Spinal cord injury causes accumulation of a large number of leukocytes at the lesion site where they contribute to excessive inflammation.Overproduced chemokines are responsible for the migratory process of the leukoc...Spinal cord injury causes accumulation of a large number of leukocytes at the lesion site where they contribute to excessive inflammation.Overproduced chemokines are responsible for the migratory process of the leukocytes,but the regulatory mechanism underlying the production of chemokines from resident cells of the spinal cord has not been fully elucidated.We examined the protein levels of macrophage migration inhibitory factor and chemokine C-C motif chemokine ligand 2 in a spinal cord contusion model at different time points following spinal cord injury.The elevation of macrophage migration inhibitory factor at the lesion site coincided with the increase of chemokine C-C motif chemokine ligand 2 abundance in astrocytes.Stimulation of primary cultured astrocytes with different concentrations of macrophage migration inhibitory factor recombinant protein induced chemokine C-C motif chemokine ligand 2 production from the cells,and the macrophage migration inhibitory factor inhibitor 4-iodo-6-phenylpyrimidine attenuated the stimulatory effect.Further investigation into the underlying mechanism on macrophage migration inhibitory factor-mediated astrocytic production of chemokine C-C motif chemokine ligand 2 revealed that macrophage migration inhibitory factor activated intracellular JNK signaling through binding with CD74 receptor.Administration of the macrophage migration inhibitory factor inhibitor 4-iodo-6-phenylpyrimidine following spinal cord injury resulted in the reduction of chemokine C-C motif chemokine ligand 2-recruited microglia/macrophages at the lesion site and remarkably improved the hindlimb locomotor function of rats.Our results have provided insights into the functions of astrocyte-activated chemokines in the recruitment of leukocytes and may be beneficial to develop interventions targeting chemokine C-C motif chemokine ligand 2 for neuroinflammation after spinal cord injury.展开更多
Osteoclast differentiation depends on receptor activator of nuclear factor-κB(RANK) signaling,which can be divided into triggering,amplifying and targeting phases based on how active the master regulator nuclear fact...Osteoclast differentiation depends on receptor activator of nuclear factor-κB(RANK) signaling,which can be divided into triggering,amplifying and targeting phases based on how active the master regulator nuclear factor of activated T-cells cytoplasmic 1(NFATc1) is. The triggering phase is characterized by immediateearly RANK signaling induced by RANK ligand(RANKL) stimulation mediated by three adaptor proteins,tumor necrosis factor receptor-associated factor 6,Grb-2-associated binder-2 and phospholipase C(PLC)γ2,leading to activation of IκB kinase,mitogen-activated protein kinases and the transcription factors nuclear factor(NF)-κB and activator protein-1(AP-1). Mice lacking NF-κB p50/p52 or the AP-1 subunit c-Fos(encoded by Fos) exhibit severe osteopetrosis due to a differentiation block in the osteoclast lineage. The amplification phase occurs about 24 h later in a RANKLinduced osteoclastogenic culture when Ca2+ oscillation starts and the transcription factor NFATc1 is abundantly produced. In addition to Ca2+ oscillation-dependent nuclear translocation and transcriptional auto-induction of NFATc1,a Ca2+ oscillation-independent,osteoblastdependent mechanism stabilizes NFATc1 protein in dif-ferentiating osteoclasts. Osteoclast precursors lacking PLCγ2,inositol-1,4,5-trisphosphate receptors,regulator of G-protein signaling 10,or NFATc1 show an impaired transition from the triggering to amplifying phases. The final targeting phase is mediated by activation of numerous NFATc1 target genes responsible for cell-cell fusion and regulation of bone-resorptive function. This review focuses on molecular mechanisms for each of the three phases of RANK signaling during osteoclast differentiation.展开更多
Inhibitory leukocyte immunoglobulin-like receptors(LILRB1-5) signal through immunoreceptor tyrosine-based inhibitory motifs(ITIMs) in their intracellular domains and recruit phosphatases protein tyrosine phosphatase, ...Inhibitory leukocyte immunoglobulin-like receptors(LILRB1-5) signal through immunoreceptor tyrosine-based inhibitory motifs(ITIMs) in their intracellular domains and recruit phosphatases protein tyrosine phosphatase, non-receptor type 6(PTPN6, SHP-1), protein tyrosine phosphatase, non-receptor type 6(PTPN6, SHP-2), or Src homology 2 domain containing inositol phosphatase(SHIP) to negatively regulate immune cell activation. These receptors are known to play important regulatory roles in immune and neuronal functions. Recent studies demonstrated that several of these receptors are expressed by cancer cells. Importantly, they may directly regulate development, drug resistance, and relapse of cancer, and the activity of cancer stem cells. Although counterintuitive, these findings are consistent with the generally immune-suppressive and thus tumor-promoting roles of the inhibitory receptors in the immune system. This review focuses on the ligands, expression pattern, signaling, and function of LILRB family in the context of cancer development. Because inhibition of the signaling of certain LILRBs directly blocks cancer growth and stimulates immunity that may suppress tumorigenesis, but does not disturb normal development, LILRB signaling pathways may represent ideal targets for treating hematological malignancies and perhaps other tumors.展开更多
