological impairments in infants,for which treatment options are very limited.NAIS and HIE induce an inna...Neonatal arterial ischemic stroke(NAIS)and neonatal hypoxic-ischemic encephalopathy(HIE)are common causes of neurological impairments in infants,for which treatment options are very limited.NAIS and HIE induce an innate immune response that involves the recruitment of peripheral immune cells,including monocytes,into the brain.Monocytes and monocyte-derived cells have the potential to contribute to both harmful and beneficial pathophysiological processes,such as neuroinflammation and brain repair,but their roles in NAIS and HIE remain poorly understood.Furthermore,recent evidence indicates that monocyte-derived macrophages can persist in the brain for several months following NAIS and HIE in mice,with possible long-lasting consequences that are still unknown.This review provides a comprehensive overview of the mechanisms of monocyte infiltration and their potential functions in the ischemic brain,focusing on HIE and NAIS.Therapeutic strategies targeting monocytes and the possibility of using monocytes for cell-based therapies are also discussed.展开更多
基金supported by grants from NHMRC (APP1125796)The Col Bambrick Memorial MND Research Grant+2 种基金The NTI MND Research Grantthe FightMND Foundationsupported by an NHMRC Senior Research Fellowship APP1118452。
文摘Microglia, the main driver of neuroinflammation, play a central role in the initiation and exacerbation of various neurodegenerative diseases and are now considered a promising therapeutic target. Previous studies on in vitro human microglia and in vivo rodent models lacked scalability, consistency, or physiological relevance, which deterred successful therapeutic outcomes for the past decade. Here we review human blood monocyte-derived microglia-like cells as a robust and consistent approach to generate a patient-specific microglia-like model that can be used in extensive cohort studies for drug testing. We will highlight the strength and applicability of human blood monocyte-derived microglia-like cells to increase translational outcomes by reviewing the advantages of human blood monocyte-derived microglia-like cells in addressing patient heterogeneity and stratification, the basis of personalized medicine.
基金supported by the National Key Technologies R&D Program of China(No.2021YFC2500700)the National Natural Science Foundation of China(No.82003406)+2 种基金the Natural Science Foundation of Hebei Province(H2022209073)the China Postdoctoral Science Foundation(2023M733985)the CAMS Institute of Respiratory Medicine Grant for Young Scholars(2023-ZF-69).
文摘Monocyte-derived macrophages(MoMacs)are the most important effector cells that cause pulmonary fibrosis.However,the characteristics of MoMac differentiation in silicosis and the mechanisms by which MoMacs affect the progression of pulmonary fibrosis remain unclear.Integration of single-cell and spatial transcriptomic analyses revealed that the silicosis niche was occupied by a subset of MoMacs,identified as Spp1hiMacs,which remain in an immature transitional state of differentiation during silicosis.This study investigated the mechanistic foundations of mitochondrial damage induced by the lipoprotein-associated phospholipase A2(Lp-PLA2,encoded by Pla2g7)–acyl-CoA:lysocardiolipin acyltransferase-1(ALCAT1)–cardiolipin(CL)signaling pathway,which interferes with Spp1hiMac differentiation.We demonstrated that in SiO_(2)-induced MoMacs,Lp-PLA2 induces abnormal CL acylation through the activation of ALCAT1,resulting in impaired mitochondrial localization of PINK1 and LC3B and mitochondrial autophagy defects.Simultaneously,lysosomal dysfunction causes the release of the lysosomal protein cathepsin B into the cytoplasm,which involves M1 and M2 macrophage polarization and the activation of proinflammatory and profibrotic pathways.Furthermore,we assessed the efficacy of the Lp-PLA2 inhibitor darapladib in ameliorating silica-induced pulmonary fibrosis in a murine model.Our findings enhance our understanding of silicosis pathogenesis and offer promising opportunities for developing targeted therapies to mitigate fibrotic progression and maintain lung function in affected individuals.
