CMV-CD81-mCherry-FLAG Lentivirus

The CMV-CD81-mCherry-FLAG lentivirus is a versatile expression vector designed for robust and stable expression of fluorescent and epitope-tagged CD81 protein under the control of the human CMV promoter. Utilizing a lentiviral backbone, this vector enables efficient genomic integration in both dividing and non-dividing cells, generating long-term stable, homogeneous reporter cell populations with a single transduction. The fusion of CD81 with mCherry provides a bright, photostable red fluorescent signal with minimal spectral overlap with GFP-based reporters, making it ideal for multiplex imaging and high-content analysis. The addition of a small C-terminal FLAG epitope tag enhances immunochemical detection versatility, allowing for sensitive detection, enrichment, and downstream biochemical analysis while minimizing steric hindrance.

This vector is ideally suited for applications requiring stable, real-time visualization and quantitative assessment of CD81 biological function. Researchers can track the localization and dynamics of CD81 on the plasma membrane, study tetraspanin-rich microdomains, and investigate trafficking, endocytosis, and recycling pathways in live cells. In extracellular vesicle and exosome research, the red fluorescent signal facilitates visualization of CD81-positive vesicle formation and release, while the FLAG tag allows for antibody-based detection and enrichment of CD81-containing cellular components, providing orthogonal validation of imaging results. This system is valuable for mechanistic studies in immunology and oncology, where CD81 is involved in immunological synapse formation, cell adhesion, and migration, and can be used to generate stable reporter cell lines from organoids or primary cell derivatives for monitoring long-term phenotypes. In drug discovery and functional genomics, the fluorescent signal can be used for high-content or flow cytometry-based screening to identify modulators of membrane structures or CD81-related signaling pathways, while the epitope tag supports downstream proteomics workflows such as immunoprecipitation to map interaction networks.