Diagnostic and prognostic potential of antibodies against O-acetylated sialic acids in canine visceral leishmaniasis

Employing bovine submaxillary mucin (BSM) as the coating agent, an enzyme-l inked immunosorbent assay (BSM-ELISA) was developed to detect antibodies di rected against O-acetylated sialic acids (O-AcSA) in canine visceral leishm aniasis (CVL). Serum samples were collected from 50 dogs previously screene d by a parasite-ELISA to detect anti-leishmanial antibodies and designated as seropositive (n = 30) and seronegative (n = 20). The BSM-ELISA detected anti-O-AcSA antibodies in 29 out of 30 seropositive dogs and was negative i n 15 out of 20 seronegative dogs; the sensitivity and specificity of the as say being 96.6% and 75%, respectively. Seven dogs from an endemic area in c entral Israel were longitudinally monitored for 15 months clinically, serol ogically and cultured for parasite. The levels of antibodies directed again st O-AcSA increased with the appearance of clinical symptoms and/or seropos itivity, disappeared when the disease was self-limiting as also with chemot herapeutic response and reappeared with relapse. The BSM-ELISA, therefore, represents a valuable tool for assessment of disease progression. (C) 1999 Elsevier Science B.V. All rights reserved.