Rabies is a zoonotic disease that still causes 59,000 human deaths each year,and rabies vaccine is the most effective way to control the disease.Our previous studies suggested that the maturation of DC plays an import...Rabies is a zoonotic disease that still causes 59,000 human deaths each year,and rabies vaccine is the most effective way to control the disease.Our previous studies suggested that the maturation of DC plays an important role in enhancing the immunogenicity of rabies vaccine.Flt3L has been reported to own the ability to accelerate the DC maturation,therefore,in this study,a recombinant rabies virus expressing mouse Flt3L,designated as LBNSE-Flt3L,was constructed,and its immunogenicity was characterized.It was found that LBNSE-FU3L could enhance the maturation of DC both in vitro and in vivo,and significantly more TFH cells and Germinal Center B(GC B)cells were generated in mice immunized with LBNSE-FU3L than those immunized with the parent virus LBNSE.Consequently,expressing of Flt3L could elevate the level of virus-neutralizing antibodies(VNA)in immunized mice which provides a better protection from a lethal rabies virus challenge.Taken together,our study extends the potential of Flt3L as a good adjuvant to develop novel rabies vaccine by enhancing the VNA production through activating the DC—Tfh^GC B axis in immunized mice.展开更多
Dendritic cells （DCs） are immune cells specialized to capture, process and present antigen to T cells in order to initiate an appropriate adaptive immune response. The study of mouse DC has revealed a heterogeneous ...Dendritic cells （DCs） are immune cells specialized to capture, process and present antigen to T cells in order to initiate an appropriate adaptive immune response. The study of mouse DC has revealed a heterogeneous population of cells that differ in their development, surface phenotype and function. The study of human blood and spleen has shown the presence of two subsets of conventional DC including the CDlb/c＋ and CD141＋CLEC9A＋ conventional DC （cDC） and a plasmacytoid DC （pDC） that is CD304＋CD123＋. Studies on these subpopulations have revealed phenotypic and functional differences that are similar to those described in the mouse. In this study, the three DC subsets have been generated in vitrofrom human CD34＋ precursors in the presence of fins-like tyrosine kinase 3 ligand （FIt3L） and thrombopoietin （TPO）. The DC subsets so generated, including the CDlb/c＋ and CLEC9A＋ cDCs and CD123 ＋ pDCs, were largely similar to their blood and spleen counterparts with respect to surface phenotype, toll-like receptor and transcription factor expression, capacity to stimulate T cells, cytokine secretion and cross-presentation of antigens. This system may be utilized to study aspects of DC development and function not possible in vivo.展开更多
Background Dendritic ceils （DCs） are the most important professional antigen presenting cells that play a key role in initiating adaptive immune responses. The depletion and dysfunction of DCs contribute to the deve...Background Dendritic ceils （DCs） are the most important professional antigen presenting cells that play a key role in initiating adaptive immune responses. The depletion and dysfunction of DCs contribute to the development of immunodeficiency or immunoparalysis in some lung diseases. In the present study, we investigated the effects of Fms-like tyrosine kinase-3 ligand （FIt3L） administration in vivo on lung DCs expansion to provide an experimental basis of FIt3L used as a potential therapeutic agent for the related lung disorders. Methods Balb/c mice were randomly divided into FIt3L group （n=10） and control group （n=10）. Each mouse in the FIt3L group received subcutaneous administration of FIt3L at a dose of 10 pg once daily for nine consecutive days. Lung histology was observed, and CD11c and CD205 were immunologically labeled in lung tissue sections. Low-density lung cells were separated by density gradient centrifugation, and then subsets and MHC-II/I-Ad expression of DCs were analyzed by flow cytometry. Results In the FIt3L group the number and density of DC-like cells were markedly increased compared with the control group, mainly distributed in the alveolar septa. Immunological labeling in situ found that there were significantly higher numbers of CD11c＋ and CD205＋ DCs in lung mesenchymal tissue （P 〈0.05）, where they formed a denser reticular formation. Flow cytometry analysis demonstrated that the proportions of myeloid CD11c＋CD11b＋ DCs and plasmacytoid CD11c＋CD45R/B220＋ DCs in the low-density lung cells in the FIt3L group were significantly higher compared with the control group; showing 3.17- and 3.3-fold increase respectively （P 〈0.05）. The proportion of CD11c＋ DCs expressing MHC-II/I-Ad＋ was significantly increased, with a 2.7-fold increase as compared with the control group （P 〈0.05）. Conclusions FIt3L administration in vivo induces lung DCs expansion, favoring myeloid and plasmacytoid DC subsets, which are phenotypically more mature. FIt3L may be useful in the therapy to augment immune function of the lung.展开更多
