Weiss W R, Mellouk S, Houghten R A, Sedegah M, Kumar S, Good M F, Berzofsky J A, Miller L H, Hoffman S L
Infectious Disease Department, Naval Medical Research Institute, Bethesda, Maryland 20814.
J Exp Med. 1990 Mar 1;171(3):763-73. doi: 10.1084/jem.171.3.763.
Irradiated malaria sporozoites can induce CD8+ T cells that are required for protection against infection. However, the parasite antigens targeted by this immune response are unknown. We have discovered a 16-amino acid epitope from the Plasmodium yoelii circumsporozoite (CS) protein that is recognized by cytotoxic T cells from immune mice. Lymphocytes stimulated with this peptide can kill P. yoelii liver stage parasites in vitro in an MHC-restricted, antigen-specific manner. Thus, epitopes from the CS protein are presented on the surface of infected hepatocytes and can be targets for T cells, even though intact CS protein has not been detected on the surface of the infected hepatocyte. A vaccine that induced CTL to parasite antigens might protect humans against malaria by eliminating liver stage parasites.
经辐照的疟原虫子孢子可诱导产生抵御感染所需的CD8+ T细胞。然而,这种免疫反应所靶向的寄生虫抗原尚不清楚。我们从约氏疟原虫环子孢子(CS)蛋白中发现了一个16个氨基酸的表位,该表位可被免疫小鼠的细胞毒性T细胞识别。用此肽刺激的淋巴细胞能够以MHC限制的、抗原特异性的方式在体外杀死约氏疟原虫肝期寄生虫。因此,尽管在受感染肝细胞表面未检测到完整的CS蛋白,但CS蛋白的表位会呈现在受感染肝细胞表面,并且可成为T细胞的靶标。一种能诱导CTL针对寄生虫抗原的疫苗或许可通过清除肝期寄生虫来保护人类免受疟疾侵害。