Lymphocyte surface molecules - The tetraspanin superfamily

Tetraspanins represent a family of surface proteins whose immune function i s largely unknown. Here, Mark D. Wright and Kirsten L. Puls discuss two mem bers of this family. CD53 appears to function as a marker for positive sele ction of thymocytes and perhaps influences intrathymic migration, whereas C D37 may function in T- and B-cell responses to mitogens.