基金supported by the National Program on Key Research Project of China (2016YFD0500400 and 2017YFD0501701)the National Natural Science Foundation of China (31872494, 31402176, 31372419, and 31522057)+2 种基金the Fundamental Research Funds for the Central Universities (No. 2662016QD036 to MZ)the Ministry of Science and Technology of China (863 program, No. 2011AA10A212)the Ministry of Agriculture of China (Special Fund for Agro-scientific Research in the Public Interest, No. 201303042 to ZFF)
文摘Rabies is a zoonotic disease that still causes 59,000 human deaths each year,and rabies vaccine is the most effective way to control the disease.Our previous studies suggested that the maturation of DC plays an important role in enhancing the immunogenicity of rabies vaccine.Flt3L has been reported to own the ability to accelerate the DC maturation,therefore,in this study,a recombinant rabies virus expressing mouse Flt3L,designated as LBNSE-Flt3L,was constructed,and its immunogenicity was characterized.It was found that LBNSE-FU3L could enhance the maturation of DC both in vitro and in vivo,and significantly more TFH cells and Germinal Center B(GC B)cells were generated in mice immunized with LBNSE-FU3L than those immunized with the parent virus LBNSE.Consequently,expressing of Flt3L could elevate the level of virus-neutralizing antibodies(VNA)in immunized mice which provides a better protection from a lethal rabies virus challenge.Taken together,our study extends the potential of Flt3L as a good adjuvant to develop novel rabies vaccine by enhancing the VNA production through activating the DC—Tfh^GC B axis in immunized mice.
文摘Dendritic cells （DCs） are immune cells specialized to capture, process and present antigen to T cells in order to initiate an appropriate adaptive immune response. The study of mouse DC has revealed a heterogeneous population of cells that differ in their development, surface phenotype and function. The study of human blood and spleen has shown the presence of two subsets of conventional DC including the CDlb/c＋ and CD141＋CLEC9A＋ conventional DC （cDC） and a plasmacytoid DC （pDC） that is CD304＋CD123＋. Studies on these subpopulations have revealed phenotypic and functional differences that are similar to those described in the mouse. In this study, the three DC subsets have been generated in vitrofrom human CD34＋ precursors in the presence of fins-like tyrosine kinase 3 ligand （FIt3L） and thrombopoietin （TPO）. The DC subsets so generated, including the CDlb/c＋ and CLEC9A＋ cDCs and CD123 ＋ pDCs, were largely similar to their blood and spleen counterparts with respect to surface phenotype, toll-like receptor and transcription factor expression, capacity to stimulate T cells, cytokine secretion and cross-presentation of antigens. This system may be utilized to study aspects of DC development and function not possible in vivo.
基金This research was supported by the grant from the National Natural Science Foundation of China （No. 81000848）.
文摘Background Dendritic ceils （DCs） are the most important professional antigen presenting cells that play a key role in initiating adaptive immune responses. The depletion and dysfunction of DCs contribute to the development of immunodeficiency or immunoparalysis in some lung diseases. In the present study, we investigated the effects of Fms-like tyrosine kinase-3 ligand （FIt3L） administration in vivo on lung DCs expansion to provide an experimental basis of FIt3L used as a potential therapeutic agent for the related lung disorders. Methods Balb/c mice were randomly divided into FIt3L group （n=10） and control group （n=10）. Each mouse in the FIt3L group received subcutaneous administration of FIt3L at a dose of 10 pg once daily for nine consecutive days. Lung histology was observed, and CD11c and CD205 were immunologically labeled in lung tissue sections. Low-density lung cells were separated by density gradient centrifugation, and then subsets and MHC-II/I-Ad expression of DCs were analyzed by flow cytometry. Results In the FIt3L group the number and density of DC-like cells were markedly increased compared with the control group, mainly distributed in the alveolar septa. Immunological labeling in situ found that there were significantly higher numbers of CD11c＋ and CD205＋ DCs in lung mesenchymal tissue （P 〈0.05）, where they formed a denser reticular formation. Flow cytometry analysis demonstrated that the proportions of myeloid CD11c＋CD11b＋ DCs and plasmacytoid CD11c＋CD45R/B220＋ DCs in the low-density lung cells in the FIt3L group were significantly higher compared with the control group; showing 3.17- and 3.3-fold increase respectively （P 〈0.05）. The proportion of CD11c＋ DCs expressing MHC-II/I-Ad＋ was significantly increased, with a 2.7-fold increase as compared with the control group （P 〈0.05）. Conclusions FIt3L administration in vivo induces lung DCs expansion, favoring myeloid and plasmacytoid DC subsets, which are phenotypically more mature. FIt3L may be useful in the therapy to augment immune function of the lung.
