Objective:To observe the effect of Pingchuan granule on the number of typeⅡinnate lymphocytes(ILC2)and M2 polarization of macrophages in the lung tissue of asthmatic mice;Methods:Ovalbumin sensitized and challenged a...Objective:To observe the effect of Pingchuan granule on the number of typeⅡinnate lymphocytes(ILC2)and M2 polarization of macrophages in the lung tissue of asthmatic mice;Methods:Ovalbumin sensitized and challenged asthmatic mouse models were established,and then Pingchuan granules or IL-33 neutralizing antibody were given to intervene.The pathological morphology of lung tissue was observed by HE,PAS and Masson staining,and the expressions of IL-4,IL-5,IL-13 and IL-33 in BALF and lung tissue were detected by ELISA and qRT-PCR,Flow cytometry was used to detect the number of type II innate lymphocytes and type M2 macrophages in lung tissue.Western blot was used to detect the protein expression levels of ST-2,FIZZ1 and Arg-1 in lung tissue;Results:Compared with the control group,the inflammation score,PAS score and collagen staining area of the model group were significantly increased,the expressions of IL-4,IL-5,IL-13 and IL-33 in BALF and lung tissue were significantly increased,the number of ILC2 and M2 macrophages,the expression of ST-2,FIZZ1 and Arg-1 protein in lung tissue were significantly increased,and the differences were statistically significant(P<0.05);Compared with the model group,Pingchuan granule could significantly reduce the inflammation score,PAS score and collagen staining area of asthmatic mice,down-regulate the expression of IL-4,IL-5,IL-13 and IL-33 in BALF and lung tissue,reduce the number of ILC2 and M2 macrophages,and the expression of ST-2,FIZZ1 and Arg-1 protein in lung tissue(P<0.05);Conclusion:Pingchuan granule improve the airway remodeling of asthma by inhibiting the polarization of M2 macrophages mediated by ILC2.展开更多
BACKGROUND Gastric cancer is a prevalent malignant cancer with a high incidence and significantly affects the health of modern people globally.Cisplatin(DDP)is one of the most common and effective chemotherapies for p...BACKGROUND Gastric cancer is a prevalent malignant cancer with a high incidence and significantly affects the health of modern people globally.Cisplatin(DDP)is one of the most common and effective chemotherapies for patients with gastric cancer,but DDP resistance remains a severe clinical challenge.AIM To explore the function of M2 polarized macrophages-derived exosomal microRNA(miR)-588 in the modulation of DDP resistance of gastric cancer cells.METHODS M2 polarized macrophages were isolated and identified by specific markers using flow cytometry analysis.The exosomes from M2 macrophages were identified by transmission electron microscopy and related markers.The uptake of the PKH67-labelled M2 macrophages-derived exosomes was detected in SGC7901 cells.The function and mechanism of exosomal miR-588 from M2 macrophages in the modulation of DDP resistance of gastric cancer cells was analyzed by CCK-8 assay,apoptosis analysis,colony formation assay,Western blot analysis,qPCR analysis,and luciferase reporter assay in SGC7901 and SGC7901/DDP cells,and by tumorigenicity analysis in nude mice.RESULTS M2 polarized macrophages were isolated from mouse bone marrow stimulated with interleukin(IL)-13 and IL-4.Co-cultivation of gastric cancer cells with M2 polarized macrophages promoted DDP resistance.M2 polarized macrophagesderived exosomes could transfer in gastric cancer cells to enhance DDP resistance.Exosomal miR-588 from M2 macrophages contributed to DDP resistance of gastric cancer cells.miR-588 promoted DDP-resistant gastric cancer cell growth in vivo.miR-588 was able to target cylindromatosis(CYLD)in gastric cancer cells.The depletion of CYLD reversed miR-588 inhibition-regulated cell proliferation and apoptosis of gastric cancer cells exposed to DDP.CONCLUSION In conclusion,we uncovered that exosomal miR-588 from M2 macrophages contributes to DDP resistance of gastric cancer cells by partly targeting CYLD.miR-588 may be applied as a potential therapeutic target for the treatment of gastric cancer.展开更多
Pathologic inflammatory conditions are frequently correlated with dynamic alterations through macrophage activation,with classically activated Ml cells associated with promoting and sustaining inflammation and M2 cell...Pathologic inflammatory conditions are frequently correlated with dynamic alterations through macrophage activation,with classically activated Ml cells associated with promoting and sustaining inflammation and M2 cells implicated in resolving or smoldering chronic inflammation.Inflammation is a common feature of various chronic diseases,and it has direct involvement in the emergence and progression of these conditions.Macrophages participate in an autoregulatory loop characterizing inflammatory process,as they produce a wide range of biologically active mediators that exert either deleterious or beneficial effects during inflammation.Therefore,balancing the ratio of M1/M2 macrophages can help to ameliorate the inflammatory landscape of pathological conditions.This review will explore the role of macrophage polarization in distant pathological inflammatory conditions,such as cancer,autoimmunity,renal inflammation,stroke,and atherosclerosis,while sharing macrophage-driven pathogenesis.展开更多
