Document 0135
 DOCN  M9650135
 TI    In vitro culture of human peripheral blood monocytes induces hyaluronan
       binding and up-regulates monocyte variant CD44 isoform expression.
 DT    9605
 AU    Levesque MC; Haynes BF; Department of Medicine, Duke University Medical
       Center, Durham,; NC 27710, USA.
 SO    J Immunol. 1996 Feb 15;156(4):1557-65. Unique Identifier : AIDSLINE
       MED/96164586
 AB    CD44 is a cell surface proteoglycan homologous to cartilage link protein
       that serves as a receptor for hyaluronan (HA). CD44 isoforms include an
       unspliced 80- to 90-kDa standard form (CD44S) and isoforms derived from
       alternative splicing of nine CD44 variant exons (CD44V). Ligation of
       CD44 isoforms on monocytes induces the production of IL-1 and TNF-alpha.
       In addition, CD44 mAbs and HA inhibit HIV infection of monocytes by
       monocytotropic HIV, but do not inhibit T cell tropic HIV infectivity of
       T cells. To determine the ability of PB lymphocytes and monocytes to
       bind HA and to define and compare CD44 isoforms present on PB monocytes
       and lymphocytes, we studied PBMC using a panel of CD44 mAbs, HA-FITC,
       flow cytometry, and Western blot analysis. We found that freshly
       isolated PB monocytes and lymphocytes did not bind soluble HA. However,
       in vitro culture of PBMC for 8 to 16 h resulted in CD44-dependent
       HA-FITC binding to monocytes, but not to lymphocytes. Western blot and
       flow cytometry analyses using CD44 mAbs demonstrated selective
       expression of high m.w. CD44V isoforms on cultured monocytes, but not on
       lymphocytes. Finally, tissue macrophages and multinucleated giant cells
       from patients with inflammatory lesions expressed CD44V6- and
       CD44V9-containing CD44 isoforms in vivo, suggesting that CD44V
       expression is associated with differentiation of monocytes to tissue
       macrophages in vivo in inflammatory sites. Taken together, our data
       demonstrate that PB monocytes, but not T or B lymphocytes, acquire the
       ability to bind HA and up-regulate CD44V expression after in vitro
       culture.
 DE    Antigens, CD3/PHARMACOLOGY  Antigens, CD44/CHEMISTRY/*METABOLISM  Cells,
       Cultured  Flow Cytometry  Fluorescent Antibody Technique, Indirect
       Human  Hyaluronic Acid/*METABOLISM  Lymphocytes/METABOLISM
       Monocytes/*METABOLISM  Phytohemagglutinins/PHARMACOLOGY  Support, U.S.
       Gov't, P.H.S.  JOURNAL ARTICLE

       SOURCE: National Library of Medicine.  NOTICE: This material may be
       protected by Copyright Law (Title 17, U.S.Code).