Antigenic differences in the H proteins of canine distemper viruses

Antigenic properties between new Japanese field isolates and vaccine strain s of canine distemper virus (CDV) have been compared using four monoclonal antibodies (MAbs) (JD-5, JD-7, JD-11 and d-7) against the hemagglutinin (H) proteins of CDV, JD-5, JD-7 and JD-11 are newly established antibodies. Th ree MAbs, namely d-7, JD-5 and JD-11, reacted similarly to all the CDV stra ins examined. However, JD-7 reacted much more strongly with the vaccine str ains and an old field isolate than the recent field isolates in immunofluor escence, radio immunoprecipitation and virus neutralization assays. These r esults indicate that an antigenic region in the H protein, concerned with n eutralization and recognized by JD-7, has been altered in the recent field isolates. (C) 2000 Elsevier Science B.V. All rights reserved.