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
Immunological evasion is one of the defining characteristics of cancers,as the immune modification of an immune checkpoint(IC)confers immune evasion capabilities to tumor cells.Multiple ICs,such as programmed cell dea...Immunological evasion is one of the defining characteristics of cancers,as the immune modification of an immune checkpoint(IC)confers immune evasion capabilities to tumor cells.Multiple ICs,such as programmed cell death protein-1(PD-1)and cytotoxic T-lymphocyte-associated antigen-4(CTLA-4),can bind to their respective receptors and reduce tumor immunity in a variety of ways,including blocking immune cell activation signals.IC blockade(ICB)therapies targeting these checkpoint molecules have demonstrated significant clinical benefits.This is because antibody-based IC inhibitors and a variety of specific small molecule inhibitors can inhibit key oncogenic signaling pathways and induce durable tumor remission in patients with a variety of cancers.Deciphering the roles and regulatory mechanisms of these IC molecules will provide crucial theoretical guidance for clinical treatment.In this review,we summarize the current knowledge on the functional and regulatory mechanisms of these IC molecules at multiple levels,including epigenetic regulation,transcriptional regulation,and post-translational modifications.In addition,we provide a summary of the medications targeting various nodes in the regulatory pathway,and highlight the potential of newly identified IC molecules,focusing on their potential implications for cancer diagnostics and immunotherapy.展开更多
Among many factors known to alter the outcomes of T cell receptor(TCR)-induced proximal signaling,the role of human germline variants in dictating the individuality of the anti-tumor CD8 T cell response has remained c...Among many factors known to alter the outcomes of T cell receptor(TCR)-induced proximal signaling,the role of human germline variants in dictating the individuality of the anti-tumor CD8 T cell response has remained challenging to address.Here,we describe a convenient strategy for molecular and functional characterization of phosphotyrosine-altering non-synonymous single nucleotide variations(pTyr-SNVs)that directly impact TCR-induced proximal phosphotyrosine motif-based signaling pathways.We devise an experimental co-cultivation set-up comprising a C57BL/6 mouse-derived metastatic melanoma cell line engineered to constitutively present ovalbumin(OVA)antigens and retrovirally engineered syngeneic major histocompatibility complex(MHC)Class I restricted OVA TCR-transgenic CD8 T cells(OT-I).Using the synthetic version of pTyr-SNV rs1178800678-G/T-encoding integrin alpha 4(ITGA4)p.S1027I variant as a prototype,we show that under identical TCR stimulation conditions,genetically determined membrane-proximal immunoreceptor tyrosin activation motif(ITAM)results in increased tyrosine phosphorylation of 70 kDa zeta-chain-associated protein(ZAP70)and the levels of cytotoxic effector molecule granzyme B(GZMB),which in turn result in enhanced cytotoxic activity against metastatic melanoma cell line.This strategy paves the way for rapid molecular and functional characterization of anti-tumor immune response-linked germline pTyr-SNVs so as to improve our understanding of the genetic basis of individual-to-individual differences in anti-tumor CD8 T cell response.展开更多
At the onset of an infection early defense systems, such as complement, get into action. Specialized leukocytes (white blood cells) of the innate immune system, including monocytes, macrophages, and neutrophils also p...At the onset of an infection early defense systems, such as complement, get into action. Specialized leukocytes (white blood cells) of the innate immune system, including monocytes, macrophages, and neutrophils also participate as a first line of defense against infections. These early responses are rapid but not very specific and are usually not enough to clear completely many infections. The adaptive immune system is also needed to finish the job against many microorganisms. Antibody molecules, produced during the adaptive immune response, are crucial for preventing recurrent infections. Although, IgG antibodies are essential for controlling infections, these molecules do not directly damage the microorganisms they recognize. Today, it is established that leukocytes of the innate immune system are responsible for the protective effects of these antibodies. IgG molecules bind to their cognate antigens and are in turn recognized by specific receptors (Fcγ receptors) on the membrane of leukocytes. Crosslinking these receptors on the surface of leukocytes leads to activation of several effector cell functions. These effector functions are geared toward the destruction of microbial pathogens and the induction of an inflammatory state that is beneficial during infections. However, in autoimmune diseases, antibodies can direct these effector functions against normal tissues and cause severe tissue damage. In recent years, several factors that can modulate the IgG-FcγR interaction have been elucidated. In this review, we describe the main types of Fcγ receptors, and our current view of how antibody variants interact with these receptors to initiate different cell responses. In addition, new findings on the signaling role of individual Fcγ receptors are also discussed.展开更多
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 by the National Key Research and Development Program of China(No.2021YFC2700903)the National Natural Science Foundation of China(Nos.81672791 and 81872300)+2 种基金the Zhejiang Provincial Natural Science Fund for Distinguished Young Scholars of China(No.LR18C060002)the Huadong Medicine Joint Funds of the Zhejiang Provincial Natural Science Foundation of China(No.LHDMY22H160006)the ZJU-QILU Joint Research Institute and Qilu Group.