Axons in central nervous system(CNS) do not regenerate spontaneously after injuries such as stroke and traumatic spinal cord injury.Both intrinsic and extrinsic factors are responsible for the regeneration failure.Alt...Axons in central nervous system(CNS) do not regenerate spontaneously after injuries such as stroke and traumatic spinal cord injury.Both intrinsic and extrinsic factors are responsible for the regeneration failure.Although intensive research efforts have been invested on extrinsic regeneration inhibitors,the extent to which glial inhibitors contribute to the regeneration failure in vivo still remains elusive.Recent experimental evidence has rekindled interests in intrinsic factors for the regulation of regeneration capacity in adult mammals.In this review,we propose that activating macrophages with pro-regenerative molecular signatures could be a novel approach for boosting intrinsic regenerative capacity of CNS neurons.Using a conditioning injury model in which regeneration of central branches of dorsal root ganglia sensory neurons is enhanced by a preceding injury to the peripheral branches,we have demonstrated that perineuronal macrophages surrounding dorsal root ganglia neurons are critically involved in the maintenance of enhanced regeneration capacity.Neuron-derived chemokine(C-C motif) ligand 2(CCL2) seems to mediate neuron-macrophage interactions conveying injury signals to perineuronal macrophages taking on a soley pro-regenerative phenotype,which we designate as regeneration-associated macrophages(RAMs).Manipulation of the CCL2 signaling could boost regeneration potential mimicking the conditioning injury,suggesting that the chemokine-mediated RAM activation could be utilized as a regenerative therapeutic strategy for CNS injuries.展开更多
Tumor-associated macrophages(TAMs),one of the dominating constituents of tumor microenvironment,are important contributors to cancer progression and treatment resistance.Therefore,regulation of TAMs polarization from ...Tumor-associated macrophages(TAMs),one of the dominating constituents of tumor microenvironment,are important contributors to cancer progression and treatment resistance.Therefore,regulation of TAMs polarization from M2 phenotype towards M1 phenotype has emerged as a new strategy for tumor immunotherapy.Herein,we successfully initiated antitumor immunotherapy by inhibiting TAMs M2 polarization via autophagy intervention with polyethylene glycol-conjugated gold nanoparticles(PEG-Au NPs).PEG-Au NPs suppressed TAMs M2 polarization in both in vitro and in vivo models,elicited antitumor immunotherapy and inhibited subcutaneous tumor growth in mice.As demonstrated by the m RFP-GFP-LC3 assay and analyzing the autophagy-related proteins(LC3,beclin1 and P62),PEGAu NPs induced autophagic flux inhibition in TAMs,which is attributed to the PEG-Au NPs induced lysosome alkalization and membrane permeabilization.Besides,TAMs were prone to polarize towards M2phenotype following autophagy activation,whereas inhibition of autophagic flux could reduce the M2polarization of TAMs.Our results revealed a mechanism underlying PEG-Au NPs induced antitumor immunotherapy,where PEG-Au NPs reduce TAMs M2 polarization via induction of lysosome dysfunction and autophagic flux inhibition.This study elucidated the biological effects of nanomaterials on TAMs polarization and provided insight into harnessing the intrinsic immunomodulation capacity of nanomaterials for effective cancer treatment.展开更多
Background:Understanding how the tumor microenvironment is shaped by various factors is important for the development of new therapeutic strategies.Tumor cells often undergo spontaneous apoptotic cell death in tumor m...Background:Understanding how the tumor microenvironment is shaped by various factors is important for the development of new therapeutic strategies.Tumor cells often undergo spontaneous apoptotic cell death in tumor microen-vironment,these apoptotic cells are histologically co-localized with immunosup-pressive macrophages.However,the mechanism by which tumor cell apoptosis modulates macrophage polarization is not fully understood.In this study,we aimed to explore the tumor promoting effects of apoptotic tumor cells and the signal pathways involved.Methods:Apoptotic cells