Evaluation of mouse monoclonal antibodies raised against an isolate of the variant avian paramyxovirus type 1 responsible for the current panzootic in pigeons

Summary Nine monoclonal antibodies raised against pigeon variant avian paramyxovirus type 1 isolate pigeon/England/617/83 were tested for their ability to react with classical and other pigeon variant isolates. Two of the monoclonal antibodies appeared to be specific for 617/83 reacting with no other virus. The remaining seven monoclonal antibodies bound to cells infected with all other pigeon isolates in indirect immunoperoxidase (IIP) tests but four distinct groups of other PMV-1 viruses were formed on the basis of the binding patterns. One of the monoclonal antibodies 161/617 caused haemagglutination inhibition (HI) of all the pigeon isolates tested but none of the other PMV-1 viruses and these results reflected the IIP results with this monoclonal antibody.161/617 was also shown to inhibit viruses of the avian paramyxovirus type 3 serogroup in HI tests. This reaction and the ability to bind to infected cells in IIP tests appeared to be restricted to PMV-3 viruses isolated from exotic birds and did not occur with viruses of ostensively the same serotype from turkeys.