目的建立重组Omicron BA.4/5-Delta株新冠疫苗体外相对效力的检测方法,并进行验证,以期为替代体内效力检测奠定基础。方法以人源单克隆抗体GH4作为包被抗体,HRP标记的CB6人源单克隆抗体作为酶标抗体的双抗体夹心ELISA法为基础,确定疫苗...目的建立重组Omicron BA.4/5-Delta株新冠疫苗体外相对效力的检测方法,并进行验证,以期为替代体内效力检测奠定基础。方法以人源单克隆抗体GH4作为包被抗体,HRP标记的CB6人源单克隆抗体作为酶标抗体的双抗体夹心ELISA法为基础,确定疫苗解吸附方法;再以该解吸附方法结合双抗体夹心ELISA法建立体外相对效力检测方法。并验证方法的线性范围、专属性、准确性、精密性、耐用性及定量限。采用建立的方法检测3批供试品重组Omicron BA.4/5-Delta株新冠疫苗的体外相对效力。结果确定解吸附方法为:将疫苗与处理液(1.25 mL 20%二乙醇胺,0.20 mL 10%Triton X-100,8.55 mL PBS)按等体积分数混合,于25℃解离30 min,解吸附率可达95%以上。疫苗参考品在1~26 ng/mL浓度范围内,与A_(450)呈良好的线性关系,线性方程为log(y)=1.447 log(x)-1.643,R^(2)为0.998;可特异性检测疫苗参考品的体外相对效力;90000、50000和20000 ng/mL浓度疫苗参比品检测结果的回收率均在80%~120%范围内;重复性及中间精密性验证相对标准偏差(relative standard deviation,RSD)均<20%;解离条件、检测体系孵育时间和显色时间发生微小变动时,检测结果不受影响;定量限为0.2。批号为J202301002、J202301003、J202301004供试品的体外相对效力分别为1.0,1.0和0.8,RSD为11%。结论建立的用于检测体外相对效力的方法具有良好的准确性、精密性、专属性和耐用性,可用于重组Omicron BA.4/5-Delta株新冠疫苗体外相对效力的检测。展开更多
The recent concurrent emergence of H5N1,H5N6,and H5N8 avian influenza viruses(AIVs)has led to significant avian mortality globally.Since 2020,frequent human-animal interactions have been documented.To gain insight int...The recent concurrent emergence of H5N1,H5N6,and H5N8 avian influenza viruses(AIVs)has led to significant avian mortality globally.Since 2020,frequent human-animal interactions have been documented.To gain insight into the novel H5 subtype AIVs(i.e.,H5N1,H5N6 and H5N8),we collected 6102 samples from various regions of China between January 2021 and September 2022,and identified 41 H5Nx strains.Comparative analyses on the evolution and biological properties of these isolates were conducted.Phylogenetic analysis revealed that the 41 H5Nx strains belonged to clade 2.3.4.4b,with 13 related to H5N1,19 to H5N6,and 9 to H5N8.Analysis based on global 2.3.4.4b viruses showed that all the viruses described in this study were likely originated from H5N8,exhibiting a heterogeneous evolutionary history between H5N1 and H5N6 during 2015–2022 worldwide.H5N1 showed a higher rate of evolution in 2021–2022 and more sites under positive selection pressure in 2015–2022.The antigenic profiles of the novel H5N1 and H5N6 exhibited notable variations.Further hemagglutination inhibition assay suggested that some A(H5N1)viruses may be antigenically distinct from the circulating H5N6 and H5N8 strains.Mammalian challenge assays demonstrated that the H5N8 virus(21GD001_H5N8)displayed the highest pathogenicity in mice,followed by the H5N1 virus(B1557_H5N1)and then the H5N6 virus(220086_H5N6),suggesting a heterogeneous virulence profile of H5 AIVs in the mammalian hosts.Based on the above results,we speculate that A(H5N1)viruses have a higher risk of emergence in the future.Collectively,these findings unveil a new landscape of different evolutionary history and biological characteristics of novel H5 AIVs in clade 2.3.4.4b,contributing to a better understanding of designing more effective strategies for the prevention and control of novel H5 AIVs.展开更多
