Expression of Pseudorabies Virus Escherichia coli Strain BL21 and PRV gE-ELISA gE Core Epitopes in Utilization of Indirect

Pseudorabies virus glycoprotein E( PRV gE) has been recognized as a suitable diagnostic antigen for pseudorabies. In order to produce gE antigen in large quantities and at low cost,a gene fragment encoding PRV gE core epitopes was expressed in E. coli BL21 expression system. SDS-PAGE and Western Blotting revealed that the expression product in culture supernatant of E. coli BL21 was a recombinant protein,approximately 51. 8 Kd. At 5 h post-induction,protein concentration assay showed that the expression product amounted to 1. 65 mg /ml,accounting for 24. 17% of total proteins in the culture supernatant. An indirect PRV gE-ELISA was established by using the recombinant expression product as a coating antigen. Cross-reactivity assay showed that this antigen was PRV specific. In addition,the assay was consistently reproducible. Comparison of detection results of 240 serum samples between PRV gE-ELISA and a commercially available PRV diagnostic kit showed that there was no significant difference between these two methods( P > 0. 05).