作　　者： ; ; ; ; ;

机构地区： 南方医科大学

出　　处： 《免疫学杂志》 2006年第6期698-701,共4页

摘　　要： 目的评价重组禽流感疫苗株rH5N3的生物学特性和免疫效果。方法将rH5N3注射SPF鸡胚和SPF鸡,观察其致病性;rH5N3及其亲本毒株A/Goose/HLJ/QFY/04分别在MDCK细胞单层和SPF鸡胚中增值,研究其生长特性;rH5N3在SPF鸡胚中连续传代,测定第10代rH5N3的核酸序列,评价其遗传稳定性;制备油包水型灭活rH5N3疫苗接种SPF鸡,免疫后不同时间采血测HI抗体滴度;rH5N3灭活疫苗接种SPF鸡,免疫后3周采血测定HI抗体滴度,同时进行H5N1亚型强毒株攻击,观察其保护作用。结果rH5N3疫苗株对鸡和鸡胚均无致病性;其在鸡胚尿囊液和细胞培养上清液的HA效价极大提高,分别为1:2048和1:512;第10代rH5N3的核酸序列与其亲本毒株相同;灭活rH5N3疫苗免疫鸡后2周即可诱导产生高效价HI抗体,且免疫后18周依然保持较高水平;该疫苗对强毒株包括国内早期分离的A/Goose/Guangdong/1/96和近期分离的A/Goose/HLJ/QFY/04都能产生完全的保护作用,免疫鸡攻毒后不发病、不排毒、不死亡。结论rH5N3疫苗株具有安全、高产、稳定等特点,且具良好的免疫原性,免疫动物完全能够抵抗强毒株的致死性攻击。该疫苗株的成功研制为H5N1亚型高致病性禽流感的防控提供了新的技术保障。 Objective To evaluate the biological characteristics and the immune efficacy of the recombinant avian influenza vaccine strain rH5N3. Methods The pathogenicity of rH5N3 in SPF chicken and embryonated eggs was analyzed. The growth characteristics of rH5N3 and its parent H5N1 vires strain A/Goose/HLJ/QFY/04 were compared in MDCK cells and SPF chicken embryonated eggs. The genetic stability of rH5N3 in chicken embryonated eggs was evaluated by sequential passage experiment and its nucleic acid was sequenced. SPF chickens were vaccinated with formalin-inactivated oil-emulsion rH5N3 vaccine, and then the sera of the chickens was collected at different times and detected for hemagglutination inhibition （HI） antibody titer. Three weeks after vaccination with the inactivated rH5N3 vaccine, the SPF chickens were detected for the titer of HI antibody in sere and attacked with the strains of highly pathogenic avian influenza A vires of H5N1 subtype （A/ Goose/Guangdong/1/96 and A/Goose/HLJ/QFY/04）. Results The chickens＇ embryos infection and chickerls challenge tests demonstrated that rH5N3 was non-virulent. The allantoic fluids of rH5N3-infected eggs and the supernatants of rH5N3-infeeted MDCK cells contain high titer viruses （1：512 and 1：2 048, respectively）, which were eight times that of the parental virus strain A/Geose/HLJ/QFY/04. After ten sequential passages in chicken embryonated eggs, the nucleic acid sequence of rH5N3 didn＇ t change. The rH5N3 vaccine could induce HI antibodies in chickens in 2 weeks post-vaccination and the maximum geometric mean HI titer were observed on 4-5 weeks post-vaccination and were kept in the eighteen weeks. The rH5N3-vaccinated chickens were fully protected against the lethal challenge of the H5N1 virulent viruses （ both A/ GonseJGuangdong/1/96 and A/Geose/HLJ/QFY/04）. Condusion The vaccine strain rH5N3 characterized by low-virulence, high yield, good genetic stability, and favorable immunogenicity, can protect poultry from fatal attack of virulent viruses. The

关 键 词： 重组禽流感疫苗株 生物学特性 体液免疫 保护作用

领　　域： [农业科学] [农业科学] [农业科学]