Plasmacytoid dendritic cells(pDCs),also known as type I interferon(IFN)-producing cells,are specialized immune cells characterized by their extraordinary capabilities of mounting rapid and massive type I IFN response ...Plasmacytoid dendritic cells(pDCs),also known as type I interferon(IFN)-producing cells,are specialized immune cells characterized by their extraordinary capabilities of mounting rapid and massive type I IFN response to nu-cleic acids derived from virus,bacteria or dead cells.PDCs selectively express endosomal Toll-like receptor(TLR)7 and TLR9,which sense viral RNA and DNA re-spectively.Following type I IFN and cytokine responses,pDCs differentiate into antigen presenting cells and ac-quire the ability to regulate T cell-mediated adaptive immunity.The functions of pDCs have been implicated not only in antiviral innate immunity but also in immune tolerance,inflammation and tumor microenvironments.In this review,we will focus on TLR7/9 signaling and their regulation by pDC-specific receptors.展开更多
基金supported by the China Postdoctoral Science Foundation,No.2020M681689(to YMH)the Basic Scientific Research Projects of Nantong,Nos.JC2020015(to HX)and JC2020041(to YMH)。
文摘Spinal cord injury causes accumulation of a large number of leukocytes at the lesion site where they contribute to excessive inflammation.Overproduced chemokines are responsible for the migratory process of the leukocytes,but the regulatory mechanism underlying the production of chemokines from resident cells of the spinal cord has not been fully elucidated.We examined the protein levels of macrophage migration inhibitory factor and chemokine C-C motif chemokine ligand 2 in a spinal cord contusion model at different time points following spinal cord injury.The elevation of macrophage migration inhibitory factor at the lesion site coincided with the increase of chemokine C-C motif chemokine ligand 2 abundance in astrocytes.Stimulation of primary cultured astrocytes with different concentrations of macrophage migration inhibitory factor recombinant protein induced chemokine C-C motif chemokine ligand 2 production from the cells,and the macrophage migration inhibitory factor inhibitor 4-iodo-6-phenylpyrimidine attenuated the stimulatory effect.Further investigation into the underlying mechanism on macrophage migration inhibitory factor-mediated astrocytic production of chemokine C-C motif chemokine ligand 2 revealed that macrophage migration inhibitory factor activated intracellular JNK signaling through binding with CD74 receptor.Administration of the macrophage migration inhibitory factor inhibitor 4-iodo-6-phenylpyrimidine following spinal cord injury resulted in the reduction of chemokine C-C motif chemokine ligand 2-recruited microglia/macrophages at the lesion site and remarkably improved the hindlimb locomotor function of rats.Our results have provided insights into the functions of astrocyte-activated chemokines in the recruitment of leukocytes and may be beneficial to develop interventions targeting chemokine C-C motif chemokine ligand 2 for neuroinflammation after spinal cord injury.
基金Supported by Grants from MEXT Japan,No.23790265(to Kuroda Y)and No.21390425(to Matsuo K)
文摘Osteoclast differentiation depends on receptor activator of nuclear factor-κB(RANK) signaling,which can be divided into triggering,amplifying and targeting phases based on how active the master regulator nuclear factor of activated T-cells cytoplasmic 1(NFATc1) is. The triggering phase is characterized by immediateearly RANK signaling induced by RANK ligand(RANKL) stimulation mediated by three adaptor proteins,tumor necrosis factor receptor-associated factor 6,Grb-2-associated binder-2 and phospholipase C(PLC)γ2,leading to activation of IκB kinase,mitogen-activated protein kinases and the transcription factors nuclear factor(NF)-κB and activator protein-1(AP-1). Mice lacking NF-κB p50/p52 or the AP-1 subunit c-Fos(encoded by Fos) exhibit severe osteopetrosis due to a differentiation block in the osteoclast lineage. The amplification phase occurs about 24 h later in a RANKLinduced osteoclastogenic culture when Ca2+ oscillation starts and the transcription factor NFATc1 is abundantly produced. In addition to Ca2+ oscillation-dependent nuclear translocation and transcriptional auto-induction of NFATc1,a Ca2+ oscillation-independent,osteoblastdependent mechanism stabilizes NFATc1 protein in dif-ferentiating osteoclasts. Osteoclast precursors lacking PLCγ2,inositol-1,4,5-trisphosphate receptors,regulator of G-protein signaling 10,or NFATc1 show an impaired transition from the triggering to amplifying phases. The final targeting phase is mediated by activation of numerous NFATc1 target genes responsible for cell-cell fusion and regulation of bone-resorptive function. This review focuses on molecular mechanisms for each of the three phases of RANK signaling during osteoclast differentiation.
