Related Experiment Videos
Cross-clade CD8(+) T-cell responses with a preference for the predominant circulating clade
Lyle R McKinnon1, T Blake Ball, Joshua Kimani
1Department of Medical Microbiology, University of Manitoba, Winnipeg, Manitoba, Canada.
Journal of Acquired Immune Deficiency Syndromes (1999)
|October 27, 2005
Summary
Human immunodeficiency virus (HIV) genetic diversity challenges vaccine development. However, studies show significant cross-clade immune responses to HIV Env, suggesting potential for broad vaccine efficacy.
Area of Science:
- Immunology
- Virology
- Vaccinology
Background:
- Human immunodeficiency virus (HIV) genetic diversity poses a significant challenge for effective vaccine design.
- Ensuring vaccine-induced protection against diverse HIV strains (inter-clade, intra-clade, recombinant) is critical.
Purpose of the Study:
- To investigate the inter-clade crossreactivity of HIV Env-specific T cell responses in HIV-infected Kenyan populations.
- To understand the implications of HIV genetic diversity on vaccine-induced immunity.
Main Methods:
- Utilized recombinant vaccinia-based interferon gamma (IFN) Elispot assays.
- Tested responses against HIV Env from clades A, B, C, and D in two Kenyan cohorts.
Main Results:
- Observed a substantial proportion of multi-clade T cell responses despite high HIV Env genetic diversity.
- Multi-clade responses showed good correlation, but clade A responses were more frequent and of greater magnitude in some patients.
- Epitope mapping revealed conserved Env regions recognized by CD8(+) T cells, explaining cross-reactivity but not clade A preference.
Conclusions:
- Cross-clade CD8(+) T cell responses to HIV Env are significant, offering hope for broad vaccine applicability.
- Understanding these responses is key to predicting vaccine effectiveness against diverse global HIV epidemics.
- Clade A's distinct immunogenicity warrants further investigation for vaccine strategies.