文摘In this experiment Toll-like receptor expression pattern in monocytes and monocyte-derived macrophages by lipopolysaccharide （LPS） stimulation was examined. Jugular venous blood was collected from four Japanese calves, and the peripheral blood mononuclear cells （PBMCs） were isolated. The cells were directly used for collecting monocytes by magnetic cell sorting or cultured for 7 days to collect monocyte-derived macrophages in Repcell. Then we analyzed the mRNA expression pattern of TLRs and cytokines in monocytes and monocyte-derived macrophages after LPS stimulation for 24 h. LPS stimulation of both monocytes and monocyte-derived macrophages resulted in an increase in the levels of mRNA transcripts for TNF-α IL-6 and IL-8. Moreover, TNF-α and IL-6 mRNA expressions were significantly augmented by LPS stimulation in monocyte-derived macrophages. TLRs mRNA expressions were unchanged after LPS stimulation of monocytes, while TLRs mRNA expressions in monocyte-derived macrophages were complicated. TLR1, 3, 5, 8 and 10 were significantly decreased after LPS stimulation and there were no differences in the mRNA expressions of TLR2, 4, 6 and 7 between the groups of control and LPS stimulation. Besides, no expression of TLR9 was found. As antigen presenting cells, monocytes and monocyte-derived macrophages respond differently to LPS, so they may have different functions in the innate immune system.
文摘Accumulating evidence suggests that the Thl immune .response induced by various antigens such as oxidized low density lipoprotein （ox-LDL） and heat shock proteins （HSPs） play a key role in the process of atherosclerosis.1Dendritic cells （DCs） are the most potent antigen-presenting cells （APCs） in the body with the unique ability to initiate a primary immune response to certain antigens by the activation of ＂naive＂ T cells.2 The maturation of DC with the upregulation of costimulatory molecules such as CD83, CD40, CD86, and major histocompatibility complex （MHC） class molecules such as human leukocyte antigen （HLA）-DR, is required for DC to activate T cells. Pathologic studies have shown that immature DCs are present in normal arterial while abundant mature DCs clustered with T cells could be visualized in atherogenic vessels suggesting that DC 3 maturation is linked to the progression of atherosclerosls. Peroxisome proliferator-activated receptors （PPARs） a, one member of the family of PPARs, was found to have favorable effects on slowing the progression of atherosclerosis and reducing the risk of coronary heart disease in high-risk patients independent from their metabolism effects.4＇5 Furthermore, PPAR-α is also expressed on monocytes and monocyte-derived DCs.6 The effects of PPAR-α on DCs maturation and immune function remain unknown now, we therefore observed the effects of fenofibrate, a PPAR-α agonist, on the maturation and immune function of oxidized LDL-treated DCs in this study.
文摘Dendritic cells （DCs） play a pivotal role in linking the innate immunity and acquired immunity in responses to pathogen. Non-human primates such as Chinese Rhesus Macaque （CRM） are the favorable models for preclinical study of potential therapeutic drugs, vaccines and mechanisms of human diseases. However, the phenotypical characterization of monocyte-derived dendritic cells （MDDCs） from CRM has not been elucidated. Monocytes from CRM were cultured with GM-CSF and IL-4 in RPMI-1640. Six days later, these cells were differentiated with typical dendritical morphology. CDllc and DC-SIGN were highly expressed. The immature MDDCs expressed the low levels of CD25, CD80, CD83, moderate CD40, CD86, and high MHC. After stimulation, the mature MDDCs increased expression of mature molecules CD25 and CD83, co-stimulatory molecules such as CD80, CD86 and CD40, and kept a high level of MHC. The capacity of endocytosis decreased with maturation. The mature MDDCs have strong ability of inducing allogeneic T cell proliferation and producing IL-12. In conclusion, we have characterized the phenotype and ultimate function of MDDCs from CRM for the first time.
基金supported by the National Natural Science Foundation of China(82172242)the Natural Science Foundation of Guangdong(2022A1515012053)the projects from Guangzhou Municipal Science and Technology Bureau(2023A04J1075).
