TY - JOUR
T1 - CS1, a novel member of the CD2 family, is homophilic and regulates NK cell function
AU - Kumaresan, Pappanaicken R.
AU - Lai, Wayne C.
AU - Chuang, Samuel S.
AU - Bennett, Michael
AU - Mathew, Porunelloor A.
N1 - Funding Information:
Research supported by NIH Grant CA85753.
PY - 2002/9/15
Y1 - 2002/9/15
N2 - CS1 is a novel member of the CD2 subset of immunoglobulin superfamily (IgSF) expressed on NK, T and stimulated B cells. The cytoplasmic domain of CS1 contains immunoreceptor tyrosine-based switch motif (ITSM) which is present in 2B4, SLAM and CD84. The signaling adaptor molecule SAP/SH2D1A, the defective gene in X-linked lymphoproliferative disease (XLPD), binds to ITSM and regulates immune cell function. However, recent studies indicate that CS1 may be regulated by a SAP-independent mechanism. In this study, we have examined the ligand specificity of CS1 and the effect of CS1 interaction with its ligand on the cytolytic activity of YT, a human NK cell line. Recombinant fusion protein, CS1-Ig, containing the CS1 extracellular domain and Fc portion of the human IgG bound cells transfected with CS1. CS1-Ig did not show any binding to cells expressing other members of the CD2 family. The cytolytic activity of YT was enhanced in presence of soluble CS1-Ig fusion protein. These results demonstrate that CS1 is a self-ligand and homophilic interaction of CS1 regulates NK cell cytolytic activity.
AB - CS1 is a novel member of the CD2 subset of immunoglobulin superfamily (IgSF) expressed on NK, T and stimulated B cells. The cytoplasmic domain of CS1 contains immunoreceptor tyrosine-based switch motif (ITSM) which is present in 2B4, SLAM and CD84. The signaling adaptor molecule SAP/SH2D1A, the defective gene in X-linked lymphoproliferative disease (XLPD), binds to ITSM and regulates immune cell function. However, recent studies indicate that CS1 may be regulated by a SAP-independent mechanism. In this study, we have examined the ligand specificity of CS1 and the effect of CS1 interaction with its ligand on the cytolytic activity of YT, a human NK cell line. Recombinant fusion protein, CS1-Ig, containing the CS1 extracellular domain and Fc portion of the human IgG bound cells transfected with CS1. CS1-Ig did not show any binding to cells expressing other members of the CD2 family. The cytolytic activity of YT was enhanced in presence of soluble CS1-Ig fusion protein. These results demonstrate that CS1 is a self-ligand and homophilic interaction of CS1 regulates NK cell cytolytic activity.
KW - CD2 subfamily
KW - Cytotoxicity
KW - Homophilic interactions
KW - NK cells
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U2 - 10.1016/S0161-5890(02)00094-9
DO - 10.1016/S0161-5890(02)00094-9
M3 - Article
C2 - 12213321
AN - SCOPUS:0037105245
SN - 0161-5890
VL - 39
SP - 1
EP - 8
JO - Molecular Immunology
JF - Molecular Immunology
IS - 1-2
ER -