COMPARISON OF SEROLOGICAL TESTS FOR THE DIAGNOSIS OF FELINE IMMUNODEFICIENCY VIRUS-INFECTION OF CATS

A new enzyme-linked-immunosorbent assay (ELISA) for the detection of a ntibodies to feline immunodeficiency virus was compared with previousl y described ELISAs. Serum samples from 184 infected or uninfected cats were tested using a whole virus lysate kit and ELISAs based on recogn ition of one of two synthetic peptides (P237 and P253) localized in th e transmembrane domain of the viral envelope. The whole virus lysate c ommercial kit led to the detection of 6% false positive and 4.3% false negative sera. The ELISA based on peptide P253 gave no false positive result and failed to detect only one serum that was subsequently show n to be positive by radio-immunoprecipitation assay. A sandwich-ELISA test using Galanthus nivalis agglutinin, a lectin that specifically bi nds terminal mannose groups of the envelope proteins was used as a con firmatory test for equivocal results with peptide ELISA and gave simil ar results. This study indicates that recognition of P253 could serve as a sensitive and specific test for the diagnosis of seropositivity t o feline immunodeficiency virus, and moreover that the Galanthus nival is ELISA could be useful in equivocal cases as a confirmatory test.