目的检测免疫性血小板减少症(ITP)患者外周血中CD8^+CD28^-调节性T细胞(Treg)、血小板特异性自身抗体、细胞因子的表达水平,分析其在ITP发病机制以及临床治疗中的意义。方法 73例ITP患者分为激素治疗组( n =42)、重组人粒血小板生成素(r...目的检测免疫性血小板减少症(ITP)患者外周血中CD8^+CD28^-调节性T细胞(Treg)、血小板特异性自身抗体、细胞因子的表达水平,分析其在ITP发病机制以及临床治疗中的意义。方法 73例ITP患者分为激素治疗组( n =42)、重组人粒血小板生成素(rhTPO)治疗组( n =31),并根据治疗效果分为有效组和无效组。流式细胞术检测患者治疗前后外周血CD8^+CD28^- Treg的表达,流式微球技术检测患者外周血血小板特异性自身抗体的表达。ELISA法检测患者治疗前后转化生长因子(TGF)-β1、白介素(IL)-10和干扰素(IFN)-γ表达水平。以30例健康体检者作为正常对照组。结果① 73例ITP患者治疗前CD8^+CD28^-Treg及细胞因子IL-10、TGF-β1的表达低于正常对照组,IFN-γ表达高于正常对照组( P <0.05),激素及rhTPO治疗后有效组CD8^+CD28^- Treg、IL-10、TGF-β1的表达均比治疗前显著上升,IFN-γ的表达较治疗前显著降低( P <0.05)。无效组CD8^+CD28^- Treg、IFN-γ、IL-10、TGF-β1的表达和治疗前相比均未有明显变化。②根据受试者工作特征曲线(ROC),激素组治疗前CD8^+CD28^-Treg的临界值为14.35,此时预测激素疗效的敏感性和特异性分别为66.7%和73.3%。27例有效者中小于14.35的有18例(66.7%),15例无效者中大于14.35的有11例(73.3%)。rhTPO组治疗前CD8^+CD28^-Treg的临界值为15.45,此时预测rhTPO疗效的敏感性和特异性分别为63.6%和88.9%。22例有效者中大于15.45的有14例(63.6%),9例无效者中小于15.45的有8例(88.9%)。③激素组抗血小板膜糖蛋白Ib(GPIb)抗体阳性患者18例,治疗后有效率44.4%,抗GPIb抗体阴性24例,有效率79.1%,两者比较差异有统计学意义( P <0.05)。结论 CD8^+CD28^- Treg及相关细胞因子的表达异常参与了ITP的发病,激素和rhTPO可能通过改变这种异常发挥作用。治疗前检测CD8^+CD28^-Treg有助于预测激素及rhTPO的疗效。抗GPIb抗体阳性可能是激素治疗不敏感的影响因素之一。展开更多
One important aspect of mesenchymal stromal cells （MSCs）-mediated immunomodulation is the recruitment and induction of regulatory T （Treg） cells. However, we do not yet know whether MSCs have similar effects on th...One important aspect of mesenchymal stromal cells （MSCs）-mediated immunomodulation is the recruitment and induction of regulatory T （Treg） cells. However, we do not yet know whether MSCs have similar effects on the other subsets of Treg cells. Herein, we studied the effects of MSCs on CD8＋CD28- Treg cells and found that the MSCs could not only increase the proportion of CD8＋CD28- T cells, but also enhance CD8＋CD28-T cells＇ ability of hampering naive CD4＋ T-cell proliferation and activation, decreasing the production of IFN-γ by activated CD4＋ T cells and inducing the apoptosis of activated CD4＋ T cells. Mechanistically, the MSCs affected the functions of the CD8＋CD28- T cells partially through moderate upregulating the expression of IL-10 and FasL. The MSCs had no distinct effect on the shift from CD8＋CD28＋ T cells to CD8＋CD28- T cells, but did increase the proportion of CD8＋CD28- T cells by reducing their rate of apoptosis. In summary, this study shows that MSCs can enhance the regulatory function of CD8＋CD28- Treg cells, shedding new light on MSCs-mediated immune regulation.展开更多
CD8^(+)T cells are regulatory T cells(Tregs)that suppress both alloimmunity and autoimmunity in many animal models.This class of regulatory cells includes the CD8^(+)CD28^(-),CD8^(+)CD103^(+),CD8^(+)FoxP3^(+)and CD8^(...CD8^(+)T cells are regulatory T cells(Tregs)that suppress both alloimmunity and autoimmunity in many animal models.This class of regulatory cells includes the CD8^(+)CD28^(-),CD8^(+)CD103^(+),CD8^(+)FoxP3^(+)and CD8^(+)CD122^(+)subsets.The mechanisms of action of these regulatory cells are not fully understood;however,the secretion of immunosuppressive cytokines,such as interleukin(IL)-4,IL-10 and transforming growth factor beta(TGF-β)as well as the direct killing of target cells via Fas L/Fas and the perforin/granzyme B pathways have been demonstrated in various