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Studies on heterologous protection between Japanese type 1 and type 2 porcine reproductive and respiratory syndrome virus isolates.

ABSTRACT: The objective of the present study was to evaluate the cross-protective immunity between type 1 and type 2 porcine reproductive and respiratory syndrome virus (PRRSV) isolates in growing pigs. Japanese type 1 PRRSV, first isolated from a pig with respiratory disorders in a farm in 2009, exhibits unique genetic characteristics. The pathogenicity of a Japanese standard strain of type 2 PRRSV, EDRD1, in pigs immunized by the type 1 PRRSV isolate, Jpn EU 4-37 was determined by evaluating clinical signs, viremia, antibody response, and pathological lesions. Similarly, we evaluated the pathogenicity of Jpn EU 4-37 in pigs immunized by EDRD1 and compared the cross-protective immunity between these isolates. The EDRD1 challenge after Jpn EU 4-37 inoculation reduced viral clearance and shedding in pigs, compared to those treated with the EDRD1 single infection. On the other hand, the pathogenicity of Jpn EU 4-37 after EDRD1 infection did not differ significantly compared to non-immunized pigs treated with Jpn EU 4-37. Therefore, exposure to Jpn EU 4-37 could not induce enough immunity to reduce the viremia against subsequent infection by type 2 PRRSV. However, the immunity induced by Jpn EU 4-37 infection may play a role in reducing viremia caused by type 2 PRRSV. Moreover, the immunity induced by the EDRD1 and other genetically related viruses, which are broadly distributed in Japan, may not contribute to cross-protection against Jpn EU 4-37 as an emerging virus.

SUBMITTER: Iseki H

PROVIDER: S-EPMC7399305 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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Studies on heterologous protection between Japanese type 1 and type 2 porcine reproductive and respiratory syndrome virus isolates.

Iseki Hiroshi H Kawashima Kenji K Takagi Michihiro M Shibahara Tomoyuki T Mase Masaji M

The Journal of veterinary medical science 20200522 7

The objective of the present study was to evaluate the cross-protective immunity between type 1 and type 2 porcine reproductive and respiratory syndrome virus (PRRSV) isolates in growing pigs. Japanese type 1 PRRSV, first isolated from a pig with respiratory disorders in a farm in 2009, exhibits unique genetic characteristics. The pathogenicity of a Japanese standard strain of type 2 PRRSV, EDRD1, in pigs immunized by the type 1 PRRSV isolate, Jpn EU 4-37 was determined by evaluating clinical si ...[more]

PMID: 32448816

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Dataset Information

Studies on heterologous protection between Japanese type 1 and type 2 porcine reproductive and respiratory syndrome virus isolates.

Publications

Studies on heterologous protection between Japanese type 1 and type 2 porcine reproductive and respiratory syndrome virus isolates.

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