Antigenic variation in avian paramyxovirus type 3 isolates detected by mouse monoclonal antibodies.

Six mouse monoclonal antibodies raised against PMV-3/turkey/England/ MPH/81 were used to assess relationships between PMV-3 viruses isolated from exotic birds and from domestic turkeys. Twelve PMV-3 isolates from birds held in quarantine in Great Britain and nine isolates from exotic birds in Netherlands, USA, Belgium, France and F.R. Germany were inhibited by only one monoclonal antibody, 50/1412, in haemagglutination inhibition tests. In contrast PMV-3 isolates from turkeys in England and France were inhibited to high titres by all six monoclonal antibodies. Two isolates from North American turkeys and one from a turkey poult in the Federal Republic of Germany were inhibited only by monoclonal antibody 50/1412 and, to low titres, by one other monoclonal antibody. Monoclonal antibody, 50/1412, showed no inhibition of 12 varied PMV-1 strains or representatives of other avian paramyxovirus sero-types and may be useful in the differential diagnosis of PMV-3 viruses.