Establishment of High-sensitivity Rapid Fluorescence Quantitative Detection Method for Antibody against Peste des Petits Ruminants Virus.

[Objectives] This study was conducted to establish a rapid quantitative method for detecting antibody against Peste des Petits Ruminants Virus (PPR V) in sheep serum. [Methods] Soluble N protein and NH fusion protein were obtained in Escherichia coli prokaryotic expression system by optimizing codons and expression conditions of E. coli. Furthermore, based on the purified soluble N protein and NH fusion protein, a high-sensitivity fluorescence immunoassay kit for detecting the antibody against PPR V was established. [Results] The method could quickly and quantitatively detect PPR V antibody in sheep serum, with high sensitivity and specificity, without any cross reaction to other related sheep pathogens. The intra-batch and inter-batch coefficients of variation were less than 10% and 15%, respectively, and the method had good repeatability. Through detection on 292 clinical serum samples, it was compared with the French ID VET competitive ELISA kit, and the coincidence rate of the two methods reached 93. 84%. Compared with the serum neutralization test, the detected titer value of the high-sensitivity rapid fluorescence quantitative detection method was basically consistent with the tilter value obtained by the neutralization test on the standard positive serum (provided by the WOAH Brucellosis Reference Laboratory of France). [Conclusions] This method can realize rapid quantitative detection of PPR V antibody on site, and has high practical value and popularization value. [ABSTRACT FROM AUTHOR]