Carbohydrate on human factor VIII/von Willebrand factor. Impairment of function by removal of specific galactose residues.
Journal Article
Human factor VIII/von Willebrand factor protein containing 120 +/- 12 nmol of sialic acid and 135 +/- 13 nmol of galactose/mg of protein was digested with neuraminidase. The affinity of native factor VIII/von Willebrand factor and its asialo form for the hepatic lectin that specifically binds asialoglycoproteins was assessed from in vitro binding experiments. Native factor VIII/von Willebrand factor exhibited negligible affinity while binding of the asialo derivative was comparable to that observed for asialo-alpha1-acid glycoprotein. Incubation of asialo-factor VIII/von Willebrand factor with Streptococcus pneumoniae beta-galactosidase removed only 62% of the galactose but abolished binding to the purified hepatic lectin. When the asialo derivative was incubated with purified beta-D-galactoside alpha2 leads to 6 sialyltransferase and CMP-[14C]NeuAc, only 61% of the galactose incorporated [14C]NeuAc. From the known specificites of these enzymes, it is concluded that galactose residues important in lectin binding are present in a terminal Gal/beta1 leads to 4GlcNAc sequence on asialo-factor VIII/von Willebrand factor. The relative ristocetin-induced platelet aggregating activity of native, asialo-, and agalacto-factor VIII/von Willebrand factor was 100:38:12, respectively, while procoagulant activity was 100:100:103.
Full Text
Duke Authors
Cited Authors
- Sodetz, JM; Paulson, JC; Pizzo, SV; McKee, PA
Published Date
- October 25, 1978
Published In
Volume / Issue
- 253 / 20
Start / End Page
- 7202 - 7206
PubMed ID
- 100492
Pubmed Central ID
- 100492
International Standard Serial Number (ISSN)
- 0021-9258
Language
- eng
Conference Location
- United States