models.Further studies are necessary to fully understand the mechanisms underlying the suppressive effects of Tregs and to provide experimental support for potential clinical trials.We recently observed that CD8^(+)CD122^(+)Tregs more potently suppressed allograft rejection compared to their CD4^(+)CD25^(+)counterparts,supporting the hypothesis that CD8^(+)Tregs may represent a new and promising Treg family that can be targeted to prevent allograft rejection in the clinic.In this review,we summarize the progress in the field during the past 7-10 years and discuss CD8^(+)Treg phenotypes,mechanisms of action,and their potential clinical applications;particularly in composite tissue transplants in burn and trauma patients.展开更多
Despite extensive studies on CD4^＋CD25^＋ regulatory T cells （Tregs） during the past decade, the progress on their clinical translation remains stagnant. Mounting evidence suggests that naturally occurring CD8^＋CD...Despite extensive studies on CD4^＋CD25^＋ regulatory T cells （Tregs） during the past decade, the progress on their clinical translation remains stagnant. Mounting evidence suggests that naturally occurring CD8^＋CD122^＋ T cells are also Tregs with the capacity to inhibit T-cell responses and suppress autoimmunity as well as alloimmunity. In fact, they are memory-like Tregs that resemble a central memory T cell （TcM） phenotype. The mechanisms underlying their suppression are still not well understood, although they may include IL-IO production. We have recently demonstrated that programmed death-1 （PD-1） expression distinguishes between regulatory and memory CD8^＋CD122^＋ T cells and that CD8^＋CD122^＋ Tregs undergo faster homeostatic proliferation and are more potent in the suppression of allograft rejection than conventional CD4^＋CD25^＋ Tregs. These findings may open a new line of investigation for accelerating effective Treg therapies in the clinic. In this review, we summarize the significant progress in this promising field of CD8^＋CD122^＋ Treg research and discuss their phenotypes, suppressive roles in autoimmunity and alloimmunity, functional requirements, mechanisms of action and potential applications in the clinic.展开更多
Autoreactive CD8^(+)T cells,which play an indispensable role inβcell destruction,represent an emerging target for the prevention of type 1 diabetes(T1D).Altered peptide ligands(APLs)can efficiently induce antigen-spe...Autoreactive CD8^(+)T cells,which play an indispensable role inβcell destruction,represent an emerging target for the prevention of type 1 diabetes(T1D).Altered peptide ligands(APLs)can efficiently induce antigen-specific T cells anergy,apoptosis or shifts in the immune response.Here,we found that HLA-A*0201-restricted CD8^(+)T cell responses against a primaryβ-cell autoantigen insulin epitope InsB15–14 were present in both NOD.β2m null.HHD NOD mice and T1D patients.We generated several APL candidates for InsB15–14 by residue substitution at the p6 position.Only H6F exhibited an inhibitory effect on mInsB1_(5–14)-specific CD8^(+)T cell responses in vitro.H6F treatment significantly reduced the T1D incidence,which was accompanied by diminished autoreactive CD8^(+)T cell responses to mInsB15-14,inhibited infiltration of CD8^(+)and CD4^(+)T cells in the pancreas and reduced pro-inflammatory cytokine production in pancreatic and splenic T cells in NOD.