H9N2 avian influenza virus(AIV)poses a persistent threat as inactivated vaccines(InV)often fail to prevent viral shedding.To address this,we developed a recombinant turkey herpesvirus(HVT-BNT)expressing conserved B an...H9N2 avian influenza virus(AIV)poses a persistent threat as inactivated vaccines(InV)often fail to prevent viral shedding.To address this,we developed a recombinant turkey herpesvirus(HVT-BNT)expressing conserved B and T cell epitopes from H9N2 AIV to enhance both humoral and cellular immunity.HVT-BNT exhibited genetic stability over 15 serial passages and growth kinetics comparable to the parental strain in vitro.We evaluated immunization strategies of HVT-BNT combined with InV in 1-day-old chicks and 18-day-old embryos via subcutaneous(HVT-BNT+InV)or in ovo(HVT-BNT-ovo+InV)routes,respectively.Compared to InV alone,HVT-BNT+InV elicited significantly higher HI and neutralizing antibody titers,elevated IgG and IgM levels,and increased proportions of CD8+T cells.Similarly,the HVT-BNT-ovo+InV group exhibited a trend of higher values in these indicators.Notably,while the InV group displayed no significant differences in key immune cytokines compared to the control group,the combined immunization groups exhibited significant upregulation of IFN-α,IFN-β,IFN-γ,IL-2,IL-5,IL-6,IL-10,and IL-13.Furthermore,ELISPOT assays confirmed enhanced IFN-γsecretion in response to conserved AIV peptides(NP380-393,NP455-463,and NS198-106)in the combined immunization groups.Following heterologous H9N2 AIV challenge,oropharyngeal positivity rates in the combined immunization groups were lower than those in the InV group at 5 DPI.Similarly,cloacal positivity rates were more reduced in the combined groups compared to the InV group at 3 and 5 DPI.By 7 DPI,viral shedding was completely cleared in both combined immunization groups,whereas the InV group continued to shed virus via the oropharyngeal route.These findings demonstrate that the HVT-BNT-based vaccination strategy effectively enhances both humoral and cellular immune responses,providing superior early protection.While the in ovo strategy provides a viable hatchery intervention,the subcutaneous route exhibits the superior immune activation and protection compared with conventional InV alone.展开更多
The H9N2 subtype avian influenza virus(AIV)hemagglutinin(HA)protein is a major immunogen in which HA1 is a genetic variant and HA2 is relatively conserved.Identifying broad-spectrum antigen epitopes targeting HA1 is c...The H9N2 subtype avian influenza virus(AIV)hemagglutinin(HA)protein is a major immunogen in which HA1 is a genetic variant and HA2 is relatively conserved.Identifying broad-spectrum antigen epitopes targeting HA1 is crucial for vaccine design and detection.Based on the phylogenetic and serological analyses,we identified 2 antigenic groups and 3 representative viruses:A/chicken/Jiangsu/JY040218C/2019,A/pigeon/Jiangsu/JY020616/2019,and A/chicken/Jiangsu/WX090312/2018.An overlapping peptide library was synthesized using HA1 amino acid sequences of the viruses as templates.Through peptide scanning of the sera against different strains of H9N2 subtype AIV,we identified peptides from 4 regions(H9-2/3,H9-20/21,H9-26,and H9-29/30/31)that demonstrated broad-spectrum reactivity.Immunological assay results demonstrated that H9-21(219RIFKPLIGPRPLVNGLMGRI239),H9-26(269SGESHGRILKTDLKMGSCTV289),and H9-30(309YAFGNCPKYI GVKSLKLAVG329)effectively induced antibody generation and conferred partial protective efficacy against the parent virus JY040218C.The results of lymphocyte proliferation and ELISpot assays indicated that peptides H9-15(159MRWLTQKNNAYPTQDAQYTN179),H9-22(229PLVNGLMGRINYYWSVLKP G249),and H9-23(239NYYWSVLKPGQTLRIKSDGN259)could effectively stimulate the expression of interferon-gamma in peripheral blood lymphocytes of chickens immunized against different strains of H9N2 AIV.Collectively,5 novel cell epitopes H9-15,H9-22,H9-23,H9-26,and H9-30,including the best B cell epitope H9-26 and the best T cells epitope H9-22,were identified that could be targeted for vaccine design or detection approaches against H9N2 AIVs.展开更多
