Leukocyte Common Antigens (also known as CD45 or protein tyrosine phosphatase receptor type C) refer to a group of cell surface glycoproteins found on leukocytes, which are white blood cells involved in the immune response.
These antigens play a crucial role in the function and identification of leukocytes. They are divided into different isoforms, including CD45RA, CD45RB, CD45RC, CD45RO, and CD45RABC. Each isoform has a distinct pattern of expression and plays a unique role in the immune system.
Leukocyte Common Antigens are involved in various functions of leukocytes, including immune cell maturation, activation, and adhesion. They have a critical role in signal transduction, where they act as phosphatases by regulating the phosphorylation state of tyrosine residues in target proteins. This modulation of protein phosphorylation is essential for the activation or inhibition of specific signaling pathways involved in immune responses.
Furthermore, the expression of Leukocyte Common Antigens can be used as a marker to distinguish between different types of leukocytes. By utilizing specific antibodies that bind to these antigens, researchers and clinicians can identify and isolate different subpopulations of leukocytes within a heterogeneous mixture. This is helpful in both clinical diagnosis and research settings, as it allows for the identification and characterization of specific immune cell types.
Overall, Leukocyte Common Antigens are essential cell surface markers found on leukocytes that aid in their identification, activation, and signaling. They are critical components of the immune system and play a vital role in immune responses.