β2m^(null).HHD mice.Mechanistically,H6F treatment significantly augmented a tiny portion of CD8^(+)CD25^(+)Foxp3^(+)T cells in the spleen and especially in the pancreas.This subset exhibited typical Treg phenotypes and required peptide-specific restimulation to exert immunosuppressive activity.Therefore,this APL H6F may be a promising candidate with potential clinical application value for antigen-specific prevention of T1D.展开更多
文摘目的检测免疫性血小板减少症(ITP)患者外周血中CD8^+CD28^-调节性T细胞(Treg)、血小板特异性自身抗体、细胞因子的表达水平,分析其在ITP发病机制以及临床治疗中的意义。方法 73例ITP患者分为激素治疗组( n =42)、重组人粒血小板生成素(rhTPO)治疗组( n =31),并根据治疗效果分为有效组和无效组。流式细胞术检测患者治疗前后外周血CD8^+CD28^- Treg的表达,流式微球技术检测患者外周血血小板特异性自身抗体的表达。ELISA法检测患者治疗前后转化生长因子(TGF)-β1、白介素(IL)-10和干扰素(IFN)-γ表达水平。以30例健康体检者作为正常对照组。结果① 73例ITP患者治疗前CD8^+CD28^-Treg及细胞因子IL-10、TGF-β1的表达低于正常对照组,IFN-γ表达高于正常对照组( P <0.05),激素及rhTPO治疗后有效组CD8^+CD28^- Treg、IL-10、TGF-β1的表达均比治疗前显著上升,IFN-γ的表达较治疗前显著降低( P <0.05)。无效组CD8^+CD28^- Treg、IFN-γ、IL-10、TGF-β1的表达和治疗前相比均未有明显变化。②根据受试者工作特征曲线(ROC),激素组治疗前CD8^+CD28^-Treg的临界值为14.35,此时预测激素疗效的敏感性和特异性分别为66.7%和73.3%。27例有效者中小于14.35的有18例(66.7%),15例无效者中大于14.35的有11例(73.3%)。rhTPO组治疗前CD8^+CD28^-Treg的临界值为15.45,此时预测rhTPO疗效的敏感性和特异性分别为63.6%和88.9%。22例有效者中大于15.45的有14例(63.6%),9例无效者中小于15.45的有8例(88.9%)。③激素组抗血小板膜糖蛋白Ib(GPIb)抗体阳性患者18例,治疗后有效率44.4%,抗GPIb抗体阴性24例,有效率79.1%,两者比较差异有统计学意义( P <0.05)。结论 CD8^+CD28^- Treg及相关细胞因子的表达异常参与了ITP的发病,激素和rhTPO可能通过改变这种异常发挥作用。治疗前检测CD8^+CD28^-Treg有助于预测激素及rhTPO的疗效。抗GPIb抗体阳性可能是激素治疗不敏感的影响因素之一。
基金This study was supported by the National Basic Research Program of China （2012CBA01302, 2010CB945400）, the National Natural Science Foundation of China （31171398, 81271265, 81425016）, the Key Scientific and Technological Projects of Guangdong Province （2007A032100003）, the Natural Science Foundation of Guangdong Province （ S2013030013305 ）, the Key Scientific and Technological Program of Guangzhou City （201400000003-3, 201300000089, 2010U1-E00551 ） and Guangdong Department of Science ＆ Technology Translational Medicine Center grant （2011A080300002）.
文摘One important aspect of mesenchymal stromal cells （MSCs）-mediated immunomodulation is the recruitment and induction of regulatory T （Treg） cells. However, we do not yet know whether MSCs have similar effects on the other subsets of Treg cells. Herein, we studied the effects of MSCs on CD8＋CD28- Treg cells and found that the MSCs could not only increase the proportion of CD8＋CD28- T cells, but also enhance CD8＋CD28-T cells＇ ability of hampering naive CD4＋ T-cell proliferation and activation, decreasing the production of IFN-γ by activated CD4＋ T cells and inducing the apoptosis of activated CD4＋ T cells. Mechanistically, the MSCs affected the functions of the CD8＋CD28- T cells partially through moderate upregulating the expression of IL-10 and FasL. The MSCs had no distinct effect on the shift from CD8＋CD28＋ T cells to CD8＋CD28- T cells, but did increase the proportion of CD8＋CD28- T cells by reducing their rate of apoptosis. In summary, this study shows that MSCs can enhance the regulatory function of CD8＋CD28- Treg cells, shedding new light on MSCs-mediated immune regulation.