文摘Immunological evasion is one of the defining characteristics of cancers,as the immune modification of an immune checkpoint(IC)confers immune evasion capabilities to tumor cells.Multiple ICs,such as programmed cell death protein-1(PD-1)and cytotoxic T-lymphocyte-associated antigen-4(CTLA-4),can bind to their respective receptors and reduce tumor immunity in a variety of ways,including blocking immune cell activation signals.IC blockade(ICB)therapies targeting these checkpoint molecules have demonstrated significant clinical benefits.This is because antibody-based IC inhibitors and a variety of specific small molecule inhibitors can inhibit key oncogenic signaling pathways and induce durable tumor remission in patients with a variety of cancers.Deciphering the roles and regulatory mechanisms of these IC molecules will provide crucial theoretical guidance for clinical treatment.In this review,we summarize the current knowledge on the functional and regulatory mechanisms of these IC molecules at multiple levels,including epigenetic regulation,transcriptional regulation,and post-translational modifications.In addition,we provide a summary of the medications targeting various nodes in the regulatory pathway,and highlight the potential of newly identified IC molecules,focusing on their potential implications for cancer diagnostics and immunotherapy.
文摘Among many factors known to alter the outcomes of T cell receptor(TCR)-induced proximal signaling,the role of human germline variants in dictating the individuality of the anti-tumor CD8 T cell response has remained challenging to address.Here,we describe a convenient strategy for molecular and functional characterization of phosphotyrosine-altering non-synonymous single nucleotide variations(pTyr-SNVs)that directly impact TCR-induced proximal phosphotyrosine motif-based signaling pathways.We devise an experimental co-cultivation set-up comprising a C57BL/6 mouse-derived metastatic melanoma cell line engineered to constitutively present ovalbumin(OVA)antigens and retrovirally engineered syngeneic major histocompatibility complex(MHC)Class I restricted OVA TCR-transgenic CD8 T cells(OT-I).Using the synthetic version of pTyr-SNV rs1178800678-G/T-encoding integrin alpha 4(ITGA4)p.S1027I variant as a prototype,we show that under identical TCR stimulation conditions,genetically determined membrane-proximal immunoreceptor tyrosin activation motif(ITAM)results in increased tyrosine phosphorylation of 70 kDa zeta-chain-associated protein(ZAP70)and the levels of cytotoxic effector molecule granzyme B(GZMB),which in turn result in enhanced cytotoxic activity against metastatic melanoma cell line.This strategy paves the way for rapid molecular and functional characterization of anti-tumor immune response-linked germline pTyr-SNVs so as to improve our understanding of the genetic basis of individual-to-individual differences in anti-tumor CD8 T cell response.
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At the onset of an infection early defense systems, such as complement, get into action. Specialized leukocytes (white blood cells) of the innate immune system, including monocytes, macrophages, and neutrophils also participate as a first line of defense against infections. These early responses are rapid but not very specific and are usually not enough to clear completely many infections. The adaptive immune system is also needed to finish the job against many microorganisms. Antibody molecules, produced during the adaptive immune response, are crucial for preventing recurrent infections. Although, IgG antibodies are essential for controlling infections, these molecules do not directly damage the microorganisms they recognize. Today, it is established that leukocytes of the innate immune system are responsible for the protective effects of these antibodies. IgG molecules bind to their cognate antigens and are in turn recognized by specific receptors (Fcγ receptors) on the membrane of leukocytes. Crosslinking these receptors on the surface of leukocytes leads to activation of several effector cell functions. These effector functions are geared toward the destruction of microbial pathogens and the induction of an inflammatory state that is beneficial during infections. However, in autoimmune diseases, antibodies can direct these effector functions against normal tissues and cause severe tissue damage. In recent years, several factors that can modulate the IgG-FcγR interaction have been elucidated. In this review, we describe the main types of Fcγ receptors, and our current view of how antibody variants interact with these receptors to initiate different cell responses. In addition, new findings on the signaling role of individual Fcγ receptors are also discussed.
