McKinnon Lyle R, Ball T Blake, Kimani Joshua, Wachihi Charles, Matu Lucy, Luo Ma, Embree Joanne, Fowke Keith R, Plummer Francis A
Department of Medical Microbiology, University of Manitoba, Winnipeg, Manitoba, Canada.
J Acquir Immune Defic Syndr. 2005 Nov 1;40(3):245-9. doi: 10.1097/01.qai.0000184858.16447.04.
Human immunodeficiency virus (HIV) genetic diversity is a major impediment to the design of a successful vaccine. Even if an HIV vaccine is proven effective, it remains to be seen whether this protection will extend to inter-clade, intra-clade, and recombinant strains. We used recombinant vaccinia-based interferon gamma (IFN) Elispot assays to test the inter-clade crossreactivity of clades A, B, C, and D HIV Env in two cohorts of HIV-infected Kenyans. Despite the tremendous diversity in this HIV protein, a substantial proportion of multi-clade responses were observed. Although these multi-clade responses correlated well with each other in regression analyses, clade A responses were seen at a higher frequency and at greater relative magnitudes in a proportion of these patients, when compared to the other three clades. Epitope mapping indicates CD8(+) T cell recognition of conserved regions of Env, accounting for the high degree of cross-reactivity but not the clade A preference. A better understanding of cross-clade CD8(+) T cell responses to HIV may help to predict whether a successful vaccine could be used to stop geographically and genetically distinct HIV epidemics.
人类免疫缺陷病毒（HIV）的基因多样性是成功设计疫苗的主要障碍。即便一种HIV疫苗被证明有效，这种保护作用是否能扩展到不同分支、同一分支内以及重组毒株仍有待观察。我们使用基于重组痘苗病毒的干扰素γ（IFN）酶联免疫斑点分析，在两组感染HIV的肯尼亚人群中检测了A、B、C和D组HIV包膜蛋白（Env）的分支间交叉反应性。尽管这种HIV蛋白具有极大的多样性，但仍观察到相当比例的多分支反应。虽然在回归分析中这些多分支反应之间相关性良好，但与其他三个分支相比，在部分患者中A组反应出现的频率更高，相对强度也更大。表位作图表明CD8(+) T细胞识别Env的保守区域，这解释了高度的交叉反应性，但无法解释对A组的偏好。更好地理解跨分支CD8(+) T细胞对HIV的反应，可能有助于预测一种成功的疫苗是否可用于阻止地理和基因上不同的HIV流行。
