Mouse Leukosialin (SPN) Protein

Background

Sialophorin (SPN), also known as CD43, is a glycoprotein primarily expressed on the surface of immune cells, such as T lymphocytes, monocytes, neutrophils, and some B cells. SPN is involved in various aspects of immune cell function, including cell adhesion, migration, and activation. The molecule plays a critical role in modulating the interaction between immune cells and their microenvironment, particularly by regulating the adhesion properties of leukocytes, which are essential for their migration and trafficking through different tissues. Sialophorin is a highly sialylated protein, meaning it has many sialic acid residues attached to its extracellular portion, which contribute to its negative charge. This negative charge facilitates electrostatic repulsion between cells, which can prevent adhesion in certain contexts but also enables its participation in finely tuned immune responses. SPN is an important player in the immune system's ability to differentiate between self and non-self, contributing to immune surveillance and cellular interactions during inflammatory responses.