and macrophages in tumors were detected by immunohistochemical staining.Morphological analysis was performed with Giemsa staining.Lipids generated from apoptotic cells were detected by liq-uid chromatography-mass spectrometry.Phosphatidylserine-containing lipo-somes were prepared to mimic apoptotic cells.The expression of protein was determined by real-time PCR,immunohistochemistry enzyme-linked immunosorbent assay and Western blotting.Mouse malignant ascites and subcu-taneous tumor models were designed for in vivo analysis.Transgenic mice with specific genes knocked out and inhibitors specific to certain proteins were used for the mechanistic studies.Results:The location and the number of apoptotic cells were correlated with that of macrophages in several types of carcinomas.Phosphatidylserine,a lipid molecule generated in apoptotic cells,induced polarization and accumulation of M2-like macrophages in vivo and in vitro.Moreover,sustained administration of phosphoserine promoted tumor growth in the malignant ascites and subcuta-neous tumor models.Further analyses suggested that phosphoserine induced a M2-like phenotype in macrophages,which was related to the activation of phosphoserine receptors including T-cell immunoglobin mucin 4(TIM4)and the FAK-SRC-STAT3 signaling pathway as well as elevated the expression of the histone demethylase Jumonji domain-containing protein 3(JMJD3).Adminis-tration of specific inhibitors of these pathways could reduce tumor progression.Conclusions:This study suggest that apoptotic cell-generated phosphoserine might be a notable signal for immunosuppressive macrophages in tumors,and the related pathways might be potential therapeutic targets for cancer therapy.展开更多
Diabetes mellitus is a chronically inflamed disease that predisposes to delayed fracture healing.Macrophages play a key role in the process of fracture healing by undergoing polarization into either M1 or M2 subtypes,...Diabetes mellitus is a chronically inflamed disease that predisposes to delayed fracture healing.Macrophages play a key role in the process of fracture healing by undergoing polarization into either M1 or M2 subtypes,which respectively exhibit pro-inflammatory or anti-inflammatory functions.Therefore,modulation of macrophage polarization to the M2 subtype is beneficial for fracture healing.Exosomes perform an important role in improving the osteoimmune microenvironment due to their extremely low immunogenicity and high bioactivity.In this study,we extracted the M2-exosomes and used them to intervene the bone repair in diabetic fractures.The results showed that M2-exosomes significantly modulate the osteoimmune microenvironment by decreasing the proportion of M1 macrophages,thereby accelerating diabetic fracture healing.We further confirmed that M2-exosomes induced the conversion of M1 macrophages into M2 macrophages by stimulating the PI3K/AKT pathway.Our study offers a fresh perspective and a potential therapeutic approach for M2-exosomes to improve diabetic fracture healing.展开更多
Osteoarthritis(OA),in which M1 macrophage polarization in the synovium exacerbates disease progression,is a major cause of cartilage degeneration and functional disabilities.Therapeutic strategies of OA designed to in...Osteoarthritis(OA),in which M1 macrophage polarization in the synovium exacerbates disease progression,is a major cause of cartilage degeneration and functional disabilities.Therapeutic strategies of OA designed to interfere with the polarization of macrophages have rarely been reported.Here,we report that SHP099,as an allosteric inhibitor of src-homology 2-containing protein tyrosine phosphatase 2(SHP2),attenuated osteoarthritis progression by inhibiting M1 macrophage polarization.We demonstrated that M1 macrophage polarization was accompanied by the overexpression of SHP2 in the synovial tissues of OA patients and OA model mice.Compared to wild-type(WT)mice,myeloid lineage conditional Shp2 knockout(c KO)mice showed decreased M1 macrophage polarization and attenuated severity of synovitis,an elevated expression of cartilage phenotype protein collagen II(COL2),and a decreased expression of cartilage degradation markers collagen X(COL10)and matrix metalloproteinase3(MMP3)in OA cartilage.Further mechanistic analysis showed that SHP099 inhibited lipopolysaccharide(LPS)-induced Toll-like receptor(TLR)signaling mediated by nuclear factor kappa B(NF-κB)and PI3K—AKT signaling.Moreover,intra-articular injection of SHP099 also significantly attenuated OA progression,including joint synovitis and cartilage damage.These results indicated that allosteric inhibition of SHP2 might be a promising therapeutic strategy for the treatment of OA.展开更多