文摘Naf1(Nef-associated factor 1)is a host protein that interacts with human immunodeficiency virus type 1(HIV-1)Nef protein.We and others have previously demonstrated that Naf1 restricts HIV-1 infection of T-lymphocytes.Myeloid cells are targets for HIV infection,but Naf1 expression in myeloid cells and whether it also regulates HIV infection in these cells are not yet identified.In this study,we found that Naf1 had a higher expression in CD14þmonocytes than in monocyte-derived dendritic cells(MDDCs),and its expression in both types of cells could be induced by HIV-1 gp120 glycoproteins or viral particles.Importantly,the expression of Naf1 restricted HIV-1 infection in monocytes and MDDCs.Functional investigation showed that both the constitutive and the induced expression of Naf1 inhibited NF-κB signaling in MDDCs and reduced the basal level or LPS(Lipopolysaccharide)-stimulated production of cytokines.Moreover,Naf1 reduced the expression of ICAM-1(intercellular cell adhesion molecule-1)on MDDCs and compromised their capacity to prime the activation of resting CD4^(+)T cells in co-culture.In light of the essential role of NF-κB signaling for HIV-1 transcription,Naf1-mediated inhibition of NF-κB signaling may hinder a robust viral replication in MDDCs and help maintain viral persistence.Furthermore,virus-induced Naf1 expression in MDDCs may diminish the cross-talk between DC(dendritic cell)and T cells,hence suppressing the activation of antiviral immune responses.Taken together,we identified the new function of Naf1 in myeloid cells.Those findings may facilitate the understanding for the host restriction of HIV-1 infection in myeloid cells.
基金supported by the National Natural Science Foundation of China(82071467)the International(Regional)Cooperation and Exchange Program of the National Natural Science Foundation of China(82111330075)+3 种基金the National Natural Science Foundation for Youth Scholars of China(81801053)the Innovation Team Support Plan of Universities in Liaoning Province(LT2019015)the Liaoning Provincial Key Research and Development Guidance Program(2019JH8/10300002)the Liaoning Revitalization Talents Plan(XLYC1802097).
文摘Interactions between brain-resident and periph-eral infiltrated immune cells are thought to contribute to neuroplasticity after cerebral ischemia.However,con-ventional bulk sequencing makes it challenging to depict this complex immune network.Using single-cell RNA sequencing,we mapped compositional and transcriptional features of peri-infarct immune cells.Microglia were the predominant cell type in the peri-infarct region,displaying a more diverse activation pattern than the typical pro-and anti-inflammatory state,with axon tract-associated micro-glia(ATMs)being associated with neuronal regeneration.Trajectory inference suggested that infiltrated monocyte-derived macrophages(MDMs)exhibited a gradual fate trajectory transition to activated MDMs.Inter-cellular crosstalk between MDMs and microglia orchestrated anti-inflammatory and repair-promoting microglia phenotypes and promoted post-stroke neurogenesis,with SOX2 and related Akt/CREB signaling as the underlying mechanisms.This description of the brain's immune landscape and its relationship with neurogenesis provides new insight into promoting neural repair by regulating neuroinflammatory responses.
