Increased Levels of Galactose-Deficient IgG in Sera of HIV-1-infected Individuals

AIDS. 2005 Mar 4;19(4):381-9. doi: 10.1097/01.aids.0000161767.21405.68.

Abstract

Background: The IgG from sera of patients with chronic inflammatory diseases of autoimmune character or some chronic microbial infections is frequently deficient in galactose on N-linked glycans. However, this phenomenon has not been investigated at length in human viral infections.

Objectives: To evaluate the glycosylation of serum IgG in HIV-1-positive patients.

Methods: Psathyrella velutina lectin was used in enzyme-linked immunosorbent and Western blot assays to determine glycosylation. In addition, gas-liquid chromatography and mass spectrometry were utilized to confirm the galactose deficiency observed in the lectin-binding assays.

Results: HIV-1-infected individuals had significantly higher levels of galactose-deficient IgG than healthy controls. In fact, the galactose deficiency of the N-linked glycans observed in other diseases was even more profound in HIV-1 infection. This deficiency was primarily restricted to IgG when total serum glycoproteins were evaluated and IgG1 was the subclass most affected in all patients. Also, a significant increase in lectin binding was observed on IgG2 and IgG4 from HIV-1-positive females compared with HIV-1-negative females.

Conclusions: Identification of deficient galactosylation of serum IgG from HIV-1-infected patients extended the spectrum of diseases in which this phenomenon has been observed. In addition, the results suggest yet another aspect of immune dysfunction as a result of HIV-1 infection.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • Agaricales
  • Blotting, Western
  • Enzyme-Linked Immunosorbent Assay / methods
  • Female
  • Galactose / blood
  • Galactose / deficiency*
  • Glycosylation
  • HIV Infections / blood*
  • HIV Infections / immunology
  • HIV-1*
  • Humans
  • Immunoglobulin G / blood*
  • Immunoglobulin Isotypes / blood
  • Lectins / metabolism
  • Male
  • Middle Aged

Substances

  • Immunoglobulin G
  • Immunoglobulin Isotypes
  • Lectins
  • Galactose