Protective Effect of Interleukin‐4 −589T Polymorphism on Human Immunodeficiency Virus Type 1 Disease Progression: Relationship with Virus Load

Abstract

The interleukin (IL)-4 -589T allele bears a single nucleotide polymorphism at position -589 upstream from the open-reading frame of the IL-4 gene. To determine the influence of this allele on human immunodeficiency virus (HIV) type 1 disease, disease progression and serum virus load were assessed by IL-4 genotype in 427 white patients with known seroconversion dates who were followed in the French SEROCO cohort between 1988 and 1996. Serum virus load was 0.20 log lower during the 6–24-month plateau phase after seroconversion in patients with IL-4 -589T than in those without this allele (P = .02). Kaplan-Meier analysis survival curves showed a slower progression to clinical AIDS in carriers of IL-4 -589T (P = .04). Adjustment for early serum virus load greatly diminished the strength of this association. These results suggest that IL-4 -589T protects against HIV-1 disease progression by reducing virus load.