CD244 receptor (CD244 (also known as 2B4 or SLAMF4))

CD244 (2B4, SLAMF4) is a type-I transmembrane protein receptor that belongs to the signaling lymphocytic activation molecule (SLAM) family and the immunoglobulin superfamily[1][2][4]. CD244 is predominantly expressed on natural killer (NK) cells, T cells (especially CD8+ subsets), monocytes, eosinophils, dendritic cells, and some myeloid cells[1][2][4]. Its primary ligand is CD48, a GPI-anchored molecule also belonging to the SLAM family, expressed on hematopoietic cells[1][5]. CD244 transmits either activating or inhibitory signals depending on the availability of intracellular adaptor proteins: the SH2-domain containing protein SAP (SLAM-associated protein) mediates activation, while other molecules such as EAT2 or phosphatases (SHP1/SHP2) mediate inhibitory effects[1][2][4][7]. The interaction of CD244 with CD48 regulates NK and T cell cytotoxicity, cytokine production, and the maintenance of memory and effector cell populations[4][6]. CD244 function is implicated in viral immunity, cancer immunosurveillance, and autoimmunity. Altered expression or signaling through CD244 can be associated with immune exhaustion, as seen in chronic viral infections and some malignancies[1][4][7]. The dual (activating/inhibitory) nature of CD244 makes it a complex but potentially valuable target for immunotherapy and as a disease biomarker[2][3][4][7].

Other names

2B4SLAM family member 4SLAMF4Natural killer cell receptor 2B4

Modulation of immunity via activation or inhibition of NK and T cell responses through engagement with adaptor proteins (SAP, EAT2) and phosphatases Blockade or activation of CD244 to enhance or dampen immune cell cytotoxicity