基金supported b y the Na tional In stitu te o f Health(1R01CA172268)the Leukemia&Lymphoma Society(1024-14+7 种基金TRP-6024-14)the Robert A.Welch Foundation(I-1834)the Cancer Prevention and Research Institute of Texas(RP140402 and DP150056)the Innovation Program of Shanghai Municipal Education Commission(13G20)the Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learningthe National Natural Science Foundation of China(813706548142200181471524)
文摘Inhibitory leukocyte immunoglobulin-like receptors(LILRB1-5) signal through immunoreceptor tyrosine-based inhibitory motifs(ITIMs) in their intracellular domains and recruit phosphatases protein tyrosine phosphatase, non-receptor type 6(PTPN6, SHP-1), protein tyrosine phosphatase, non-receptor type 6(PTPN6, SHP-2), or Src homology 2 domain containing inositol phosphatase(SHIP) to negatively regulate immune cell activation. These receptors are known to play important regulatory roles in immune and neuronal functions. Recent studies demonstrated that several of these receptors are expressed by cancer cells. Importantly, they may directly regulate development, drug resistance, and relapse of cancer, and the activity of cancer stem cells. Although counterintuitive, these findings are consistent with the generally immune-suppressive and thus tumor-promoting roles of the inhibitory receptors in the immune system. This review focuses on the ligands, expression pattern, signaling, and function of LILRB family in the context of cancer development. Because inhibition of the signaling of certain LILRBs directly blocks cancer growth and stimulates immunity that may suppress tumorigenesis, but does not disturb normal development, LILRB signaling pathways may represent ideal targets for treating hematological malignancies and perhaps other tumors.
文摘目的:初步探讨慢性淋巴细胞白血病(chronic lymphocytic leukemia,CLL)患者外周血共抑制分子T细胞免疫球蛋白和ITIM结构域(T-cell immunoglobulin and immunoreceptor tyrosine-based inhibitory motif domain,TIGIT)和程序性细胞死亡受体1(programmed cell death protein 1,PD-1)在Tfh细胞上的表达变化特点及临床意义。方法:采用流式细胞术检测50例CLL患者、36例非CLL的慢性B淋巴细胞增殖疾病患者和30例健康者外周血Tfh细胞百分比和Tfh细胞上PD-1和TIGIT的水平,比较3组受试者的差异。分析CLL患者TIGIT+PD-1+Tfh细胞百分比与IPI评分分层的关系,以及与免疫球蛋白的相关性。结果:(1)与对照组比较,初诊CLL患者Tfh、PD-1+Tfh、TIGIT+Tfh、TIGIT+PD-1+Tfh、TIGIT+PD-1-Tfh和TIGIT-PD-1+Tfh细胞百分比明显增高,差异有统计学意义(P<0.05)。(2)TIGIT+PD-1+Tfh细胞在CLL-IPI预后分层低危组、中危组、高危组、极高危组比较分析结果,组间和组内两两比较差异均有统计学意义(P<0.05),随着预后分层增加TIGIT+PD-1+Tfh细胞水平逐渐增加。(3)受试者工作特征曲线结果显示,TIGIT+PD-1+Tfh细胞在CLL患者和非CLL患者的鉴别诊断中具有一定的诊断价值(P<0.05)。(4)Logistic回归分析显示,TIGIT+PD-1+Tfh细胞百分比是CLL发病的独立危险因素(P<0.05)。(5)CLL患者外周血中TIGIT+PD-1+Tfh与IgA、IgM、IgG均呈负相关(P<0.05)。结论:初诊CLL患者外周血TIGIT+PD-1+Tfh细胞百分比明显增加,Tfh细胞高表达共抑制分子TIGIT和PD-1参与CLL疾病的发生,并且与疾病的免疫球蛋白水平降低有关。
文摘Plasmacytoid dendritic cells(pDCs),also known as type I interferon(IFN)-producing cells,are specialized immune cells characterized by their extraordinary capabilities of mounting rapid and massive type I IFN response to nu-cleic acids derived from virus,bacteria or dead cells.PDCs selectively express endosomal Toll-like receptor(TLR)7 and TLR9,which sense viral RNA and DNA re-spectively.Following type I IFN and cytokine responses,pDCs differentiate into antigen presenting cells and ac-quire the ability to regulate T cell-mediated adaptive immunity.The functions of pDCs have been implicated not only in antiviral innate immunity but also in immune tolerance,inflammation and tumor microenvironments.In this review,we will focus on TLR7/9 signaling and their regulation by pDC-specific receptors.
