The CD5 protein, encoded by the CD5 gene, is a transmembrane glycoprotein predominantly expressed on T-cells and B-1a cells. The CD5 gene is on chromosome 11q23 and encodes a protein comprising approximately 495 amino acids, resulting in a molecular weight of around 67 kDa. CD5 undergoes various post-translational modifications, including phosphorylation, glycosylation, and the formation of disulfide bonds, which are crucial for its function. As a membrane protein, CD5 plays a significant role in modulating T-cell and B-cell signaling, promoting immune tolerance, and regulating lymphocyte activation and proliferation.
CD5 expression is primarily observed in lymphoid tissues, such as the spleen, thymus, and lymph nodes, as well as in circulating T-cells and B-1a cells. The expression of CD5 is tightly regulated during lymphocyte development and activation, with its levels influenced by various factors, including cytokines and antigen receptor signaling. The dysregulation of CD5 expression or mutations in the CD5 gene have been associated with autoimmune diseases, such as systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA), as well as certain lymphoid malignancies, including chronic lymphocytic leukemia (CLL) and mantle cell lymphoma (MCL).
In CLL, the accumulation of mature B-cells that co-express CD5 and other B-cell markers CD5 expression is a hallmark feature of the disease. Detection of CD5 expression on B-cells is essential for diagnosing CLL, aiding in distinguishing it from other B-cell lymphoproliferative disorders. Furthermore, CD5 expression in CLL has prognostic implications. CLL cases with higher levels of CD5 expression often correlate with more aggressive disease and poorer clinical outcomes. In other hematologic malignancies, such as mantle cell lymphoma (MCL), CD5 expression is also used as a diagnostic marker. MCL is characterized by the aberrant expression of CD5 on mature B-cells, which helps differentiate it from other types of non-Hodgkin lymphomas. Additionally, CD5 expression in MCL may have prognostic significance, with studies suggesting that higher levels of CD5 expression may be associated with more aggressive disease and poorer survival outcomes.
NeoBiotechnologies offers a variety of antibodies against CD5 that have been validated for flow cytometry, immunofluorescence, immunohistochemistry, and Western blotting. Additionally, we hold exclusive rights to CD5 antibodies available for licensing or collaboration [https://www.neobiotechnologies.com/gene-name/cd5/ ].
Synonyms
T-cell surface glycoprotein CD5, Lymphocyte antigen T1/Leu-1, CD5 antigen (p56 62), LEU1, Ly12, LyA, Lymphocyte antigen T1/Leu-1, T-cell surface glycoprotein CD5
Research Areas
B Cell Markers, Hematopoietic Stem Cells