Traditionally, the multibasic cleavage site （MBCS） of surface protein H5-hemagglutinin （HA） is converted to a monobasic one so as to weaken the virulence of recombinant H5N1 influenza viruses and to produce inacti...Traditionally, the multibasic cleavage site （MBCS） of surface protein H5-hemagglutinin （HA） is converted to a monobasic one so as to weaken the virulence of recombinant H5N1 influenza viruses and to produce inactivated and live attenuated vaccines. Whether such modification benefits new candidate vaccines has not been adequately investigated. We previously used retroviral vectors to generate wtH5N1 pseudotypes containing the wild-type HA （wtH5） from A/swine/Anhui/ca/2004 （H5N1） virus. Here, we generated mtH5N1 pseudotypes, which contained a mutant-type HA （mtH5） with a modified monobasic cleavage site. Groups of mice were subcutaneously injected with the two types of influenza pseudotypes. Compared to the group immunized with wtH5N1 pseudotypes, the inoculation of mtH5N1 pseudotypes induced significantly higher levels of HA specific IgG and IFN-y in immunized mice, and enhanced protection against the challenge of mouse-adapted avian influenza virus A/Chicken/Henardl2/2004 （H5N1）. This study suggests modification of the H5-hemagglutinin MBCS in retroviral pseudotypes enhances protection efficacy in mice and this information may be helpful for development of vaccines from mammalian cells to fight against H5N 1 influenza viruses.展开更多
The New Niobate Ba5NdTi3Nb7O30 was synthesized by solid state reaction at 1250℃ for 48h. The crystal structure and dielectric properties of Ba5NdTi3Nb7O30 were determined by X ray powder diffraction and dielectric me...The New Niobate Ba5NdTi3Nb7O30 was synthesized by solid state reaction at 1250℃ for 48h. The crystal structure and dielectric properties of Ba5NdTi3Nb7O30 were determined by X ray powder diffraction and dielectric measurements. The results show that Ba5NdTi3Nb7O30 belongs to ferroelectric phase of tetragonal tungsten bronze structure at room temperature with unit cell parameters: a=1.24424(4)nm, c=0.39476(2)nm, calculated density 5.719g·cm-3. Ba5NdTi3Nb7O30 belongs to relaxor ferroelectrics. The phase transition temperature (Tc) of Ba5NdTi3Nb7O30 from ferroelectric to paraelectric is found to shift toward higher temperature side at higher frequency, and Tc is 90℃ at 1kHz. At room temperature, the dielectric constant (εr) and dielectric loss of Ba5NdTi3Nb7O30 decrease with the increase of frequency, and Ba5NdTi3Nb7O30 ceramic have high dielectric constant 489 at 1kHz.展开更多
文摘目的建立重组Omicron BA.4/5-Delta株新冠疫苗体外相对效力的检测方法,并进行验证,以期为替代体内效力检测奠定基础。方法以人源单克隆抗体GH4作为包被抗体,HRP标记的CB6人源单克隆抗体作为酶标抗体的双抗体夹心ELISA法为基础,确定疫苗解吸附方法;再以该解吸附方法结合双抗体夹心ELISA法建立体外相对效力检测方法。并验证方法的线性范围、专属性、准确性、精密性、耐用性及定量限。采用建立的方法检测3批供试品重组Omicron BA.4/5-Delta株新冠疫苗的体外相对效力。结果确定解吸附方法为:将疫苗与处理液(1.25 mL 20%二乙醇胺,0.20 mL 10%Triton X-100,8.55 mL PBS)按等体积分数混合,于25℃解离30 min,解吸附率可达95%以上。疫苗参考品在1~26 ng/mL浓度范围内,与A_(450)呈良好的线性关系,线性方程为log(y)=1.447 log(x)-1.643,R^(2)为0.998;可特异性检测疫苗参考品的体外相对效力;90000、50000和20000 ng/mL浓度疫苗参比品检测结果的回收率均在80%~120%范围内;重复性及中间精密性验证相对标准偏差(relative standard deviation,RSD)均<20%;解离条件、检测体系孵育时间和显色时间发生微小变动时,检测结果不受影响;定量限为0.2。批号为J202301002、J202301003、J202301004供试品的体外相对效力分别为1.0,1.0和0.8,RSD为11%。结论建立的用于检测体外相对效力的方法具有良好的准确性、精密性、专属性和耐用性,可用于重组Omicron BA.4/5-Delta株新冠疫苗体外相对效力的检测。
基金supported by the Science and Technology Program of Guangdong Province(2022B1111010004,2021B1212030015)China Agriculture Research System of MOF and MARA(CARS-41)China National Animal Disease Surveillance and Epidemiological Survey Program(2021–2025)(No.202111).
