alpha 1-Acid glycoprotein binds human immunodeficiency virus type 1 (HIV-1) envelope glycoprotein via N-linked glycans.
In the present study, we demonstrate a specific low-affinity interaction between recombinant precursor gp160 (rgp160) or surface unit gp120 (rgp120) of human immunodeficiency virus type 1 (HIV-1) and alpha 1-acid glycoprotein (AGP), a human glycoprotein displaying complex type N-glycans. Binding of rgp160/rgp120 to agarose-coupled AGP was dose-dependent, saturable, calcium-, pH- and temperature-dependent. Binding was inhibited by soluble AGP, asialo-AGP, fetuin, beta-D-GlcNAc47-BSA, alpha-D-Man20-BSA, mannan, complex-type asialo-agalacto-tetraanternary precursor oligosaccharide from human AGP and oligomannose 9 from porcine thyroglobulin; fully deglycosylated AGP was not inhibitory. The three AGP glycoforms separated on immobilized ConA bound rgp160 to the same extent as did unfractionated AGP. These findings extend our previous results on the carbohydrate-binding properties of HIV-1 envelope (Env) glycoprotein in that they demonstrate the involvement of AGP glycan moieties in the binding to rgp160/rgp120. Preincubation of rgp160 with AGP or mannan significantly reduced its binding to monocyte-derived macrophages (MDM), suggesting that AGP may play a role in preventing binding of soluble or virus-bound Env glycoprotein to CD4+ monocytic cells.
Rabehi
L
L
Laboratoire de Biologie Cellulaire, Faculté de Médecine Paris-Nord, Bobigny, France.
Ferriere
F
F
Saffar
L
L
Gattegno
L
L
D001667:Binding, Competitive; D015496:CD4-Positive T-Lymphocytes / Q000378:metabolism / Q000821:virology; D050260:Carbohydrate Metabolism; D002240:Carbohydrate Sequence; D002241:Carbohydrates / Q000737:chemistry; D015699:HIV Envelope Protein gp120 / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D015497:HIV-1 / Q000737:chemistry*; D006801:Humans; D008969:Molecular Sequence Data; D009961:Orosomucoid / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D011994:Recombinant Proteins / Q000378:metabolism; D012685:Sepharose / Q000737:chemistry; D013379:Substrate Specificity
D002241:Carbohydrates; D015699:HIV Envelope Protein gp120; D009961:Orosomucoid; D011994:Recombinant Proteins; D012685:Sepharose