During liver injury,intrahepatic macrophage compartment is augmented by circulating monocytes that infiltrate the liver driven by C-C motif chemokine ligand/C-C motif chemokine receptor(CCL/CCR)axis including CCL1‒CCR...During liver injury,intrahepatic macrophage compartment is augmented by circulating monocytes that infiltrate the liver driven by C-C motif chemokine ligand/C-C motif chemokine receptor(CCL/CCR)axis including CCL1‒CCR8 axis,thereby contributing to liver inflammation.Numerous small molecular receptor antagonists,including R243,have been developed for targeting CCR8;however,these agents face challenges in clinical translation,potentially attributed to their poor pharmacokinetic profiles,lack of target specificity,and potential adverse effects.In this study,we designed four CCR8 antagonizing peptides(AP8i-AP8iv)and performed molecular characterization in silico and therapeutic investigation in vitro and in vivo.Based on in silico docking,molecular dynamic simulation using homology build model and in-vitro(competitive)binding studies,AP8ii(YEWRFYHG)evidenced highly favorable and selective interactions at the CCR8-active site.AP8ii inhibited CCL1-driven chemotaxis and LPS/IFNg-induced pro-inflammatory activation of monocytes-macrophages in vitro.In a CCl4-induced acute liver injury mouse model,AP8ii treatment decreased intrahepatic infiltration of circulating monocytes.Moreover,AP8ii reduced liver inflammation,as indicated by decreased F4/80,IL6 and iNOS expression,diminished ALT levels,and attenuated fibrosis,as indicated by reduced collagen-I expression.In conclusion,we report a novel CCR8-antagonizing peptide that inhibited CCL1-driven intrahepatic monocytes infiltration and differentiation into pro-inflammatory phenotype,consequently ameliorating liver inflammation and fibrogenesis in an acute liver injury mouse model.展开更多
Brain tumors such as glioblastomas are resistant to immune checkpoint blockade therapy,largely due to limited T cell infiltration in the tumors.Here,we show that mice bearing intracranial tumors exhibit systemic immun...Brain tumors such as glioblastomas are resistant to immune checkpoint blockade therapy,largely due to limited T cell infiltration in the tumors.Here,we show that mice bearing intracranial tumors exhibit systemic immunosuppression and T cell sequestration in bone marrow,leading to reduced T cell infiltration in brain tumors.Elevated plasma corticosterone drives the T cell sequestration via glucocorticoid receptors in tumor-bearing mice.Immunosuppression mediated by glucocorticoid-induced T cell dynamics and the subsequent tumor growth promotion can be abrogated by adrenalectomy,the administration of glucocorticoid activation inhibitors or glucocorticoid receptor antagonists,and in mice with T cell-specific deletion of glucocorticoid receptor.CCR8 expression in T cells is increased in tumor-bearing mice in a glucocorticoid receptor-dependent manner.Additionally,chemokines CCL1 and CCL8,the ligands for CCR8,are highly expressed in bone marrow immune cells in tumor-bearing mice to recruit T cells.These findings suggested that brain tumor-induced glucocorticoid surge and CCR8 upregulation in T cells lead to T cell sequestration in bone marrow,impairing the anti-tumor immune response.Targeting the glucocorticoid receptor-CCR8 axis may offer a promising immunotherapeutic approach for the treatment of intracranial tumors.展开更多
The enrichment of regulatory T cells(Tregs)in the tumour microenvironment(TME)has been recognized as one of the major factors in the initiation and development of resistance to immune checkpoint inhibitors.C–C motif ...The enrichment of regulatory T cells(Tregs)in the tumour microenvironment(TME)has been recognized as one of the major factors in the initiation and development of resistance to immune checkpoint inhibitors.C–C motif chemokine receptor 8(CCR8),a marker of activated suppressive Tregs,has a significant impact on the functions of Tregs in the TME.However,the regulatory mechanism of CCR8 in Tregs remains unclear.Here,we revealed that a high level of TNF-αin the colorectal cancer(CRC)microenvironment upregulated CCR8 expression in Tregs via the TNFR2/NF-κB signalling pathway and the FOXP3 transcription factor.Furthermore,in both anti-programmed cell death protein 1(anti-PD1)-responsive and anti-PD1-unresponsive tumour models,PD1 blockade induced CCR8^(+)Treg infiltration.In both models,Tnfr2 depletion or TNFR2 blockade suppressed tumour progression by reducing CCR8+Treg infiltration and thus augmented the efficacy of anti-PD1 therapy.Finally,we identified that TNFR2^(+)CCR8^(+)Tregs but not total Tregs were positively correlated with adverse prognosis in patients with CRC and gastric cancer.Our work reveals the regulatory mechanisms of CCR8 in Tregs and identifies TNFR2 as a promising target for immunotherapy.展开更多
