A novel ligand for CD44 is serglycin, a hematopoietic cell lineage-specific proteoglycan. Possible involvement in lymphoid cell adherence and activation.
The lymphocyte adhesion molecule CD44 recognizes a non-hyaluronate proteoglycan, gp600, secreted by mouse T cell line CTLL2. We now demonstrate that gp600 is identical to serglycin, a member of the small proteoglycan family stored in intracellular secretory granules of lymphoid, myeloid, and some tumor cells. Purified gp600 has the ability to bind specifically to CD44, and the binding is dependent on activation of CD44. The CD44-binding elements on gp600 or serglycin are glycosaminoglycans consisting of chondroitin 4-sulfate. Serglycin is readily exocytosed, and its interaction with active form CD44 augments the CD3-dependent degranulation of CD44 positive CTL clones. We conclude that the serglycin secreted from secretory granules of hematopoietic cells is a novel ligand for CD44, and could regulate lymphoid cell adherence and activation.
Toyama-Sorimachi
N
N
Department of Immunology, Tokyo Metropolitan Institute of Medical Science, Japan.
Sorimachi
H
H
Tobita
Y
Y
Kitamura
F
F
Yagita
H
H
Suzuki
K
K
Miyasaka
M
M
D000595:Amino Acid Sequence; D000818:Animals; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D002352:Carrier Proteins / Q000276:immunology / Q000378:metabolism*; D002448:Cell Adhesion; D002460:Cell Line; D002852:Chromatography, Ion Exchange; D017077:Culture Media, Conditioned; D003594:Cytoplasmic Granules / Q000378:metabolism; D004187:Disaccharides / Q000737:chemistry / Q000302:isolation & purification; D005455:Fluorescent Antibody Technique; D006025:Glycosaminoglycans / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D006412:Hematopoietic Stem Cells / Q000378:metabolism*; D018960:Hyaluronan Receptors; D008024:Ligands; D008213:Lymphocyte Activation; D008407:Mast Cells / Q000378:metabolism*; D051379:Mice; D008969:Molecular Sequence Data; D011485:Protein Binding; D011509:Proteoglycans / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D011956:Receptors, Cell Surface / Q000276:immunology / Q000378:metabolism*; D016201:Receptors, Lymphocyte Homing / Q000276:immunology / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid; D013601:T-Lymphocytes / Q000276:immunology; D033921:Vesicular Transport Proteins
D002352:Carrier Proteins; D017077:Culture Media, Conditioned; D004187:Disaccharides; D006025:Glycosaminoglycans; D018960:Hyaluronan Receptors; D008024:Ligands; D011509:Proteoglycans; D011956:Receptors, Cell Surface; D016201:Receptors, Lymphocyte Homing; D033921:Vesicular Transport Proteins; C075430:serglycin