Evaluation of synthetic peptides derived from glycoproteins gp45 and gp90 as candidates for the immunodiagnosis of equine infectious anemia.

The international scientific community continues to promote the development of diagnostic techniques with improved performance and novel capture antigens. On this basis, two synthetic peptides derived from gp45 and gp90 were evaluated to identify the best candidate for the indirect immunodetection of infection. In both assays, 68 serum samples from naturally infected horses in Granma Province (59 seropositive and 9 seronegative), previously classified using the agar gel immunodiffusion (AGID) test, were analyzed. The diagnostic performance of each candidate peptide was assessed by calculating sensitivity, specificity, positive predictive value, negative predictive value, and the Kappa coefficient. Compared with ELISAP15/gp90 and the AGID test, the ELISAP05/gp45 variant showed better performance, accurately identifying the highest number of infected animals (91.2%, 56/59). Consequently, it achieved high values for positive predictive value (98.2%), overall accuracy (94.1%), and Kappa coefficient (0.96; very good). The ability of synthetic peptide P05 to discriminate between infected and uninfected animals exceeded that of P15. Based on these results, synthetic peptide P05 may serve as an alternative capture antigen for evaluating the immune response in equine infectious anemia.