Visual typing detection of bovine leukemia virus with a lateral flow immunoassay based on latex microspheres

Bovine Leukemia Virus (BLV), a member of the genus Deltaretrovirus, cause chronic tumor-related diseases in bovine and posing a significant threat to bovine industry. Currently, the detection of BLV mainly relies on agar gel immunodiffusion (AGID) and enzyme-linked immunosorbent assay (ELISA). However, these methods are limited by their complex procedures, long processing times, and high costs, making them unsuitable for rapid onsite diagnosis. In this study, a lateral flow immunoassay (LFIA) was established based on the BLV gp51 protein employing latex microsphere (LM) as signal labels was developed for the rapid and sensitive detection of bovine derived BLV. This method can detect the positive standard serum at a dilution of 1:256. A parallel analysis in 138 bovine serum samples were confirmed by LFIA and commercial ELISA kits, showed strong correlation with reference methods and no cross-reactivity with other bovine pathogens. The LFIA exhibited high relative sensitivity (87.09%) and specificity (99.06%), and concordance rate of the LFIA and ELISA was 96.37% (kappa = 0.89), indicating the practical reliability of the LFIA. The LFIA remained consistent accuracy and functionality at least 90-day at 4 ℃ or 70-day at 37 ℃. Our proposed approach provided an efficient solution for rapid on-site and visual screening in resource limited environment Therefore, the LFIA has a great potential for BL diagnosis and prevention.