以小鼠为模型评价重组伪狂犬病病毒rPRV-HA的免疫效力

以小鼠为动物模型，对此前构建的表达H3N2亚型猪流感病毒（SIV）血凝素（HA）基因的重组伪狂犬病病毒（rPRV-HA）进行了免疫效力评价。按每只10^5.0 TCID50 rPRV-HA的剂量通过滴鼻接种8周龄雌性BALB／c小鼠（n=60），同时设Bartha-K61免疫对照组（n=60）、非免疫攻毒对照组（n=20）和非免疫不攻毒对照组（n=10）。于免疫后不同时间分别从rPRV-HA免疫组和Bartha—K61免疫对照组随机剖杀一定数量的小鼠，其余小鼠于免疫后第28天用10^5.0 TCID50同亚型SIV毒株A／Swine／Heilongjiang／74／2000（H3N2）进行强毒攻击。攻毒后第4、7、14天分别剖杀小鼠，进行间接免疫荧光、病毒分离、血清学和病理组织学检测。结果表明，重组病毒主要分布于肺脏；免疫后14d起，从rPRV—HA免疫组及Bartha—K61免疫对照组均可检测到针对PRV的荧光抗体；从rPRV—HA免疫组可以检测到针对SIV的荧光抗体和血凝抑制抗体，而各对照组均呈阴性。攻毒后从rPRV—HA免疫组小鼠未分离到攻击病毒，血凝抑制抗体显著升高，病理变化显著轻于对照组，表明rPRV—HA免疫小鼠可以抵抗同亚型SIV的攻击，可以作为rPRV—HA免疫效力评价模型。

Efficacy Evaluation of a Recombinant Pseudorabies Virus Expressing the Hemagglutinin Gene from H3N2 Subtype Swine Influenza Virus as Vaccine in a Mouse Model

A recombinant pseudorabies virus(PRV)(rPRV-HA) expressing the hemagglutinin(HA) gene from H3N2 subtype swine influenza virus(SIV) was evaluated in a mouse model.A total of 150 8-week-old female BALB/c mice were used in this study.The mice were each inoculated intranasally with 10~(5.0) TCID_(50) of rPRV-HA(rPRV-HA group,n=60) or attenuated vaccine Bartha-K61(Bartha-K61 group,n=60),and another two unimmunized groups served as challenged group(n=20) or unchallenged group(n=10).Some mice in rPRV-HA and Bartha-K61 groups were sacrificed for antigen detection and virus isolation at different days post-immunization(DPI),and the others were each challenged with 10~(5.0) TCID_(50) of the same subtype SIV 28 DPI.Recombinant virus could be detected in the lung of rPRV-HA-immunized mice.Antibody responses to PRV were detected by indirect immunofluorescence assay,but not by sero-neutralization test,in both rPRV-HA and Bartha-K61 groups.SIV-specific antibodies were detected by hemagglutination inhibition test only in rPRV-HA group 14 DPI.The rPRV-HA-immunized mice were protected from homologous SIV challenge,as indicated by limiting virus replication and pathological changes of the organs,and boosted antibody responses to SIV post-challenge.