基金General Program of the National Natural Science Foundation of China(No.82074365)General Program of the Natural Science Foundation of Heilongjiang Province(No.H2017068)Harbin City Applied Technology Research and Development Project(No.2017RAXXJ053)。
文摘Objective:To observe the effect of Pingchuan granule on the number of typeⅡinnate lymphocytes(ILC2)and M2 polarization of macrophages in the lung tissue of asthmatic mice;Methods:Ovalbumin sensitized and challenged asthmatic mouse models were established,and then Pingchuan granules or IL-33 neutralizing antibody were given to intervene.The pathological morphology of lung tissue was observed by HE,PAS and Masson staining,and the expressions of IL-4,IL-5,IL-13 and IL-33 in BALF and lung tissue were detected by ELISA and qRT-PCR,Flow cytometry was used to detect the number of type II innate lymphocytes and type M2 macrophages in lung tissue.Western blot was used to detect the protein expression levels of ST-2,FIZZ1 and Arg-1 in lung tissue;Results:Compared with the control group,the inflammation score,PAS score and collagen staining area of the model group were significantly increased,the expressions of IL-4,IL-5,IL-13 and IL-33 in BALF and lung tissue were significantly increased,the number of ILC2 and M2 macrophages,the expression of ST-2,FIZZ1 and Arg-1 protein in lung tissue were significantly increased,and the differences were statistically significant(P<0.05);Compared with the model group,Pingchuan granule could significantly reduce the inflammation score,PAS score and collagen staining area of asthmatic mice,down-regulate the expression of IL-4,IL-5,IL-13 and IL-33 in BALF and lung tissue,reduce the number of ILC2 and M2 macrophages,and the expression of ST-2,FIZZ1 and Arg-1 protein in lung tissue(P<0.05);Conclusion:Pingchuan granule improve the airway remodeling of asthma by inhibiting the polarization of M2 macrophages mediated by ILC2.
文摘BACKGROUND Gastric cancer is a prevalent malignant cancer with a high incidence and significantly affects the health of modern people globally.Cisplatin(DDP)is one of the most common and effective chemotherapies for patients with gastric cancer,but DDP resistance remains a severe clinical challenge.AIM To explore the function of M2 polarized macrophages-derived exosomal microRNA(miR)-588 in the modulation of DDP resistance of gastric cancer cells.METHODS M2 polarized macrophages were isolated and identified by specific markers using flow cytometry analysis.The exosomes from M2 macrophages were identified by transmission electron microscopy and related markers.The uptake of the PKH67-labelled M2 macrophages-derived exosomes was detected in SGC7901 cells.The function and mechanism of exosomal miR-588 from M2 macrophages in the modulation of DDP resistance of gastric cancer cells was analyzed by CCK-8 assay,apoptosis analysis,colony formation assay,Western blot analysis,qPCR analysis,and luciferase reporter assay in SGC7901 and SGC7901/DDP cells,and by tumorigenicity analysis in nude mice.RESULTS M2 polarized macrophages were isolated from mouse bone marrow stimulated with interleukin(IL)-13 and IL-4.Co-cultivation of gastric cancer cells with M2 polarized macrophages promoted DDP resistance.M2 polarized macrophagesderived exosomes could transfer in gastric cancer cells to enhance DDP resistance.Exosomal miR-588 from M2 macrophages contributed to DDP resistance of gastric cancer cells.miR-588 promoted DDP-resistant gastric cancer cell growth in vivo.miR-588 was able to target cylindromatosis(CYLD)in gastric cancer cells.The depletion of CYLD reversed miR-588 inhibition-regulated cell proliferation and apoptosis of gastric cancer cells exposed to DDP.CONCLUSION In conclusion,we uncovered that exosomal miR-588 from M2 macrophages contributes to DDP resistance of gastric cancer cells by partly targeting CYLD.miR-588 may be applied as a potential therapeutic target for the treatment of gastric cancer.
文摘Pathologic inflammatory conditions are frequently correlated with dynamic alterations through macrophage activation,with classically activated Ml cells associated with promoting and sustaining inflammation and M2 cells implicated in resolving or smoldering chronic inflammation.Inflammation is a common feature of various chronic diseases,and it has direct involvement in the emergence and progression of these conditions.Macrophages participate in an autoregulatory loop characterizing inflammatory process,as they produce a wide range of biologically active mediators that exert either deleterious or beneficial effects during inflammation.Therefore,balancing the ratio of M1/M2 macrophages can help to ameliorate the inflammatory landscape of pathological conditions.This review will explore the role of macrophage polarization in distant pathological inflammatory conditions,such as cancer,autoimmunity,renal inflammation,stroke,and atherosclerosis,while sharing macrophage-driven pathogenesis.
