Keating Sheila M, Bollinger Robert C, Quinn Thomas C, Jackson J Brooks, Carruth Lucy M
Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA.
AIDS Res Hum Retroviruses. 2002 Sep 20;18(14):1067-79. doi: 10.1089/08892220260235425.
Identifying immunodominant regions of HIV-1 that are recognized by CD8(+) T lymphocytes in infected individuals may be important for the design and evaluation of candidate HIV-1 vaccines, particularly for developing countries. In this study, cryopreserved peripheral blood mononuclear cells (PBMCs) from 15 chronically HIV-1-infected U.S. volunteers were screened for HIV-1 Gag-specific T lymphocyte interferon gamma production in an enzyme-linked immunospot (ELISpot) assay matrix format, using overlapping HIV-1 subtype A, B, and C Gag peptide pools. In the initial matrix screen, responses to HIV-1 subtype B Gag were detected in 11 of 15 (73%) of seropositive individuals and in none of 4 HIV-1-seronegative controls. There were differences in both the breadth and magnitudes of the responses observed in the matrix assay. Responses varied in breadth, ranging from broad responses (more than four peptides) of moderate magnitude (<100 spot-forming cells [SFCs]/10(5) PBMCs) to narrowly focused (two or fewer peptides), more potent responses (>150 SFC/10(5) PBMCs). Responses to A, B, and C clade peptides of HIV-1 Gag revealed that all responders to subtype B peptides were also found to recognize corresponding peptides from at least one of the other clades. The ability to recognize cross-clade peptides with one or two amino acid substitutions relative to the B clade peptide was both peptide and patient dependent. Overall, our results show that the ELISpot matrix algorithm described here may be an efficient approach for characterizing cross-clade CD8(+) T cell responses in either seropositive individuals or in seronegative HIV-1 vaccine recipients.
识别受感染个体中被CD8(+) T淋巴细胞识别的HIV-1免疫显性区域，对于候选HIV-1疫苗的设计和评估可能至关重要，特别是对发展中国家而言。在本研究中，使用重叠的HIV-1 A、B和C亚型Gag肽池，以酶联免疫斑点（ELISpot）分析矩阵形式，对来自15名慢性HIV-1感染的美国志愿者的冷冻保存外周血单核细胞（PBMC）进行HIV-1 Gag特异性T淋巴细胞干扰素γ产生的筛选。在初始矩阵筛选中，15名血清阳性个体中的11名（73%）检测到对HIV-1 B亚型Gag的反应，而4名HIV-1血清阴性对照中均未检测到。在矩阵分析中观察到的反应广度和强度均存在差异。反应广度各不相同，从适度强度（<100个斑点形成细胞[SFCs]/10(5) PBMCs）的广泛反应（超过四个肽段）到狭窄聚焦（两个或更少肽段）、更强效的反应（>150 SFC/10(5) PBMCs）。对HIV-1 Gag的A、B和C亚型肽段的反应表明，所有对B亚型肽段有反应的个体也被发现能识别来自至少一个其他亚型的相应肽段。识别相对于B亚型肽段有一两个氨基酸替换的跨亚型肽段的能力既取决于肽段也取决于患者。总体而言，我们的结果表明，此处描述的ELISpot矩阵算法可能是一种有效方法，用于表征血清阳性个体或HIV-1血清阴性疫苗接种者中的跨亚型CD8(+) T细胞反应。
