Porcine parvovirus 1 (PPV1) is one of the most prevalent pathogens that can cause reproductive disorder in sows. The VP2
protein of PPV1 is the most important immunogenic
protein that induces
neutralizing antibodies and protective immunity. Thus, VP2 is considered an ideal target
antigen for the development of a genetically engineered PPV1
vaccine. In this study, the baculovirus transfer vector carrying the HR5-P10-VP2 expression cassette was successfully constructed with the aim of increasing the expression levels of the VP2
protein. The VP2
protein was confirmed using SDS‒PAGE and Western blot analyses. Electronic microscope analysis showed that the recombinant VP2
proteins were capable of self-assembling into VLPs with a diameter of approximately 25 nm. The immunogenicity of the VP2
subunit vaccine was evaluated in pigs. The results showed that VP2
protein emulsified with ISA 201VG adjuvant induced higher levels of HI
antibodies and
neutralizing antibodies than VP2
protein emulsified with IMS 1313VG adjuvant. Furthermore, the gilts immunized with the ISA 201VG 20 μg
subunit vaccine acquired complete protection against PPV1 HN2019
infection. In contrast, the commercial
inactivated vaccine provided incomplete protection in gilts. Therefore, the VP2
subunit vaccine is a promising genetically engineered
vaccine for the prevention and control of PPV1.