文摘Axons in central nervous system(CNS) do not regenerate spontaneously after injuries such as stroke and traumatic spinal cord injury.Both intrinsic and extrinsic factors are responsible for the regeneration failure.Although intensive research efforts have been invested on extrinsic regeneration inhibitors,the extent to which glial inhibitors contribute to the regeneration failure in vivo still remains elusive.Recent experimental evidence has rekindled interests in intrinsic factors for the regulation of regeneration capacity in adult mammals.In this review,we propose that activating macrophages with pro-regenerative molecular signatures could be a novel approach for boosting intrinsic regenerative capacity of CNS neurons.Using a conditioning injury model in which regeneration of central branches of dorsal root ganglia sensory neurons is enhanced by a preceding injury to the peripheral branches,we have demonstrated that perineuronal macrophages surrounding dorsal root ganglia neurons are critically involved in the maintenance of enhanced regeneration capacity.Neuron-derived chemokine(C-C motif) ligand 2(CCL2) seems to mediate neuron-macrophage interactions conveying injury signals to perineuronal macrophages taking on a soley pro-regenerative phenotype,which we designate as regeneration-associated macrophages(RAMs).Manipulation of the CCL2 signaling could boost regeneration potential mimicking the conditioning injury,suggesting that the chemokine-mediated RAM activation could be utilized as a regenerative therapeutic strategy for CNS injuries.
基金supported by the National Natural Science Foundation of China(82072051,81771964,81803450,51973060,81772317,81871753)National Key R&D Program of China(2018YFE0201500)+3 种基金funded by the Special Project of Clinical Research of Health Industry of Shanghai Municipal Health Commission(No.201940178,China)by the Scientific Research Project of Hongkou District Health Committee of Shanghai(No.2002—17,China)by the Clinical Research Project of Wu Jieping Medical Foundation(No.320.6750.2020-18-2,China)by the Research Project of Shanghai Fourth People’s Hospital(sykyqd 00701&00702,China)。
文摘Tumor-associated macrophages(TAMs),one of the dominating constituents of tumor microenvironment,are important contributors to cancer progression and treatment resistance.Therefore,regulation of TAMs polarization from M2 phenotype towards M1 phenotype has emerged as a new strategy for tumor immunotherapy.Herein,we successfully initiated antitumor immunotherapy by inhibiting TAMs M2 polarization via autophagy intervention with polyethylene glycol-conjugated gold nanoparticles(PEG-Au NPs).PEG-Au NPs suppressed TAMs M2 polarization in both in vitro and in vivo models,elicited antitumor immunotherapy and inhibited subcutaneous tumor growth in mice.As demonstrated by the m RFP-GFP-LC3 assay and analyzing the autophagy-related proteins(LC3,beclin1 and P62),PEGAu NPs induced autophagic flux inhibition in TAMs,which is attributed to the PEG-Au NPs induced lysosome alkalization and membrane permeabilization.Besides,TAMs were prone to polarize towards M2phenotype following autophagy activation,whereas inhibition of autophagic flux could reduce the M2polarization of TAMs.Our results revealed a mechanism underlying PEG-Au NPs induced antitumor immunotherapy,where PEG-Au NPs reduce TAMs M2 polarization via induction of lysosome dysfunction and autophagic flux inhibition.This study elucidated the biological effects of nanomaterials on TAMs polarization and provided insight into harnessing the intrinsic immunomodulation capacity of nanomaterials for effective cancer treatment.