为确定H9N2猪流感病毒(H9N2-SIV)通过瞬时受体电位通道M2(TRPM2)介导肺微血管上皮细胞(PMVEC)铁死亡的分子机制,使用H9N2-SIV接种PMVEC,构建TRPM2-siRNA质粒并转染细胞。用透射电镜观察细胞超微结构,用荧光探针法检测活性氧(ROS)、Ca^(...为确定H9N2猪流感病毒(H9N2-SIV)通过瞬时受体电位通道M2(TRPM2)介导肺微血管上皮细胞(PMVEC)铁死亡的分子机制,使用H9N2-SIV接种PMVEC,构建TRPM2-siRNA质粒并转染细胞。用透射电镜观察细胞超微结构,用荧光探针法检测活性氧(ROS)、Ca2+和Fe2+;用生化试剂盒检测丙二醛(MDA)和谷胱甘肽(GSH)含量,并通过荧光定量PCR和Western-blot检测葡萄糖调节蛋白78(GRP78)、TRPM2、蛋白激酶R样内质网激酶(PERK)、活化转录因子4(ATF4)、阳离子转运调控样蛋白1(CHAC1)、谷胱甘肽过氧化物酶4(GPX4)的m RNA和蛋白表达水平。结果显示,H9N2-SIV感染可诱导细胞铁死亡,敲低TRPM2可以减少细胞内ROS水平,降低Ca2+、Fe2+及MDA含量,GSH水平明显增加;此外,GRP78、PERK、ATF4、CHAC1 m RNA和蛋白表达水平下调,GPX4的m RNA和蛋白表达水平上调。结果表明,H9N2-SIV感染可诱导细胞铁死亡,其可通过激活TRPM2使Ca2+内流增多,进而激活PERK/ATF4/CHAC1信号通路,加速GSH耗竭,抑制GPX4的活性,促进细胞铁死亡。展开更多
基金supported by grants from the National Natural Science Foundation of China(32473060 and 32461120064)(to MD and ML)Talent Program under the Wens Research Center of South China Agricultural University(WS-2025-WSCX-JS-000133)(to MD)+4 种基金the National Natural Science Foundation of Guangdong Province(2024A1515013151)(to MD)Guangzhou Basic and Applied Basic Research Project(2025A04J5445 to MD)Laboratory of Lingnan Modern Agriculture Project(NT2025005 to MD)Young Scholars of Yangtze River Scholar Professor Program(2024,Manman Dai)Young Pearl River Scholar of“Guangdong Special Support Plan”(2024,Manman Dai).
摘要H9N2 avian influenza virus(AIV)poses a persistent threat as inactivated vaccines(InV)often fail to prevent viral shedding.To address this,we developed a recombinant turkey herpesvirus(HVT-BNT)expressing conserved B and T cell epitopes from H9N2 AIV to enhance both humoral and cellular immunity.HVT-BNT exhibited genetic stability over 15 serial passages and growth kinetics comparable to the parental strain in vitro.We evaluated immunization strategies of HVT-BNT combined with InV in 1-day-old chicks and 18-day-old embryos via subcutaneous(HVT-BNT+InV)or in ovo(HVT-BNT-ovo+InV)routes,respectively.Compared to InV alone,HVT-BNT+InV elicited significantly higher HI and neutralizing antibody titers,elevated IgG and IgM levels,and increased proportions of CD8+T cells.Similarly,the HVT-BNT-ovo+InV group exhibited a trend of higher values in these indicators.Notably,while the InV group displayed no significant differences in key immune cytokines compared to the control group,the combined immunization groups exhibited significant upregulation of IFN-α,IFN-β,IFN-γ,IL-2,IL-5,IL-6,IL-10,and IL-13.Furthermore,ELISPOT assays confirmed enhanced IFN-γsecretion in response to conserved AIV peptides(NP380-393,NP455-463,and NS198-106)in the combined immunization groups.Following heterologous H9N2 AIV challenge,oropharyngeal positivity rates in the combined immunization groups were lower than those in the InV group at 5 DPI.Similarly,cloacal positivity rates were more reduced in the combined groups compared to the InV group at 3 and 5 DPI.By 7 DPI,viral shedding was completely cleared in both combined immunization groups,whereas the InV group continued to shed virus via the oropharyngeal route.These findings demonstrate that the HVT-BNT-based vaccination strategy effectively enhances both humoral and cellular immune responses,providing superior early protection.While the in ovo strategy provides a viable hatchery intervention,the subcutaneous route exhibits the superior immune activation and protection compared with conventional InV alone.