文摘BACKGROUND Serum small extracellular vesicles(sEVs)and their small RNA(sRNA)cargoes could be promising biomarkers for the diagnosis of liver injury.However,the dynamic changes in serum sEVs and their sRNA components during liver injury have not been well characterized.Given that hepatic macrophages can quickly clear intravenously injected sEVs,the effect of liver injury-related serum sEVs on hepatic macrophages deserves to be explored.AIM To identify the characteristics of serum sEVs and the sRNAs during liver injury and explore their effects on hepatic macrophages.METHODS To identify serum sEV biomarkers for liver injury,we established a CCL4-induced mouse liver injury model in C57BL/6 mice to simulate acute liver injury(ALI),chronic liver injury(CLI)and recovery.Serum sEVs were obtained and characterized by transmission electron microscopy and nanoparticle tracking analysis.Serum sEV sRNAs were profiled by sRNA sequencing.Differentially expressed microRNAs(miRNAs)were compared to mouse liver-enriched miRNAs and previously reported circulating miRNAs related to human liver diseases.The biological significance was evaluated by Ingenuity Pathway Analysis of altered sEV miRNAs and conditioned cultures of ALI serum sEVs with primary hepatic macrophages.RESULTS We found that both ALI and CLI changed the concentration and morphology of serum sEVs.The proportion of serum sEV miRNAs increased upon liver injury,with the liver as the primary contributor.The altered serum sEV miRNAs based on mouse studies were consistent with human liver disease-related circulating miRNAs.We established serum sEV miRNA signatures for ALI and CLI and a panel of miRNAs(miR-122-5p,miR-192-5p,and miR-22-3p)as a common marker for liver injury.The differential serum sEV miRNAs in ALI contributed mainly to liver steatosis and inflammation,while those in CLI contributed primarily to hepatocellular carcinoma and hyperplasia.ALI serum sEVs decreased both CD86 and CD206 expression in monocyte-derived macrophages but increased CD206 expression in resident macrophages in vitro.CONCLUSION Serum sEVs acquired different concentrations,sizes,morphologies and sRNA contents upon liver injury and could change the phenotype of liver macrophages.Serum sEVs therefore have good diagnostic and therapeutic potential for liver injury.
基金We thank LetPub(www.letpub.com)for its linguistic assistance during the preparation of this manuscript.We thank all the patients who participated in providing us with synovial tissues and blood samples.Graphical abstract was created with BioRender.com(publication and licensing rights number JZ25ROGTF8)This study was supported by the National Natural Science Foundation of China(No.82003763,No.81973332,No.82173824,No.82204405,No.82204402)+2 种基金Research Fund of Anhui Institute of translational medicine(2022zhyx-B04,China)The 2022 Basic and Clinical Collaborative Research of Anhui Medical University(2022sfy015,China)Natural Science Foundation of Anhui Provincial(2108085QH383,China).
文摘Rheumatoid arthritis(RA)is an autoimmune disease with a complex etiology.Monocyte-derived macrophages(MDMs)infiltration are associated with RA severity.We have reported the deletion of G-protein-coupled receptor kinase 2(GRK2)reprograms macrophages toward an anti-inflammatory phenotype by recovering G-protein-coupled receptor signaling.However,as more GRK2-interacting proteins were discovered,the GRK2 interactome mechanisms in RA have been understudied.Thus,in the collagen-induced arthritis mouse model,we performed genetic GRK2 deletion using GRK2^(f/f)Lyz2-Cre^(+/−)mice.Synovial inflammation and M1 polarization were improved in GRK2^(f/f)Lyz2-Cre^(+/−)mice.Supporting experiments with RNA-seq and dual-luciferase reporter assays identified peroxisome proliferator-activated receptorγ(PPARγ)as a new GRK2-interacting protein.We further confirmed that fms-related tyrosine kinase 1(Flt-1),which promoted macrophage migration to induce angiogenesis,was inhibited by GRK2-PPARγsignaling.Mechanistically,excess GRK2 membrane recruitment in CIA MDMs reduced the activation of PPARγligand-binding domain and enhanced Flt-1 transcription.Furthermore,the treatment of mice with GRK2 activity inhibitor resulted in significantly diminished CIA pathology,Flt-1^(+)macrophages induced-synovial inflammation,and angiogenesis.Altogether,we anticipate to facilitate the elucidation of previously unappreciated details of GRK2-specific intracellular signaling.Targeting GRK2 activity is a viable strategy to inhibit MDMs infiltration,affording a distinct way to control joint inflammation and angiogenesis of RA.
