Signaling Lymphocyte Activation Molecule family member F7 (SLAMF7 also called as CS1 or CRACC) is a member of the CD2 family. It is expressed on CD8+ cytotoxic T lymphocytes, activated B cells, NK cells and mature dendritic cells (Boles & Mathew 2001, Bouchon et al. 2001). It has been suggested that CS1 has both activating and inhibitory functions in NK cells. It may activate NK mediated cytotoxicity through an ERK-mediated pathway in a SAP-independent manner (Bouchon et al. 2001). Most of the CD2 members interact homophilically and CS1 is shown to be a self-ligand and that homophilic interaction regulate NK cell cytolytic activity (Kumaresan et al. 2002).