Cutting edge: an inducible sialidase regulates the hyaluronic acid binding ability of CD44-bearing human monocytes.
Previous studies established that variable degrees and types of glycosylation can account for differences in the ability of CD44 to function as a receptor for hyaluronic acid. We have now used neuraminidase treatment to conclude that sialylation negatively regulates CD44 on the human monocytic cell line THP-1 and peripheral blood monocytes. Both of these cell types displayed increased receptor activity after overnight culture with LPS. Of particular interest, the sialidase inhibitor 2-deoxy-2, 3-dehydro-N-acetylneuraminic acid completely blocked the LPS induced recognition of hyaluronic acid by THP-1 cells. Furthermore, acquisition of this characteristic paralleled induction of one type of sialidase activity. Monocytes may be capable of enzymaticly remodeling cell surface CD44, altering their ability to interact with the extracellular matrix.
Katoh
S
S
Third Department of Internal Medicine, Miyazaki Medical College, Japan. kshigeki@post1.miyazaki-med.ac.jp
Miyagi
T
T
Taniguchi
H
H
Matsubara
Y
Y
Kadota
J
J
Tominaga
A
A
Kincade
P W
PW
Matsukura
S
S
Kohno
S
S
D001386:Azides / Q000494:pharmacology; D001665:Binding Sites / Q000187:drug effects / Q000276:immunology; D002460:Cell Line; D015536:Down-Regulation / Q000276:immunology; D004789:Enzyme Activation / Q000276:immunology; D004790:Enzyme Induction / Q000276:immunology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006031:Glycosylation; D006801:Humans; D018960:Hyaluronan Receptors / Q000378:metabolism*; D006820:Hyaluronic Acid / Q000378:metabolism*; D008070:Lipopolysaccharides / Q000494:pharmacology; D009000:Monocytes / Q000187:drug effects / Q000201:enzymology* / Q000378:metabolism; D009439:Neuraminidase / Q000037:antagonists & inhibitors / Q000096:biosynthesis* / Q000502:physiology; D012794:Sialic Acids / Q000494:pharmacology
D001386:Azides; D004791:Enzyme Inhibitors; D018960:Hyaluronan Receptors; D008070:Lipopolysaccharides; D012794:Sialic Acids; C064632:5-N-acetyl-9-(4-azidosalicoylamido)-2-deoxy-2,3-didehydroneuraminic acid; D006820:Hyaluronic Acid; D009439:Neuraminidase