Differentiation of measles virus strains and a strain of canine distemper virus by monoclonal antibodies.

Monoclonal antibodies raised against the Hallé strain of measles virus were tested for their strain specificity using other measles virus isolates (Edmonston, Leningrad, Lec and two fresh isolates JT and Fasquelle). Monoclonal antibodies to L, HA and NP polypeptides, with one exception, reacted with all the measles virus strains tested; antibody from hybrid line 25 failed to react with the NP polypeptide of JT virus by immunofluorescence or radioimmunoprecipitation. Three other monoclonal antibodies, two reacting with NP and one with HA, although giving a positive immunofluorescence reaction, did not immunoprecipitate labelled antigen from JT virus-infected cells. The immunological relationship of canine distemper and measles viruses was also investigated with monoclonal antibodies. Two of the three anti-NP and three of the four anti-HA monoclonal antibodies reacted with canine distemper virus in an immunofluorescence reaction but only one (anti-NP) reacted in a radioimmunoprecipitation test.