CD5 Human, Sf9

CD5 (Human Recombinant, Sf9) is a single, glycosylated polypeptide chain consisting of 359 amino acids, with a molecular mass of approximately 40 kDa . The protein is expressed with a 6-amino acid His tag at the C-terminus, which aids in its purification through chromatographic techniques . The recombinant CD5 is produced in Sf9 cells, a type of insect cell line derived from the fall armyworm, using Baculovirus expression systems .

CD5 serves as a receptor involved in the regulation of T-cell proliferation and activation. It modulates the signals from the T-cell receptor (TCR) and B-cell receptor (BCR), playing a critical role in maintaining immune homeostasis . CD5 is also an important marker in immunohistochemistry for identifying T-cells and certain B-cell subsets .

In clinical settings, CD5 expression is used as a diagnostic marker for various hematological malignancies. Approximately 76% of T-cell neoplasms express CD5, making it a valuable marker for these cancers . It is also observed in chronic lymphocytic leukemia, hairy cell leukemia, and mantle cell lymphoma . Conversely, the loss of CD5 expression can indicate malignancy in conditions such as cutaneous T-cell lymphoma .

Recombinant CD5 produced in Sf9 cells is widely used in laboratory research for studying T-cell and B-cell functions, signaling pathways, and immune responses. Its high purity and stability make it suitable for various experimental applications, including flow cytometry, Western blotting, and immunoprecipitation .

CD5 (Human Recombinant, Sf9) is typically supplied as a sterile, filtered, colorless solution containing phosphate-buffered saline (pH 7.4) and 10% glycerol . For short-term storage, it can be kept at 4°C for 2-4 weeks. For long-term storage, it is recommended to store the protein at -20°C with the addition of a carrier protein such as 0.1% HSA or BSA to prevent degradation . It is important to avoid multiple freeze-thaw cycles to maintain the protein’s integrity .