PORCINE PARVOVIRUS 2 CAPSID PROTEIN 2 (INSECT CELLS), HIS-TAG

Porcine Parvovirus 2 (PPV2) capsid protein 2 is a recombinant antigen, manufactured to high purity using the baculovirus insect cell expression system.

PRODUCT DETAILS – PORCINE PARVOVIRUS 2 CAPSID PROTEIN 2 (INSECT CELLS), HIS-TAG

• N-terminal 6xHis tagged PPV2 capsid protein (585 aa) (Accession No. NP_757372.1).
• Recombinant protein purified from baculovirus-infected insect cells.
• Purified protein (selected band of the CsCl gradient) was dialyzed against Phosphate Buffer Saline (PBS), pH 7.4 to remove CsCl.
• Recombinant PPV-His-VP2 expression confirmed in infected cells by Western with α-His specific antibodies. Tested in ELISA with α-PPV specific antiserum.

BACKGROUND

Porcine parvovirus (PPV) causes reproductive failure in pregnant sows. The infection occurs without clinical symptoms in adults; however, the virus can cross the placental barrier during the infection and cause the death of the fetuses, stillbirths and return to estrus (Streck et al., 2020). PPV is also able to increase the effects of porcine circovirus type 2 infection in the clinical course of postweaning multisystemic wasting syndrome (PMWS), another significant disease in global swine production (Ouyang et al., 2019).

PPV2 (proposed name Ungulate tetraparvovirus 3), a member of the Tetraparvovirus genus, was discovered in 2001 during a survey for hepatitis E virus (HEV) in swine sera collected in Myanmar (Hijikata et al., 2001; Cságola et al., 2016). PPV is a small, non-enveloped, single-stranded, negative-sense DNA virus. Capsids of PPV are assembled from three viral proteins (VP1, VP2, and VP3). The capsid is a spherical shell (~ 28 nm in diameter) consisting of 60 identical copies of viral proteins arranged in an icosahedral symmetry. These identical copies (subunits) comprise about 90% of VP2 and 10% of VP1 molecules. The major structural protein, VP2 is the main target for neutralizing antibodies in PPV. Because VP2 is the main structural protein of PPV and constitutes most of the viral capsid, VP2 produced in vitro can self assemble into virus-like particles. For example, when VP2 is expressed using the baculovirus expression vector system, it assembles into virus-like particles (VLPs) similar in size and morphology to native virions and seen as a 64 kDa band by Western-blot analysis. PPV VP2 VLPs have been shown to induce antibodies against PPV in immunized pigs and rabbits. PPV-cell or tissue-tropism determinants, host-range determinants, and determinants that confer hemagglutination properties have all been shown to be located in the capsid proteins. PPV VP2 VLPs also exhibited positive immunoreactivity for PPV in a commercial ELISA (Mészáros et al., 2017; Zhou et al., 2010).

There are many advantages to the use of VLPs in vaccines and for diagnosis. Compared to inactivated virus, which is currently used in vaccines, they do not require the propagation of infectious virus, there is no risk of virus transmission or infection, production levels are much higher, production is cost effective, and VLPs are generally very stable (Zhou et al., 2010).

REFERENCES

• Cságola A, Zádori Z, Mészáros I, Tuboly T. Detection of Porcine Parvovirus 2 (Ungulate Tetraparvovirus 3) Specific Antibodies and Examination of the Serological Profile of an Infected Swine Herd. PLoS One. 2016 Mar 14;11(3):e0151036.
• Hijikata M, Abe K, Win KM, Shimizu YK, Keicho N, Yoshikura H. Identification of new parvovirus DNA sequence in swine sera from Myanmar. Jpn J Infect Dis. 2001 Dec;54(6):244-5.
• Mészáros I, Olasz F, Cságola A, Tijssen P, Zádori Z. Biology of Porcine Parvovirus (Ungulate parvovirus 1). Viruses. 2017 Dec 20;9(12):393.
• Streck AF, Truyen U. Porcine Parvovirus. Curr Issues Mol Biol. 2020;37:33-46.
• Zhou H, Yao G, Cui S. Production and purification of VP2 protein of porcine parvovirus expressed in an insect-baculovirus cell system. Virol J. 2010 Dec 10;7:366.