CD48 (also known as SLAMF2) is a glycosylphosphatidylinositol (GPI)-anchored cell surface protein and a member of the signaling lymphocyte activation molecule (SLAM) family. It is expressed on various immune cells, including T cells, B cells, and natural killer (NK) cells. CD48 interacts with several ligands, such as CD2 and CD244 (2B4), to mediate immune cell adhesion, activation, and signaling. These interactions play crucial roles in T cell activation, NK cell cytotoxicity, and immune synapse formation. In disease contexts, CD48 expression is often upregulated in inflammatory conditions and certain cancers, such as acute myeloid leukemia (AML), where it may influence immune evasion and tumor progression. Additionally, CD48 has been identified as a potential biomarker and therapeutic target in autoimmune diseases, allergic conditions, and cancer immunotherapy.