The invention provides a type A foot-and-mouth
disease nanoparticle antigen NP-AVPn, a preparation method and an application. The NP-AVPn provided by the invention is obtained by carrying out TEV
enzyme cracking on
intracellular self-assembled A type foot-and-mouth
disease nano-particle
antigen NP-AVPn-T, and then carrying out
nickel affinity chromatography purification to remove T fusion-promoting tag
protein, so that
antigen epitopes are fully exposed on the surface of nano-particle
carrier protein NP. According to the FMDVA type NP-AVPn
nanoparticle antigen disclosed by the invention, three structural proteins of FMDVA type VP1, VP2 and VP3 are simultaneously displayed in a
nanoparticle form, so that the FMDVA type NP-AVPn nanoparticle antigen can be simultaneously subjected to good and uniform reaction with antibodies generated after immunization or infection of three animals of pigs, cattle and sheep, and the problem that the FMDVA
type antigen is limited in source in FMDV
clinical diagnosis is solved. The invention also provides a vaccine developed based on the NP-AVPn nanoparticle antigen and an FMDVA type LB-ELISA
antibody detection kit, and the kit can be simultaneously used for quantitative detection of FMDVA
type specific antibodies from three different animals, namely pigs, cows and sheep, and has the advantages of high sensitivity, good specificity and high accuracy.