Development and characterization of monoclonal antibodies to subgroup J avian leukosis virus

In an attempt to develop a specific diagnostic test Cut avian leukosis virus (A-LV) subgroup J (ALV-J) strain Hcl, four monoclonal antibodies (MAbs), JE9, G2, I45, and J47, were generated that are specific for ALV-J envelope glycoprotein, gp85, Polymerase chain reaction (PCR) was used to amplify, genomic pro-viral DNA of Avian Disease and Oncology Laboratory (ADOL)-Hcl and ADOL-4817 envelope genes. Both open reading frames encoding glycoproteins gp85 and gp37 were cloned into baculoviruses. Abundant expression of gp85 and gp37 was detected in the recombinant viruses with specific antibody to Hcl strain of the ALV J. The expressed proteins were used For immunization of mice to produce hybridoma cell lines secreting MAbs specific to ALV-J envelope protein, A panel of MAbs was generated by fusing NS1 myeloma cells and spleen cells from mice immunized with the recombinant baculoviruses. With the use of all immunofluorescence assay, three MAbs (JE9, G2, I45) reacted with ALV-J but not with subgroups A, B, C, D, or E of ALV. MAb J47 reacted with all exogenous subgroups of ALV including A, B, C, D, and J but not with endogenous subgroup E viruses. Western blot analysis was pct-Formed With all four MAbs against recombinant baculovirus and Hcl-infected chicken embryo fibroblast (CEF) lysates. A major band with a molecular weight about 90 kD corresponding to the size of ALV-J envelope was consistently obtained. With these MAbs, we detected the Hc I antigen ill CLI's infected with several ALV-J viruses isolated in the United States and also in tissue sections from chickens infected with Hcl strain of ALV-J. These MAbs will be useful reagents for the diagnosis of ALV-J infection because they recognize a common antigenic epitope in six isolates tested thus far.