Establishment of a Fluorescent Microsphere Immunoassay Assay for H7 Subtype Avian Influenza Virus
In order to establish a simple,rapid and specific method to detect antibodies against H7 subtype avian influenza virus(AIV),mouse anti-chicken IgG was coupled with fluorescent microspheres,and sheep anti-mouse IgG and HA protein of recombinant H7 subtype AIV were sprayed on nitrocellulose membrane as quality control line(C line)and detection line(T line),respectively.The reaction system was optimized by single variable analysis,and its sensitivity,specificity,reproducibility as well as coincidence rate with hemagglutination inhibition(HI)test were evaluated.The results showed that the established method was twice more sensitive than the HI test established with reference to national standard;good specificity was observed,as it can't react with H5 subtype AIV,H9 subtype AIV,Newcastle disease virus(NDV),infectious bronchitis virus(IBV),infectious bursal disease virus(IBDV),egg drop syndrome virus(EDSV)and other common positive serum of avian disease pathogens;the variable coefficients of reproducibility test ranged from 3.13%to 8.46%,indicating a good repeatability;and the results detection by the established method were 95.67%consistent with those by HI test,indicating a high consistency.In conclusion,the established method with stable performance and reliable results could be used to rapidly detect antibodies against H7 subtype AIV as a new tool.