Cluster of Differentiation 48 (CD48), also known as SLAMF2, BCM-1 and BLAST-1, is a GPI-linked protein belonging to the CD2 subfamily of immunoglobulin superfamily molecules. CD2 and 2B4 (CD244) are known ligands for CD48. CD48 protein is expressed on most lineage-committed hematopoietic cells but not on hematopoietic stem cells or multipotent hematopoietic progenitors. CD48 protein performs biological functions in a variety processes including adhesion, pathogen recognition, cellular activation, and cytokine regulation, and emerges as a critical effector molecule in immune responses.