Cloning from purified high endothelial venule cells of hevin, a close relative of the antiadhesive extracellular matrix protein SPARC.
High endothelial venules (HEV) in lymphoid tissues support high levels of lymphocyte extravasion from the blood. We purified high endothelial cells from human tonsils by immunomagnetic selection with MECA-79 MAb to construct an HEV cDNA library. Differential screening of this library using cDNA probes from HEV (plus) or flat-walled vessel (minus) endothelial cells allowed us to characterize a novel human cDNA expressed to high levels in HEV. The cDNA encodes a secreted acidic calcium-binding glycoprotein of 664 aa residues, designated hevin, exhibiting 62% identity with the antiadhesive extracellular matrix protein SPARC, over a region of 232 aa spanning more than four fifths of the SPARC coding sequence. The primary structure and sequence of hevin and similar to SPARC-like proteins from rat and quail, called SC1 or QR1. Hevin could contribute to the induction or maintenance of features of the HEV endothelium that facilitate lymphocyte migration.
Girard
J P
JP
Center for Blood Research, Harvard Medical School, Boston, Massachusetts 02115, USA.
Springer
T A
TA
D020410:Activated-Leukocyte Cell Adhesion Molecule; D000595:Amino Acid Sequence; D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D001483:Base Sequence; D002135:Calcium-Binding Proteins / Q000737:chemistry / Q000235:genetics* / Q000276:immunology; D002448:Cell Adhesion; D003001:Cloning, Molecular; D003370:Coturnix; D018076:DNA, Complementary / Q000235:genetics; D004730:Endothelium, Vascular / Q000166:cytology / Q000378:metabolism*; D016326:Extracellular Matrix Proteins / Q000737:chemistry; D005136:Eye Proteins / Q000737:chemistry; D005455:Fluorescent Antibody Technique; D015723:Gene Library; D005796:Genes; D006023:Glycoproteins / Q000737:chemistry / Q000235:genetics* / Q000276:immunology; D006801:Humans; D018189:Immunomagnetic Separation; D017403:In Situ Hybridization; D008969:Molecular Sequence Data; D005810:Multigene Family; D009419:Nerve Tissue Proteins / Q000737:chemistry; D015676:Osteonectin / Q000737:chemistry*; D014066:Palatine Tonsil / Q000166:cytology; D012333:RNA, Messenger / Q000235:genetics; D051381:Rats; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D014471:Umbilical Veins
D020410:Activated-Leukocyte Cell Adhesion Molecule; D000911:Antibodies, Monoclonal; D002135:Calcium-Binding Proteins; D018076:DNA, Complementary; D016326:Extracellular Matrix Proteins; D005136:Eye Proteins; D006023:Glycoproteins; D009419:Nerve Tissue Proteins; D015676:Osteonectin; C091516:QR1 protein, Coturnix japonica; D012333:RNA, Messenger; C503126:SPARCL1 protein, human; C503128:Sparcl1 protein, rat