Immunodominance of HIV-1 specific CD8+ T-cell responses is related to disease progression rate in vertically infected adolescents

PLoS One. 2011;6(7):e21135. doi: 10.1371/journal.pone.0021135. Epub 2011 Jul 19.

Abstract

Background: HIV-1 vertically infected children in the USA are living into adolescence and beyond with the widespread use of antiretroviral drugs. These patients exhibit striking differences in the rate of HIV-1 disease progression which could provide insights into mechanisms of control. We hypothesized that differences in the pattern of immunodomination including breadth, magnitude and polyfunctionality of HIV-1 specific CD8+ T cell response could partially explain differences in progression rate.

Methodology/principal findings: In this study, we mapped, quantified, and assessed the functionality of these responses against individual HIV-1 Gag peptides in 58 HIV-1 vertically infected adolescents. Subjects were divided into two groups depending upon the rate of disease progression: adolescents with a sustained CD4%≥25 were categorized as having no immune suppression (NS), and those with CD4%≤15 categorized as having severe immune suppression (SS). We observed differences in the area of HIV-1-Gag to which the two groups made responses. In addition, subjects who expressed the HLA- B*57 or B*42 alleles were highly likely to restrict their immunodominant response through these alleles. There was a significantly higher frequency of naïve CD8+ T cells in the NS subjects (p = 0.0066) compared to the SS subjects. In contrast, there were no statistically significant differences in any other CD8+ T cell subsets. The differentiation profiles and multifunctionality of Gag-specific CD8+ T cells, regardless of immunodominance, also failed to demonstrate meaningful differences between the two groups.

Conclusions/significance: Together, these data suggest that, at least in vertically infected adolescents, the region of HIV-1-Gag targeted by CD8+ T cells and the magnitude of that response relative to other responses may have more importance on the rate of disease progression than their qualitative effector functions.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Adolescent
  • Alleles
  • Amino Acid Sequence
  • CD8-Positive T-Lymphocytes / immunology*
  • CD8-Positive T-Lymphocytes / pathology
  • CD8-Positive T-Lymphocytes / physiology
  • Cell Degranulation
  • Cell Differentiation / immunology
  • Cohort Studies
  • Cytokines / metabolism
  • Disease Progression*
  • Female
  • HIV Infections / immunology*
  • HIV Infections / virology*
  • HIV-1 / immunology*
  • HLA Antigens / immunology
  • Humans
  • Immunodominant Epitopes / immunology*
  • Infectious Disease Transmission, Vertical*
  • Male
  • Molecular Sequence Data
  • Peptides / chemistry
  • Peptides / immunology
  • Species Specificity
  • gag Gene Products, Human Immunodeficiency Virus / immunology

Substances

  • Cytokines
  • HLA Antigens
  • Immunodominant Epitopes
  • Peptides
  • gag Gene Products, Human Immunodeficiency Virus