基金funded by support programs for Jun Liu,including the National Natural Science Foundation of China(82073862)Excellent Youth Talent Program of Anhui Province Natural Science Foundation(2108085Y27,China)funded by Anhui Province Natural Science Foundation(2208085MH284,China)for Xiangpeng Hu,and funded by the National Natural Science Foundation of China(U21A20345)for Yuxian Shen。
文摘In advanced hepatocellular carcinoma(HCC)tissues,M2-like tumor-associated macrophages(TAMs)are in the majority and promotes HCC progression.Contrary to the pro-tumor effect of M2-like TAMs,M1-like TAMs account for a small proportion and have anti-tumor effects.Since TAMs can switch from one type to another,reprogramming TAMs may be an important treatment for HCC therapy.However,the mechanisms of phenotypic switch and reprogramming TAMs are still obscure.In this study,we analyzed differential genes in normal macrophages and TAMs,and found that loss of MANF in TAMs accompanied by high levels of downstream genes negatively regulated by MANF.MANF reprogrammed TAMs into M1 phenotype.Meanwhile,loss of MANF promoted HCC progression in HCC patients and mice HCC model,especially tumor neovascularization.Additionally,macrophages with MANF supplement suppressed HCC progression in mice,suggesting MANF supplement in macrophage was an effective treatment for HCC.Mechanistically,MANF enhanced the HSF1-HSP70-1 interaction,restricted HSF1 in the cytoplasm of macrophages,and decreased both mRNA and protein levels of HSP70-1,which in turn led to reprogramming TAMs,and suppressing neovascularization of HCC.Our study contributes to the exploration the mechanism of TAMs reprogramming,which may provide insights for future therapeutic exploitation of HCC neovascularization.
基金supported by the Federal Ministry of Education and Research(BMBF,ImmuneAvatar)supported by NIH grants DK109574,DK121330,DK122708,and DK122796supported by the German Research Foundation(DFG SFB/TRR296,CRC1382,Ta434/3-1,and Ta434/5-1).
文摘Macrophages,which are key cellular components of the liver,have emerged as essential players in the maintenance of hepatic homeostasis and in injury and repair processes in acute and chronic liver diseases.Upon liver injury,resident Kupffer cells(KCs)sense disturbances in homeostasis,interact with hepatic cell populations and release chemokines to recruit circulating leukocytes,including monocytes,which subsequently differentiate into monocyte-derived macrophages(MoMφs)in the liver.Both KCs and MoMφs contribute to both the progression and resolution of tissue inflammation and injury in various liver diseases.The diversity of hepatic macrophage subsets and their plasticity explain their different functional responses in distinct liver diseases.In this review,we highlight novel findings regarding the origins and functions of hepatic macrophages and discuss the potential of targeting macrophages as a therapeutic strategy for liver disease.
文摘Early and strong interferon type I (IFN-I) responses are usually associated with mild COVID-19 disease, whereas persistent orunregulated proinflammatory cytokine responses are associated with severe disease outcomes. Previous work suggested thatmonocyte-derived macrophages (MDMs) are resistant and unresponsive to SARS-CoV-2 infection. Here, we demonstrate that uponphagocytosis of SARS-CoV-2-infected cells, MDMs are activated and secrete IL-6 and TNF. Importantly, activated MDMs in turnmediate strong activation of plasmacytoid dendritic cells (pDCs), leading to the secretion of high levels of IFN-α and TNF.Furthermore, pDC activation promoted IL-6 production by MDMs. This kind of pDC activation was dependent on direct integrinmediated cell‒cell contacts and involved stimulation of the TLR7 and STING signaling pathways. Overall, the present studydescribes a novel and potent pathway of pDC activation that is linked to the macrophage-mediated clearance of infected cells.These findings suggest that a high infection rate by SARS-CoV-2 may lead to exaggerated cytokine responses, which maycontribute to tissue damage and severe disease.
