Lewinsohn D M, Briden A L, Reed S G, Grabstein K H, Alderson M R
Division of Pulmonary and Critical Care Medicine, Oregon Health Sciences, University/Portland Veterans Affairs Medical Center, Portland, OR 97201, USA.
J Immunol. 2000 Jul 15;165(2):925-30. doi: 10.4049/jimmunol.165.2.925.
Previous studies in mice and humans models have suggested an important role for CD8+ T cells in host defense to Mycobacterium tuberculosis (Mtb). In humans, CD8+ Mtb-reactive T cells have been described that are HLA-A2-, B52-, as well as CD1-restricted. Recently, we have described Mtb-specific CD8+ T cells that are neither HLA-A-, B-, or C- nor group 1 CD1-restricted. At present, little is known about the relative contribution of each of these restriction specificities to the overall CD8+ response to Mtb. An IFN-gamma enzyme-linked immunospot assay was used to determine the frequency of Mtb-reactive CD8+ T cells directly from PBMC. The effector cell frequency among five healthy purified protein derivative-positive subjects was 1/7,600 +/- 4,300 compared with 1/16,000 +/- 7,000 in six purified protein derivative-negative controls. To determine the frequencies of classically, CD1-, and nonclassically restricted cells, a limiting dilution analysis was performed. In one purified protein derivative-positive subject, 192 clones were generated using Mtb-infected dendritic cells (DC). Clones were assessed for reactivity against control autologous DC, Mtb-infected autologous DC, and HLA-mismatched CD1+ targets (DC), as well as HLA-mismatched CD1- targets (macrophages). Of the 96 Mtb-reactive CD8+ T cell clones, four (4%) were classically restricted and 92 (96%) were nonclassically restricted. CD1-restricted cells were not detected. Of the classically restricted cells, two were HLA-B44 restricted and one was HLA-B14 restricted. These results suggest that while classically restricted CD8+ lymphocytes can be detected, they comprise a relatively small component of the overall CD8+ T cell response to Mtb. Further definition of the nonclassical response may aid development of an effective vaccine against tuberculosis.
先前在小鼠和人类模型中的研究表明，CD8 + T细胞在宿主防御结核分枝杆菌（Mtb）中发挥重要作用。在人类中，已描述了HLA - A2 -、B52 -以及受CD1限制的CD8 + Mtb反应性T细胞。最近，我们描述了既不受HLA - A -、B -或C限制，也不受1类CD1限制的Mtb特异性CD8 + T细胞。目前，对于这些限制特异性中的每一种对整体CD8 + 对Mtb反应的相对贡献知之甚少。使用干扰素 - γ酶联免疫斑点测定法直接从外周血单核细胞（PBMC）中确定Mtb反应性CD8 + T细胞的频率。五名健康的纯化蛋白衍生物阳性受试者中的效应细胞频率为1/7,600±4,300，而六名纯化蛋白衍生物阴性对照中的频率为1/16,000±7,000。为了确定经典限制、CD1限制和非经典限制细胞的频率，进行了有限稀释分析。在一名纯化蛋白衍生物阳性受试者中，使用Mtb感染的树突状细胞（DC）产生了192个克隆。评估克隆对对照自体DC、Mtb感染的自体DC以及HLA不匹配的CD1 + 靶标（DC）和HLA不匹配的CD1 - 靶标（巨噬细胞）的反应性。在96个Mtb反应性CD8 + T细胞克隆中，四个（4%）是经典限制的，92个（96%）是非经典限制的。未检测到CD1限制的细胞。在经典限制的细胞中，两个受HLA - B44限制，一个受HLA - B14限制。这些结果表明，虽然可以检测到经典限制的CD8 + 淋巴细胞，但它们在整体CD8 + T细胞对Mtb的反应中占相对较小的部分。对非经典反应的进一步定义可能有助于开发有效的抗结核疫苗。
