Graham Simon P, Pellé Roger, Honda Yoshikazu, Mwangi Duncan M, Tonukari Nyerhovwo J, Yamage Mat, Glew E Jane, de Villiers Etienne P, Shah Trushar, Bishop Richard, Abuya Evelyne, Awino Elias, Gachanja James, Luyai Anthony E, Mbwika Ferdinand, Muthiani Anthony M, Ndegwa David M, Njahira Moses, Nyanjui John K, Onono Fredrick O, Osaso Julius, Saya Rosemary M, Wildmann Claude, Fraser Claire M, Maudlin Ian, Gardner Malcolm J, Morzaria Subhash P, Loosmore Sheena, Gilbert Sarah C, Audonnet Jean-Christophe, van der Bruggen Pierre, Nene Vishvanath, Taracha Evans L N
International Livestock Research Institute, Nairobi, Kenya.
Proc Natl Acad Sci U S A. 2006 Feb 28;103(9):3286-91. doi: 10.1073/pnas.0511273103. Epub 2006 Feb 21.
East Coast fever, caused by the tick-borne intracellular apicomplexan parasite Theileria parva, is a highly fatal lymphoproliferative disease of cattle. The pathogenic schizont-induced lymphocyte transformation is a unique cancer-like condition that is reversible with parasite removal. Schizont-infected cell-directed CD8(+) cytotoxic T lymphocytes (CTL) constitute the dominant protective bovine immune response after a single exposure to infection. However, the schizont antigens targeted by T. parva-specific CTL are undefined. Here we show the identification of five candidate vaccine antigens that are the targets of MHC class I-restricted CD8(+) CTL from immune cattle. CD8(+) T cell responses to these antigens were boosted in T. parva-immune cattle resolving a challenge infection and, when used to immunize naïve cattle, induced CTL responses that significantly correlated with survival from a lethal parasite challenge. These data provide a basis for developing a CTL-targeted anti-East Coast fever subunit vaccine. In addition, orthologs of these antigens may be vaccine targets for other apicomplexan parasites.
东海岸热由蜱传播的细胞内顶复门寄生虫小泰氏梨浆虫引起,是一种牛的高度致命性淋巴细胞增生性疾病。致病性裂殖体诱导的淋巴细胞转化是一种独特的类癌状态,在去除寄生虫后可逆转。裂殖体感染细胞导向的CD8(+) 细胞毒性T淋巴细胞(CTL)是单次接触感染后牛的主要保护性免疫反应。然而,小泰氏梨浆虫特异性CTL靶向的裂殖体抗原尚不明确。在此,我们展示了从免疫牛中鉴定出的五种候选疫苗抗原,它们是MHC I类限制性CD8(+) CTL的靶标。在解决攻击感染的小泰氏梨浆虫免疫牛中,对这些抗原的CD8(+) T细胞反应增强,并且当用于免疫未接触过的牛时,诱导的CTL反应与致死性寄生虫攻击后的存活显著相关。这些数据为开发针对CTL的抗东海岸热亚单位疫苗提供了基础。此外,这些抗原的直系同源物可能是其他顶复门寄生虫的疫苗靶标。