基金supported by the National Key Research and Development Program of China(2021YFD1800202)the National Natural Science Foundation of China(3237042 and 32172942)+3 种基金the“Jie Bang Gua Shuai”Project at Yangzhou University,China(YZUXK202316)the Agricultural Science and Technology Independent Innovation Fund of Jiangsu Province,China(SCX[22]3547)the Outstanding Technological Innovation Team of College and University at Jiangsu Province,China([2021]NO.1)a project funded by the Priority Academic Program Development of Jiangsu Higher Education,China(PAPD)。
摘要The H9N2 subtype avian influenza virus(AIV)hemagglutinin(HA)protein is a major immunogen in which HA1 is a genetic variant and HA2 is relatively conserved.Identifying broad-spectrum antigen epitopes targeting HA1 is crucial for vaccine design and detection.Based on the phylogenetic and serological analyses,we identified 2 antigenic groups and 3 representative viruses:A/chicken/Jiangsu/JY040218C/2019,A/pigeon/Jiangsu/JY020616/2019,and A/chicken/Jiangsu/WX090312/2018.An overlapping peptide library was synthesized using HA1 amino acid sequences of the viruses as templates.Through peptide scanning of the sera against different strains of H9N2 subtype AIV,we identified peptides from 4 regions(H9-2/3,H9-20/21,H9-26,and H9-29/30/31)that demonstrated broad-spectrum reactivity.Immunological assay results demonstrated that H9-21(219RIFKPLIGPRPLVNGLMGRI239),H9-26(269SGESHGRILKTDLKMGSCTV289),and H9-30(309YAFGNCPKYI GVKSLKLAVG329)effectively induced antibody generation and conferred partial protective efficacy against the parent virus JY040218C.The results of lymphocyte proliferation and ELISpot assays indicated that peptides H9-15(159MRWLTQKNNAYPTQDAQYTN179),H9-22(229PLVNGLMGRINYYWSVLKP G249),and H9-23(239NYYWSVLKPGQTLRIKSDGN259)could effectively stimulate the expression of interferon-gamma in peripheral blood lymphocytes of chickens immunized against different strains of H9N2 AIV.Collectively,5 novel cell epitopes H9-15,H9-22,H9-23,H9-26,and H9-30,including the best B cell epitope H9-26 and the best T cells epitope H9-22,were identified that could be targeted for vaccine design or detection approaches against H9N2 AIVs.
摘要为确定H9N2猪流感病毒(H9N2-SIV)通过瞬时受体电位通道M2(TRPM2)介导肺微血管上皮细胞(PMVEC)铁死亡的分子机制,使用H9N2-SIV接种PMVEC,构建TRPM2-siRNA质粒并转染细胞。用透射电镜观察细胞超微结构,用荧光探针法检测活性氧(ROS)、Ca2+和Fe2+;用生化试剂盒检测丙二醛(MDA)和谷胱甘肽(GSH)含量,并通过荧光定量PCR和Western-blot检测葡萄糖调节蛋白78(GRP78)、TRPM2、蛋白激酶R样内质网激酶(PERK)、活化转录因子4(ATF4)、阳离子转运调控样蛋白1(CHAC1)、谷胱甘肽过氧化物酶4(GPX4)的m RNA和蛋白表达水平。结果显示,H9N2-SIV感染可诱导细胞铁死亡,敲低TRPM2可以减少细胞内ROS水平,降低Ca2+、Fe2+及MDA含量,GSH水平明显增加;此外,GRP78、PERK、ATF4、CHAC1 m RNA和蛋白表达水平下调,GPX4的m RNA和蛋白表达水平上调。结果表明,H9N2-SIV感染可诱导细胞铁死亡,其可通过激活TRPM2使Ca2+内流增多,进而激活PERK/ATF4/CHAC1信号通路,加速GSH耗竭,抑制GPX4的活性,促进细胞铁死亡。
摘要目的 探讨磷酸酶和张力蛋白同源物(PTEN)对H9c2细胞氧糖剥夺/复氧(OGD/R)损伤的影响及潜在机制。方法 取正常H9c2细胞构建OGD/R模型细胞,分别将正常H9c2细胞或OGD/R模型细胞分为空白组(不作任何处理)、阴性对照(NC)组、si-PTEN组(加入特异性小干扰RNA)、PTEN-过表达(OE)组。采用qRT-PCR法检测PTEN m RNA表达水平,采用蛋白质印迹法检测PTEN及蛋白激酶B(AKT)/细胞外信号调节激酶(ERK)信号通路相关蛋白表达水平,采用细胞计数试剂盒-8检测细胞相对活性,采用流式细胞术检测细胞凋亡率和细胞周期。结果 在正常H9c2细胞中,si-PTEN组PTEN m RNA及蛋白表达水平均明显低于空白组和NC组(均P0.05),细胞周期蛋白依赖性激酶抑制剂1A(p21)蛋白表达水平比较差异有统计学意义(P<0.001);在OGD/R模型细胞中,si-PTEN组p-AKT/AKT、p-ERK/ERK、cyclinD1蛋白表达水平均高于空白组(均P<0.05),p21蛋白表达水平低于空白组(P<0.05)。结论 H9c2细胞敲低PTEN表达可通过AKT/ERK信号通路减轻OGD/R损伤,可能是通过影响细胞凋亡和细胞周期实现的。