Objective: In order to get a rapid specific diagnostic reagent for subgroup A Avian Leukosis Virus detection.
Methods: The Avian Leukosis Virus Subgroup A (ALV-A) SDAU09E1 strain was inoculated into DF1 cells, an ALV-A- gp85 DNA fragment of 1023 bp was amplified from infected cells and inserted into PET-32a(+) plasmid at the location between restriction endonucleases BamH I and Not I sites. The recombinant plasmid PET-SDAU09E1 -gp85 was transformed into E coli. BL21 (Rosetta) for gp85 gene expression. Then we used the purified recombinant fusion protein to immunize 6 weeks old Kunming white mice, and the antiserum were prepared.
Results: The recombinant ALV-A gp85 fusion protein with a molecular weight of 52.8 kDa demonstrated a good antigenecity. Mon-specific serum produced by vaccinated mice came out reactive with subgroups A and B ALV (ALV-A and ALV-B but not subgroup J ALV) by the indirect immunofluorescence (IFA) method.
Conclusion: This was the first time to demonstrate a mono-specific antiserum specific to ALV-A and ALV-B, it could be used for differential diagnosis of exogenous ALV infections in CEF cultures when in complement with ALV-J specific monoclonal antibodies. Chickens in our country are now distressed by both classic ALV-A/B and emerging ALV-J, making differential diagnosis necessary, so studying this reagent has high practical value.