CD8A Human

CD8A is a single-pass type I membrane protein. It typically forms a heterodimer with CD8B, another glycoprotein, to enhance the TCR’s ability to recognize and bind to MHC class I molecules . This interaction is essential for the activation and function of CTLs, which are responsible for killing infected or cancerous cells.

The extracellular domain of CD8A is involved in binding to MHC class I molecules, while the intracellular domain interacts with signaling molecules such as the src kinase Lck and the adaptor protein LAT (Linker for Activation of T cells) . These interactions are crucial for the signal transduction pathways that lead to T-cell activation and the subsequent immune response.

Recombinant human CD8A is produced using various expression systems, including Chinese Hamster Ovary (CHO) cells . The recombinant protein is often tagged with polyhistidine (His) or Fc regions to facilitate purification and detection . The recombinant form retains the functional properties of the native protein, making it useful for research and therapeutic applications.

Production and Purification: The DNA sequence encoding the extracellular domain of human CD8A is cloned into an expression vector and introduced into host cells. The recombinant protein is then purified using affinity chromatography techniques, such as His-tag or Fc-tag purification .

Applications: Recombinant human CD8A is widely used in immunological research to study T-cell activation, antigen recognition, and immune responses. It is also used in the development of immunotherapies and diagnostic assays .

Recombinant human CD8A is typically lyophilized and stored at -20°C to -80°C to maintain its stability . It is recommended to avoid repeated freeze-thaw cycles to preserve the protein’s integrity. Upon reconstitution, the protein should be stored under sterile conditions and used within a specified timeframe to ensure its activity .