Serodiagnosis of equine infectious anemia by indirect ELISA based on a novel synthetic peptide derived from gp45 glycoprotein.

The transmembrane glycoprotein gp45 (implicated in virus-equine B lymphocyte binding and in subsequent infection) is an important protein used as an antigen in the serological diagnosis of equine infectious anemia, but synthetic peptides derived from its structure are not. Consequently, the present study aimed to determine the diagnostic performance of the Bio-AIELAB immunoassay (novel synthetic peptide P05/gp45) in comparison with a similar commercial assay (ELISA EIA, VMRD Inc, USA) and with the gold standard (AGID, LABIOFAM, Cuba). A total of 365 samples of sera from naturally infected Cuban horses (positive: 179, and negative: 186) were investigated by Bio-AIELAB and AGID, of which 299 (positive: 147, and negative: 152) were analysed by ELISA EIA. The performance indicators used in all cases were: relative diagnostic sensitivity and specificity, positive and negative predictive values, as well as concordance according to the Kappa index. The Bio-AIELAB system obtained the best performance in sensitivity (99.44%, 178/179), specificity (95.16%, 177/186) and concordance (Kappa index: 0.94) with respect to ELISA EIA test. Based on the above elements, Bio-AIELAB could be a promising candidate for use in equine infectious anemia surveillance programs in combination with the AGID test.