文摘CD8^(+)T cells are regulatory T cells(Tregs)that suppress both alloimmunity and autoimmunity in many animal models.This class of regulatory cells includes the CD8^(+)CD28^(-),CD8^(+)CD103^(+),CD8^(+)FoxP3^(+)and CD8^(+)CD122^(+)subsets.The mechanisms of action of these regulatory cells are not fully understood;however,the secretion of immunosuppressive cytokines,such as interleukin(IL)-4,IL-10 and transforming growth factor beta(TGF-β)as well as the direct killing of target cells via Fas L/Fas and the perforin/granzyme B pathways have been demonstrated in various models.Further studies are necessary to fully understand the mechanisms underlying the suppressive effects of Tregs and to provide experimental support for potential clinical trials.We recently observed that CD8^(+)CD122^(+)Tregs more potently suppressed allograft rejection compared to their CD4^(+)CD25^(+)counterparts,supporting the hypothesis that CD8^(+)Tregs may represent a new and promising Treg family that can be targeted to prevent allograft rejection in the clinic.In this review,we summarize the progress in the field during the past 7-10 years and discuss CD8^(+)Treg phenotypes,mechanisms of action,and their potential clinical applications;particularly in composite tissue transplants in burn and trauma patients.
文摘Despite extensive studies on CD4^＋CD25^＋ regulatory T cells （Tregs） during the past decade, the progress on their clinical translation remains stagnant. Mounting evidence suggests that naturally occurring CD8^＋CD122^＋ T cells are also Tregs with the capacity to inhibit T-cell responses and suppress autoimmunity as well as alloimmunity. In fact, they are memory-like Tregs that resemble a central memory T cell （TcM） phenotype. The mechanisms underlying their suppression are still not well understood, although they may include IL-IO production. We have recently demonstrated that programmed death-1 （PD-1） expression distinguishes between regulatory and memory CD8^＋CD122^＋ T cells and that CD8^＋CD122^＋ Tregs undergo faster homeostatic proliferation and are more potent in the suppression of allograft rejection than conventional CD4^＋CD25^＋ Tregs. These findings may open a new line of investigation for accelerating effective Treg therapies in the clinic. In this review, we summarize the significant progress in this promising field of CD8^＋CD122^＋ Treg research and discuss their phenotypes, suppressive roles in autoimmunity and alloimmunity, functional requirements, mechanisms of action and potential applications in the clinic.
基金supported by the National Natural Science Foundation of China(No.31570931 and No.31771002)the National Key Project for Research&Development of China(Grant no.2016YFA0502204).
文摘Autoreactive CD8^(+)T cells,which play an indispensable role inβcell destruction,represent an emerging target for the prevention of type 1 diabetes(T1D).Altered peptide ligands(APLs)can efficiently induce antigen-specific T cells anergy,apoptosis or shifts in the immune response.Here,we found that HLA-A*0201-restricted CD8^(+)T cell responses against a primaryβ-cell autoantigen insulin epitope InsB15–14 were present in both NOD.β2m null.HHD NOD mice and T1D patients.We generated several APL candidates for InsB15–14 by residue substitution at the p6 position.Only H6F exhibited an inhibitory effect on mInsB1_(5–14)-specific CD8^(+)T cell responses in vitro.H6F treatment significantly reduced the T1D incidence,which was accompanied by diminished autoreactive CD8^(+)T cell responses to mInsB15-14,inhibited infiltration of CD8^(+)and CD4^(+)T cells in the pancreas and reduced pro-inflammatory cytokine production in pancreatic and splenic T cells in NOD.β2m^(null).HHD mice.Mechanistically,H6F treatment significantly augmented a tiny portion of CD8^(+)CD25^(+)Foxp3^(+)T cells in the spleen and especially in the pancreas.This subset exhibited typical Treg phenotypes and required peptide-specific restimulation to exert immunosuppressive activity.Therefore,this APL H6F may be a promising candidate with potential clinical application value for antigen-specific prevention of T1D.
