Dieli F, Troye-Blomberg M, Farouk S E, Sireci G, Salerno A
Department of Biopathology, University of Palermo, Italy.
Curr Mol Med. 2001 Sep;1(4):437-46. doi: 10.2174/1566524013363627.
Tuberculosis and malaria remain the leading causes of mortality among human infectious diseases in the world. It is estimated that 3 to 5 million people die from tuberculosis and malaria each year. Although it is traditionally believed that CD4 and CD8 alphabeta T lymphocytes are mandatory for protective immune responses against Mycobacterium tuberculosis and Plasmodium falciparum (the ethiologic agents of tuberculosis and the most severe form of malaria, respectively), there is still incomplete understanding of the mechanisms of immune protection and of the causes of its failure in the affected patients. Several studies in humans and animal models have suggested that Vgamma9/Vdelta2 T cells may play an important role in the immune responses against Mycobacterium tuberculosis and Plasmodium falciparum. Vgamma9/Vdelta2 T cells represent about 75% of all circulating gammadelta T cells while they can be greatly expanded during the acute phase of Mycobacterium tuberculosis and Plasmodium falciparum malaria. Vgamma9/Vdelta2 T recognize a new class of antigenic molecules which are nonpeptidic in nature and contain critical phosphate moieties (phosphoantigens). Interestingly, phosphoantigens isolated from Mycobacterium tuberculosis and Plasmodium falciparum share strong structural homology and are probably identical. However, despite a large body of data reported in the literature, it is not yet clear whether Vgamma9/Vdelta2 T cells play a protective or pathogenic role in immune responses against Mycobacterium tuberculosis and Plasmodium falciparum. In this review we summarize our current knowledge of the biology of Vgamma9/Vdelta2 T cells in response to the two pathogens, Mycobacterium tuberculosis and Plasmodium falciparum, and provide evidence suggesting definition of a novel and important protective role through which Vgamma9/Vdelta2 T cells can contribute to the killing of microorganisms residing in intracellular compartments.
结核病和疟疾仍然是全球人类传染病致死的主要原因。据估计，每年有300万至500万人死于结核病和疟疾。传统观点认为，CD4和CD8αβ T淋巴细胞对于针对结核分枝杆菌和恶性疟原虫（分别为结核病和最严重形式疟疾的病原体）的保护性免疫反应至关重要，但目前对于免疫保护机制及其在受影响患者中失效的原因仍未完全了解。多项针对人类和动物模型的研究表明，Vγ9/Vδ2 T细胞可能在针对结核分枝杆菌和恶性疟原虫的免疫反应中发挥重要作用。Vγ9/Vδ2 T细胞约占所有循环γδ T细胞的75%，在结核分枝杆菌和恶性疟原虫疟疾的急性期它们可大量扩增。Vγ9/Vδ2 T细胞识别一类新型抗原分子，这类分子本质上是非肽性的且含有关键的磷酸基团（磷酸抗原）。有趣的是，从结核分枝杆菌和恶性疟原虫中分离出的磷酸抗原具有很强的结构同源性，可能是相同的。然而，尽管文献中报道了大量数据，但尚不清楚Vγ9/Vδ2 T细胞在针对结核分枝杆菌和恶性疟原虫的免疫反应中是发挥保护作用还是致病作用。在这篇综述中，我们总结了目前关于Vγ9/Vδ2 T细胞对结核分枝杆菌和恶性疟原虫这两种病原体反应的生物学知识，并提供证据表明其可定义一种新的重要保护作用，通过这种作用Vγ9/Vδ2 T细胞可有助于杀灭存在于细胞内区室的微生物。
