CD8A encodes the CD8α chain, a transmembrane glycoprotein that serves as a co-receptor for the T cell receptor (TCR), binding to MHC class I molecules to mediate antigen-specific immune responses . Due to its critical role in cytotoxic T lymphocyte function, CD8A is extensively studied in immunology and oncology. Non-human primates, particularly cynomolgus monkeys (Macaca fascicularis), are the preferred preclinical model for evaluating immunotherapies given their close phylogenetic relationship to humans. Cynomolgus CD8A shares high protein sequence identity with its human ortholog , yet species-specific differences can affect cross-reactivity of therapeutic antibodies and functional assays . Therefore, establishing a human cell line stably overexpressing cynomolgus CD8A provides a valuable in vitro platform. This tool enables the screening of cross-reactive biologics, comparative analysis of receptor-ligand interactions, and functional studies of T-cell co-receptor signaling, thereby bridging the gap between murine models and human clinical applications.