文摘During liver injury,intrahepatic macrophage compartment is augmented by circulating monocytes that infiltrate the liver driven by C-C motif chemokine ligand/C-C motif chemokine receptor(CCL/CCR)axis including CCL1‒CCR8 axis,thereby contributing to liver inflammation.Numerous small molecular receptor antagonists,including R243,have been developed for targeting CCR8;however,these agents face challenges in clinical translation,potentially attributed to their poor pharmacokinetic profiles,lack of target specificity,and potential adverse effects.In this study,we designed four CCR8 antagonizing peptides(AP8i-AP8iv)and performed molecular characterization in silico and therapeutic investigation in vitro and in vivo.Based on in silico docking,molecular dynamic simulation using homology build model and in-vitro(competitive)binding studies,AP8ii(YEWRFYHG)evidenced highly favorable and selective interactions at the CCR8-active site.AP8ii inhibited CCL1-driven chemotaxis and LPS/IFNg-induced pro-inflammatory activation of monocytes-macrophages in vitro.In a CCl4-induced acute liver injury mouse model,AP8ii treatment decreased intrahepatic infiltration of circulating monocytes.Moreover,AP8ii reduced liver inflammation,as indicated by decreased F4/80,IL6 and iNOS expression,diminished ALT levels,and attenuated fibrosis,as indicated by reduced collagen-I expression.In conclusion,we report a novel CCR8-antagonizing peptide that inhibited CCL1-driven intrahepatic monocytes infiltration and differentiation into pro-inflammatory phenotype,consequently ameliorating liver inflammation and fibrogenesis in an acute liver injury mouse model.
基金supported by grants from the National Key R&D Program of China(2022YFA0807300 and 2021YFA1100600)the National Natural Science Foundation of China(81930085 and 32150710523)the Jiangsu Province International Joint Laboratory for Regenerative Medicine Fund and Suzhou Science and Technology Bureau(ZXL2021440,SWY202202 and SYS2020087).
文摘Brain tumors such as glioblastomas are resistant to immune checkpoint blockade therapy,largely due to limited T cell infiltration in the tumors.Here,we show that mice bearing intracranial tumors exhibit systemic immunosuppression and T cell sequestration in bone marrow,leading to reduced T cell infiltration in brain tumors.Elevated plasma corticosterone drives the T cell sequestration via glucocorticoid receptors in tumor-bearing mice.Immunosuppression mediated by glucocorticoid-induced T cell dynamics and the subsequent tumor growth promotion can be abrogated by adrenalectomy,the administration of glucocorticoid activation inhibitors or glucocorticoid receptor antagonists,and in mice with T cell-specific deletion of glucocorticoid receptor.CCR8 expression in T cells is increased in tumor-bearing mice in a glucocorticoid receptor-dependent manner.Additionally,chemokines CCL1 and CCL8,the ligands for CCR8,are highly expressed in bone marrow immune cells in tumor-bearing mice to recruit T cells.These findings suggested that brain tumor-induced glucocorticoid surge and CCR8 upregulation in T cells lead to T cell sequestration in bone marrow,impairing the anti-tumor immune response.Targeting the glucocorticoid receptor-CCR8 axis may offer a promising immunotherapeutic approach for the treatment of intracranial tumors.
基金National Natural Science Foundation of China(31872740,31961133011,32070878,and 81830051)Innovative Research Team of High-level Local Universities in Shanghai(SHSMU-ZDCX20210601).
文摘The enrichment of regulatory T cells(Tregs)in the tumour microenvironment(TME)has been recognized as one of the major factors in the initiation and development of resistance to immune checkpoint inhibitors.C–C motif chemokine receptor 8(CCR8),a marker of activated suppressive Tregs,has a significant impact on the functions of Tregs in the TME.However,the regulatory mechanism of CCR8 in Tregs remains unclear.Here,we revealed that a high level of TNF-αin the colorectal cancer(CRC)microenvironment upregulated CCR8 expression in Tregs via the TNFR2/NF-κB signalling pathway and the FOXP3 transcription factor.Furthermore,in both anti-programmed cell death protein 1(anti-PD1)-responsive and anti-PD1-unresponsive tumour models,PD1 blockade induced CCR8^(+)Treg infiltration.In both models,Tnfr2 depletion or TNFR2 blockade suppressed tumour progression by reducing CCR8+Treg infiltration and thus augmented the efficacy of anti-PD1 therapy.Finally,we identified that TNFR2^(+)CCR8^(+)Tregs but not total Tregs were positively correlated with adverse prognosis in patients with CRC and gastric cancer.Our work reveals the regulatory mechanisms of CCR8 in Tregs and identifies TNFR2 as a promising target for immunotherapy.
