Glycosylation patterns of HIV-1 gp120 depend on the type of expressing cells and affect antibody recognition.
Human immunodeficiency virus type 1 (HIV-1) entry is mediated by the interaction between a variably glycosylated envelope glycoprotein (gp120) and host-cell receptors. Approximately half of the molecular mass of gp120 is contributed by N-glycans, which serve as potential epitopes and may shield gp120 from immune recognition. The role of gp120 glycans in the host immune response to HIV-1 has not been comprehensively studied at the molecular level. We developed a new approach to characterize cell-specific gp120 glycosylation, the regulation of glycosylation, and the effect of variable glycosylation on antibody reactivity. A model oligomeric gp120 was expressed in different cell types, including cell lines that represent host-infected cells or cells used to produce gp120 for vaccination purposes. N-Glycosylation of gp120 varied, depending on the cell type used for its expression and the metabolic manipulation during expression. The resultant glycosylation included changes in the ratio of high-mannose to complex N-glycans, terminal decoration, and branching. Differential glycosylation of gp120 affected envelope recognition by polyclonal antibodies from the sera of HIV-1-infected subjects. These results indicate that gp120 glycans contribute to antibody reactivity and should be considered in HIV-1 vaccine design.
Raska
Milan
M
Department of Immunology, Palacky University in Olomouc, Olomouc 77100, Czech Republic. raskamil@uab.edu
Takahashi
Kazuo
K
Czernekova
Lydie
L
Zachova
Katerina
K
Hall
Stacy
S
Moldoveanu
Zina
Z
Elliott
Matt C
MC
Wilson
Landon
L
Brown
Rhubell
R
Jancova
Dagmar
D
Barnes
Stephen
S
Vrbkova
Jana
J
Tomana
Milan
M
Smith
Phillip D
PD
Mestecky
Jiri
J
Renfrow
Matthew B
MB
Novak
Jan
J
D000163:Acquired Immunodeficiency Syndrome / Q000276:immunology; D000906:Antibodies / Q000276:immunology*; D000918:Antibody Specificity; D002460:Cell Line; D045744:Cell Line, Tumor; D018076:DNA, Complementary / Q000235:genetics; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D006026:Glycoside Hydrolases / Q000378:metabolism; D006031:Glycosylation; D015699:HIV Envelope Protein gp120 / Q000235:genetics / Q000276:immunology* / Q000302:isolation & purification / Q000378:metabolism*; D006679:HIV Seropositivity / Q000276:immunology / Q000378:metabolism; D015497:HIV-1 / Q000276:immunology / Q000378:metabolism; D056945:Hep G2 Cells / Q000378:metabolism; D006801:Humans; D019169:Jurkat Cells / Q000378:metabolism; D008358:Mannose / Q000378:metabolism; D037601:Mannose-Binding Lectin / Q000235:genetics; D013058:Mass Spectrometry; D009844:Oligosaccharides / Q000737:chemistry / Q000302:isolation & purification; D010957:Plasmids; D011134:Polysaccharides / Q000737:chemistry / Q000302:isolation & purification
D000906:Antibodies; D018076:DNA, Complementary; D015699:HIV Envelope Protein gp120; D037601:Mannose-Binding Lectin; D009844:Oligosaccharides; D011134:Polysaccharides; C514793:gp120 protein, Human immunodeficiency virus 1; D006026:Glycoside Hydrolases; D008358:Mannose