文摘The recent concurrent emergence of H5N1,H5N6,and H5N8 avian influenza viruses(AIVs)has led to significant avian mortality globally.Since 2020,frequent human-animal interactions have been documented.To gain insight into the novel H5 subtype AIVs(i.e.,H5N1,H5N6 and H5N8),we collected 6102 samples from various regions of China between January 2021 and September 2022,and identified 41 H5Nx strains.Comparative analyses on the evolution and biological properties of these isolates were conducted.Phylogenetic analysis revealed that the 41 H5Nx strains belonged to clade 2.3.4.4b,with 13 related to H5N1,19 to H5N6,and 9 to H5N8.Analysis based on global 2.3.4.4b viruses showed that all the viruses described in this study were likely originated from H5N8,exhibiting a heterogeneous evolutionary history between H5N1 and H5N6 during 2015–2022 worldwide.H5N1 showed a higher rate of evolution in 2021–2022 and more sites under positive selection pressure in 2015–2022.The antigenic profiles of the novel H5N1 and H5N6 exhibited notable variations.Further hemagglutination inhibition assay suggested that some A(H5N1)viruses may be antigenically distinct from the circulating H5N6 and H5N8 strains.Mammalian challenge assays demonstrated that the H5N8 virus(21GD001_H5N8)displayed the highest pathogenicity in mice,followed by the H5N1 virus(B1557_H5N1)and then the H5N6 virus(220086_H5N6),suggesting a heterogeneous virulence profile of H5 AIVs in the mammalian hosts.Based on the above results,we speculate that A(H5N1)viruses have a higher risk of emergence in the future.Collectively,these findings unveil a new landscape of different evolutionary history and biological characteristics of novel H5 AIVs in clade 2.3.4.4b,contributing to a better understanding of designing more effective strategies for the prevention and control of novel H5 AIVs.
基金supported by the National Basic Research Program of China (973: 2012CB518904) from the Ministry of Science and Technology of Chinathe National Natural Science Foundation of China(81201298)
文摘Traditionally, the multibasic cleavage site （MBCS） of surface protein H5-hemagglutinin （HA） is converted to a monobasic one so as to weaken the virulence of recombinant H5N1 influenza viruses and to produce inactivated and live attenuated vaccines. Whether such modification benefits new candidate vaccines has not been adequately investigated. We previously used retroviral vectors to generate wtH5N1 pseudotypes containing the wild-type HA （wtH5） from A/swine/Anhui/ca/2004 （H5N1） virus. Here, we generated mtH5N1 pseudotypes, which contained a mutant-type HA （mtH5） with a modified monobasic cleavage site. Groups of mice were subcutaneously injected with the two types of influenza pseudotypes. Compared to the group immunized with wtH5N1 pseudotypes, the inoculation of mtH5N1 pseudotypes induced significantly higher levels of HA specific IgG and IFN-y in immunized mice, and enhanced protection against the challenge of mouse-adapted avian influenza virus A/Chicken/Henardl2/2004 （H5N1）. This study suggests modification of the H5-hemagglutinin MBCS in retroviral pseudotypes enhances protection efficacy in mice and this information may be helpful for development of vaccines from mammalian cells to fight against H5N 1 influenza viruses.
文摘The New Niobate Ba5NdTi3Nb7O30 was synthesized by solid state reaction at 1250℃ for 48h. The crystal structure and dielectric properties of Ba5NdTi3Nb7O30 were determined by X ray powder diffraction and dielectric measurements. The results show that Ba5NdTi3Nb7O30 belongs to ferroelectric phase of tetragonal tungsten bronze structure at room temperature with unit cell parameters: a=1.24424(4)nm, c=0.39476(2)nm, calculated density 5.719g·cm-3. Ba5NdTi3Nb7O30 belongs to relaxor ferroelectrics. The phase transition temperature (Tc) of Ba5NdTi3Nb7O30 from ferroelectric to paraelectric is found to shift toward higher temperature side at higher frequency, and Tc is 90℃ at 1kHz. At room temperature, the dielectric constant (εr) and dielectric loss of Ba5NdTi3Nb7O30 decrease with the increase of frequency, and Ba5NdTi3Nb7O30 ceramic have high dielectric constant 489 at 1kHz.