基金NationalNatural Science Foundation of China:National Science Foundation for ExcellentYoung Scholars,Grant/Award Number:32122052NationalNatural Sci-ence Foundation of China:NationalNat-ural Science FoundationRegional Inno-vation and Development,Grant/Award Number:U19A2003NationalNatural Science Foundation ofChina:National Science Foundation forYoung Scholars,Grant/Award Number:81902662。
文摘Background:Understanding how the tumor microenvironment is shaped by various factors is important for the development of new therapeutic strategies.Tumor cells often undergo spontaneous apoptotic cell death in tumor microen-vironment,these apoptotic cells are histologically co-localized with immunosup-pressive macrophages.However,the mechanism by which tumor cell apoptosis modulates macrophage polarization is not fully understood.In this study,we aimed to explore the tumor promoting effects of apoptotic tumor cells and the signal pathways involved.Methods:Apoptotic cells and macrophages in tumors were detected by immunohistochemical staining.Morphological analysis was performed with Giemsa staining.Lipids generated from apoptotic cells were detected by liq-uid chromatography-mass spectrometry.Phosphatidylserine-containing lipo-somes were prepared to mimic apoptotic cells.The expression of protein was determined by real-time PCR,immunohistochemistry enzyme-linked immunosorbent assay and Western blotting.Mouse malignant ascites and subcu-taneous tumor models were designed for in vivo analysis.Transgenic mice with specific genes knocked out and inhibitors specific to certain proteins were used for the mechanistic studies.Results:The location and the number of apoptotic cells were correlated with that of macrophages in several types of carcinomas.Phosphatidylserine,a lipid molecule generated in apoptotic cells,induced polarization and accumulation of M2-like macrophages in vivo and in vitro.Moreover,sustained administration of phosphoserine promoted tumor growth in the malignant ascites and subcuta-neous tumor models.Further analyses suggested that phosphoserine induced a M2-like phenotype in macrophages,which was related to the activation of phosphoserine receptors including T-cell immunoglobin mucin 4(TIM4)and the FAK-SRC-STAT3 signaling pathway as well as elevated the expression of the histone demethylase Jumonji domain-containing protein 3(JMJD3).Adminis-tration of specific inhibitors of these pathways could reduce tumor progression.Conclusions:This study suggest that apoptotic cell-generated phosphoserine might be a notable signal for immunosuppressive macrophages in tumors,and the related pathways might be potential therapeutic targets for cancer therapy.
基金supported by the Integrated Project of Major Research Plan of National Natural Science Foundation of China(92249303)Key Project of the National Natural Science Foundation of China(82230071)National Natural Science Foundation of China(32101084,82202344).
文摘Diabetes mellitus is a chronically inflamed disease that predisposes to delayed fracture healing.Macrophages play a key role in the process of fracture healing by undergoing polarization into either M1 or M2 subtypes,which respectively exhibit pro-inflammatory or anti-inflammatory functions.Therefore,modulation of macrophage polarization to the M2 subtype is beneficial for fracture healing.Exosomes perform an important role in improving the osteoimmune microenvironment due to their extremely low immunogenicity and high bioactivity.In this study,we extracted the M2-exosomes and used them to intervene the bone repair in diabetic fractures.The results showed that M2-exosomes significantly modulate the osteoimmune microenvironment by decreasing the proportion of M1 macrophages,thereby accelerating diabetic fracture healing.We further confirmed that M2-exosomes induced the conversion of M1 macrophages into M2 macrophages by stimulating the PI3K/AKT pathway.Our study offers a fresh perspective and a potential therapeutic approach for M2-exosomes to improve diabetic fracture healing.
基金supported by the National Science Foundation of China(NSFC 81802196,81572129,81872877,91853109,and 81772335)Key Program of NSFC(81730067,China)+3 种基金Special Program of Chinese Academy of Science(XDA16020805,China)Jiangsu Provincial Key Medical Center Foundation(China)Jiangsu Provincial Medical Outstanding Talent Foundation(China)Jiangsu Provincial Key Medical Talent Foundation(China)。
文摘Osteoarthritis(OA),in which M1 macrophage polarization in the synovium exacerbates disease progression,is a major cause of cartilage degeneration and functional disabilities.Therapeutic strategies of OA designed to interfere with the polarization of macrophages have rarely been reported.Here,we report that SHP099,as an allosteric inhibitor of src-homology 2-containing protein tyrosine phosphatase 2(SHP2),attenuated osteoarthritis progression by inhibiting M1 macrophage polarization.We demonstrated that M1 macrophage polarization was accompanied by the overexpression of SHP2 in the synovial tissues of OA patients and OA model mice.Compared to wild-type(WT)mice,myeloid lineage conditional Shp2 knockout(c KO)mice showed decreased M1 macrophage polarization and attenuated severity of synovitis,an elevated expression of cartilage phenotype protein collagen II(COL2),and a decreased expression of cartilage degradation markers collagen X(COL10)and matrix metalloproteinase3(MMP3)in OA cartilage.Further mechanistic analysis showed that SHP099 inhibited lipopolysaccharide(LPS)-induced Toll-like receptor(TLR)signaling mediated by nuclear factor kappa B(NF-κB)and PI3K—AKT signaling.Moreover,intra-articular injection of SHP099 also significantly attenuated OA progression,including joint synovitis and cartilage damage.These results indicated that allosteric inhibition of SHP2 might be a promising therapeutic strategy for the treatment of OA.
