As an immunogen of coronavirus, nucleoprotein (N) is a potential antigen for serological monitoring of infectious bronchitis virus (IBV). In this report, recombinant N protein from the Beaudette strain of IBV was produced and purified from Escherichia coli as well as Sf9 (insect) cells HCP Elisa Kit 2G and used for enzyme-linked immunosorbent assay (ELISA) plate coating. ).

The N protein produced in Sf9 cells was phosphorylated while the E. coli N protein was not. Our data indicated that protein N purified from E. coli was more sensitive to anti-IBV serum than protein from Sf9 cells. The recombinant N protein did not react with antisera to other avian pathogens, implying that it was specific in recognizing antibodies against IBV.

Furthermore, data from the detection of field samples and IBV strains indicated that the use of the recombinant protein as a coating antigen could achieve performance equivalent to that of an ELISA kit based on extracts of infected material as a source of antigen(s). Recombinant protein-based ELISAs are safe (no live virus), clean (only virus antigens are present), specific (individual proteins can be used), and fast (to respond to new viral strains and strains that may not necessarily be easily cultivated).

Product Information

Product Type: ELISA Kit

Storage: All kit reagents 2°C to 8°C

Target Expression System: SF9

Species Group: Insect

Species: S. frugiperda

Assay format: 96-well plate

Time to result: ~2 hrs. 50 minutes

LOD: 0.3ng/mL

LLOQ: 0.5ng/mL

Recommended thinner: I028


This kit is designed to determine the presence of host cell protein (HCP) impurities in products made by recombinant expression in Sf9 insect host cells. This kit is a second-generation method that replaced our previous Sf9 Insect Cell HCP ELISA Kit (F020). Use Sample Diluent, Item # I028, with these kits; available separately.