基金supported by the National Natural Science Foundation of China(82293684,82293680,82104189,82273929)the National Key R&D Program of China(2020YFA0908004)+1 种基金CAMS Innovation Fund for Medical Science(2021-I2M-1-028,2022-I2M-2-002,2022-I2M-1-014,China)Special Research Fund for Central Universities,Peking Union Medical College grant(3332022146,China)。
文摘Monocytes are key effectors in autoimmunity-related diseases in the central nervous system(CNS)due to the critical roles of these cells in the production of proinflammatory cytokines,differentiation of T-helper(Th)cells,and antigen presentation.The JAK-STAT signaling is crucial for initiating monocytes induced immune responses by relaying cytokines signaling.However,the role of this pathway in modulating the communication between monocytes and Th cells in the pathogenesis of multiple sclerosis(MS)is unclear.Here,we show that the JAK1/2/3 and STAT1/3/5/6 subtypes involved in the demyelination mediated by the differentiation of pathological Th1 and Th17 and the CNS-infiltrating inflammatory monocytes in experimental autoimmune encephalomyelitis(EAE),a model for MS.JAK inhibition prevented the CNS-infiltrating CCR2-dependent Ly6^(Chi)monocytes and monocyte-derived dendritic cells in EAE mice.In parallel,the proportion of GM-CSF^(+)CD4^(+)T cells and GM-CSF secretion were decreased in pathological Th17 cells by JAK inhibition,which in turns converted CNS-invading monocytes into antigen-presenting cells to mediate tissue damage.Together,our data highlight the therapeutic potential of JAK inhibition in treating EAE by blocking the GM-CSF-driven inflammatory signature of monocytes.
基金We thank Yanfeng Li for the technical assistance.This work was supported by grants from the National Key R&D Program of China(2018YFA0507401)the National Natural Science Foundation of China(31670875 and 31470858).
文摘Epigenetic regulation has been attracting increasing attention due to its role in cell differentiation and behaviors.However,the epigenetic mechanisms that regulate human dendritic cell(DC)differentiation and development remain poorly understood.Our previous studies show that extracellular heat shock protein 70-like protein(HSP70L1)is a potent adjuvant of Th1 responses via stimulating DCs when released from cells;however,the role of intracellular HSP70L1 in DC differentiation and maturation remains unknown.Herein,we demonstrate that intracellular HSP70L1 inhibits human DC maturation by suppressing MHC and costimulatory molecule expression,in contrast to the adjuvant activity of extracellular HSP70L1.The stability of intracellular HSP70L1 is dependent on DNAJC2,a known epigenetic regulator.Mechanistically,intracellular HSP70L1 inhibits the recruitment of Ash1l to and maintains the repressive H3K27me3 and H2AK119Ub1 modifications on the promoter regions of costimulatory,MHC and STAT3 genes.Thus,intracellular HSP70L1 is an inhibitor of human DC maturation.Our results provide new insights into the epigenetic regulation of cell development by intracellular HSP70L1.
基金Conselho Nacional de Desenvolvimento Científico e Tecnológico(CNPq),Grant/Award Number:13757/2020-8Fundação de AmparoàPesquisa do Estado do Rio de Janeiro(FAPERJ),Grant/Award Numbers:E-26/201.279/2021,E-26/203.227/2017。
文摘Neonatal arterial ischemic stroke(NAIS)and neonatal hypoxic-ischemic encephalopathy(HIE)are common causes of neurological impairments in infants,for which treatment options are very limited.NAIS and HIE induce an innate immune response that involves the recruitment of peripheral immune cells,including monocytes,into the brain.Monocytes and monocyte-derived cells have the potential to contribute to both harmful and beneficial pathophysiological processes,such as neuroinflammation and brain repair,but their roles in NAIS and HIE remain poorly understood.Furthermore,recent evidence indicates that monocyte-derived macrophages can persist in the brain for several months following NAIS and HIE in mice,with possible long-lasting consequences that are still unknown.This review provides a comprehensive overview of the mechanisms of monocyte infiltration and their potential functions in the ischemic brain,focusing on HIE and NAIS.Therapeutic strategies targeting monocytes and the possibility of using monocytes for cell-based therapies are also discussed.
