Expression and purification of Suid Herpesvirus-1 glycoprotein E in the baculovirus system and its use to diagnose Aujeszky’s disease in infected pigs

Abstract

Suid Herpesvirus 1 (SHV-1) is the etiological agent of Aujeszky’s disease (AD), which affects swine herds worldwide and causes substantial economic losses due to animal mortality and lost productivity. In order to eradicate SHV-1, vaccination programs using viruses lacking the gene encoding glycoprotein E (gE) are ongoing in several countries. These eradication programs have generated a currently unmet demand for affordable and sensitive tests that can detect SHV-1 infection, yet distinguish between infected and vaccinated pigs. To meet this demand, we used the baculovirus-insect cell system to produce immunologically authentic full-length recombinant gE protein for use in a serum ELISA assay. As previous efforts to clone the gE gene had failed due to its extremely high GC-content (75% average), we used betaine as a PCR enhancer to facilitate amplification of the entire gE gene from the Argentinian CL15 strain of SHV-1. The cloned gE gene was expressed at high levels in recombinant baculovirus-infected insect cells and reacted strongly with sera from SHV-1 infected pigs. We used the recombinant gE protein to develop a local indirect ELISA test with sensitivity and specificity comparable to currently available commercial tests. Thus, recombinant gE produced in baculovirus-infected insect cells is a viable source of antigen for the detection of SHV-1 in ELISA tests. We also provide evidence supporting a potential application of this recombinant form of gE as a SHV-1 subunit vaccine.

Isolation and characterization of a novel strain (YH01) of Micropterus salmoides rhabdovirus and expression of its glycoprotein by the baculovirus expression system

“…The optimized cell amount continued with a high level of expression of MSRV glycoprotein. Similar protein expression systems have been constructed for the expression of specific proteins, such as the recombi-nant glycoprotein of western equine encephalitis virus, GP5 glycoprotein of porcine reproductive and respiratory syndrome virus (PRRSV), E envelope glycoprotein of Japanese encephalitis virus, Suid Herpesvirus-1 glycoprotein E, and other viral proteins, and the recombinant proteins displayed virion-like bioactivity (Grabowska et al, 2009;Toth et al, 2011;Xu et al, 2011Xu et al, , 2012Serena et al, 2013). The silkworm-BEV system could become a valuable tool for producing high-quality recombinant glycoproteins.…”

Detection of pseudorabies virus antibody in swine oral fluid using a serum whole-virus indirect ELISA

“…30 In domestic pigs ( Sus scrofa domesticus ), the clinical expression of PRV infection ranges from inapparent to nearly 100% mortality in susceptible piglets. 35,37,43 Typical of herpesviruses, PRV establishes latency in pigs that survive acute infection, with virus subsequently detectable in trigeminal ganglion, olfactory bulb, and tonsil tissues. 13,31,34,36…”

“…30 In domestic pigs (Sus scrofa domesticus), the clinical expression of PRV infection ranges from inapparent to nearly 100% mortality in susceptible piglets. 35,37,43 Typical of herpesviruses, PRV establishes latency in pigs that survive acute infection, with virus subsequently detectable in trigeminal ganglion, olfactory bulb, and tonsil tissues. 13,31,34,36 Beginning in the 1960s, clinical PRV became increasingly problematic in commercial swine herds in Europe, the Americas, and Southeast Asia, with annual losses estimated at US$21 to $25 million to U.S. producers.…”

Enhancing expression of the pseudorabies virus glycoprotein E in yeast and its application in an indirect sandwich ELISA

“…The development of an indirect PRV gE enzyme‐linked immunosorbent assay (ELISA) using baculovirus (Serena et al . ) or yeast (Ao et al . ) expressing gE has been reported.…”