CD86, a costimulatory molecule expressed on antigen-presenting cells, critically modulates T cell activation via specific binding to CD28 or CTLA-4 on T cells. Although human and murine CD86 are well-characterized, avian CD86 remains unidentified and uncharacterized due to the lack of specific antibodies. In this study, we cloned and expressed the chicken CD86 (chCD86) gene, generated specific monoclonal antibodies (mAbs) against it, and characterized its expression pattern on chicken immune cells. Phylogenetic analysis showed that chCD86 has less than 35% amino acid homology with its mammalian counterparts. Recombinant chCD86 protein (rchCD86) was expressed in both E. coli and DF-1 cells, respectively, and the purified prokaryotic rchCD86 was used as an immunogen to generate three mAbs against chCD86. These mAbs can recognize natural chCD86 expressed on chicken monocytes/macrophages, as confirmed by indirect immunofluorescence assay (IFA) and Western blotting. Furthermore, flow cytometric analysis demonstrated that all mAbs detect chCD86 expression on approximately 7% of chicken KUL01⁺ leukocytes. Overall, we generated specific mAbs against chCD86 and delineated its expression profile on chicken immune cells. These reagents provide essential immunological tools for further investigation into the roles of chCD86-expressing cells in diseases and immunity.

To Cite This Article: He S, Yin S, Zhang H, Meng C, Cao J, Li H, Hao X and Shang S, 2025. molecular characterization and development of specific monoclonal antibodies against chicken CDA86. Pak Vet J. http://dx.doi.org/10.29261/pakvetj/2025.298