Perforin is a pore-forming protein engaged mainly in mediating target T cell death and is employed by cytotoxic T lymphocytes （CTLs） and natural killer cells. However, whether it also plays a role in conventional C...Perforin is a pore-forming protein engaged mainly in mediating target T cell death and is employed by cytotoxic T lymphocytes （CTLs） and natural killer cells. However, whether it also plays a role in conventional CD4^＋ T cell function remains unclear. Here we report that in perforin-deficient （PKO） mice, CD4^＋ T cells are hyperproliferative in response to T cell receptor （TCR） stimulation. This feature of hyperproliferation is accompanied by the enhancement both in cell division and in IL-2 secretion. It seems that the perforin deficiency does not influence T cell development in thymus spleen and lymph node. In vivo, perforin deficiency results in increased antigen-specific T cell proliferation and antibody production. Furthermore, PKO mice are more susceptible to experimental autoimmune uveitis. To address the molecular mechanism, we found that after TCR stimulation, CD4^＋ T cells from PKO mice display an increased intracellular calcium flux and subsequently enhance activation of transcription factor NFAT1. Our results indicate that perforin plays a negative role in regulating CD4^＋ T cell activation and immune response by affecting TCR-dependent Ca^2＋ signaling.展开更多
T细胞需要两组信号刺激才能充分活化,一组由MHC抗原肽和TCR结合后提供;另一组由抗原递呈细胞提供的协同刺激信号。T细胞上的CD28/细胞毒性T淋巴细胞相关抗原4[(Cytotoxic T lym-phocyte-associatedantigen 4,CTLA-4(CD152)]与抗原递呈...T细胞需要两组信号刺激才能充分活化,一组由MHC抗原肽和TCR结合后提供;另一组由抗原递呈细胞提供的协同刺激信号。T细胞上的CD28/细胞毒性T淋巴细胞相关抗原4[(Cytotoxic T lym-phocyte-associatedantigen 4,CTLA-4(CD152)]与抗原递呈细胞上的B7(B7-1,B7-2)是目前发现的最为重要的协同刺激分子,它们在自身免疫病患者T细胞及抗原递呈细胞上有异常表达,且参与致病过程。展开更多
The role of anti-tumor immune responses in oncolytic adenoviral therapy has not been well studied due to lack of efficacious tu- mor model in immunocompetent mice.Here,we evaluated the contributions of immune componen...The role of anti-tumor immune responses in oncolytic adenoviral therapy has not been well studied due to lack of efficacious tu- mor model in immunocompetent mice.Here,we evaluated the contributions of immune components to the therapeutic effects of oncolytic adenoviruse in an immunocompetent murine tumor model permissive for infection and replication of adenovirus.We found that CD8+T cells were critical mediator for antitumor efficacy by oncolytic adenovirus.Intratumoral viral therapy induced intensive infiltration of CD8+T cells in tumor,increased tumor-specific IFN-?(interferon-?)production and CTL(cytotoxic T lymphocyte)activity of lymphocytes,and generated a long-term tumor-specific immune memory.Boosting CD8+T cell responses by agonistic anti-4-1BB(cluster differentiation 137,CD137)antibody showed synergistic anticancer effects with oncolytic viro- therapy.Our results provide insight into antitumor mechanisms of oncolytic adenovirus in addition to their direct oncolytic effect.展开更多
基金Acknowledgments We thank Drs Hua Gu （Columbia University, USA）, Weiguo Zhang （Duke University Medical Center, USA）, and Youhai H Chen （University of Pennsylvania, USA） for reviewing the manuscript and for suggestions, and Dr Ilia Voskoboinik （Peter MacCallum Cancer Centre, Australia） for providing the mouse perforin cDNA in pKS（＋） Bluescript. Ragl^-/- mice were gifts from Xiaolong Liu （Shanghai Institutes for Biological Sciences, China）. This work was supported by grants from the National Natural Science Foundation of China （30325018, 30530700, 30623003, and 30421005） and CAS project （KSCX1-YW-R-43）, grants from the National Key Project 973 （2006CB504300 and 2007CB512404）, grants from the Technology Commission of Shanghai Municipality （04DZ14902, 04DZ19108, 06DZ22032, 04DZ19112, 07XD14033, and 07DZ22916）, 863 key project （2006AA02A247）, and a grant from the E-institutes of Shanghai Universities Immunology Division.
文摘Perforin is a pore-forming protein engaged mainly in mediating target T cell death and is employed by cytotoxic T lymphocytes （CTLs） and natural killer cells. However, whether it also plays a role in conventional CD4^＋ T cell function remains unclear. Here we report that in perforin-deficient （PKO） mice, CD4^＋ T cells are hyperproliferative in response to T cell receptor （TCR） stimulation. This feature of hyperproliferation is accompanied by the enhancement both in cell division and in IL-2 secretion. It seems that the perforin deficiency does not influence T cell development in thymus spleen and lymph node. In vivo, perforin deficiency results in increased antigen-specific T cell proliferation and antibody production. Furthermore, PKO mice are more susceptible to experimental autoimmune uveitis. To address the molecular mechanism, we found that after TCR stimulation, CD4^＋ T cells from PKO mice display an increased intracellular calcium flux and subsequently enhance activation of transcription factor NFAT1. Our results indicate that perforin plays a negative role in regulating CD4^＋ T cell activation and immune response by affecting TCR-dependent Ca^2＋ signaling.
文摘T细胞需要两组信号刺激才能充分活化,一组由MHC抗原肽和TCR结合后提供;另一组由抗原递呈细胞提供的协同刺激信号。T细胞上的CD28/细胞毒性T淋巴细胞相关抗原4[(Cytotoxic T lym-phocyte-associatedantigen 4,CTLA-4(CD152)]与抗原递呈细胞上的B7(B7-1,B7-2)是目前发现的最为重要的协同刺激分子,它们在自身免疫病患者T细胞及抗原递呈细胞上有异常表达,且参与致病过程。
基金supported by the National Natural Science Foundation of China(30771968 and 91029719)
文摘The role of anti-tumor immune responses in oncolytic adenoviral therapy has not been well studied due to lack of efficacious tu- mor model in immunocompetent mice.Here,we evaluated the contributions of immune components to the therapeutic effects of oncolytic adenoviruse in an immunocompetent murine tumor model permissive for infection and replication of adenovirus.We found that CD8+T cells were critical mediator for antitumor efficacy by oncolytic adenovirus.Intratumoral viral therapy induced intensive infiltration of CD8+T cells in tumor,increased tumor-specific IFN-?(interferon-?)production and CTL(cytotoxic T lymphocyte)activity of lymphocytes,and generated a long-term tumor-specific immune memory.Boosting CD8+T cell responses by agonistic anti-4-1BB(cluster differentiation 137,CD137)antibody showed synergistic anticancer effects with oncolytic viro- therapy.Our results provide insight into antitumor mechanisms of oncolytic adenovirus in addition to their direct oncolytic effect.
