Palanisamy N, Lennerstrand J
Section of Clinical Virology, Department of Medical Sciences, Uppsala University, Uppsala, Sweden.
Scand J Immunol. 2017 May;85(5):350-364. doi: 10.1111/sji.12544.
Usutu virus (family Flaviviridae), once confined to Africa, has emerged in Europe a decade ago. The virus has been spreading throughout Europe at a greater pace mostly affecting avian species. While most bird species remain asymptomatic carriers of this virus, few bird species are highly susceptible. Lately, Usutu virus (USUV) infections in humans were reported sporadically with severe neuroinvasive symptoms like meningoencephalitis. As so much is unknown about this virus, which potentially may cause severe diseases in humans, there is a need for more studies of this virus. In this study, we have used computational tools to predict potential B cell and T cell epitopes of USUV envelope (E) protein. We found that amino acids between positions 68 and 84 could be a potential B cell epitope, while amino acids between positions 53 and 69 could be a potential major histocompatibility complex (MHC) class I- and class II-restricted T cell epitope. By homology 3D modeling of USUV E protein, we found that the predicted B cell epitope was predominantly located in the coil region, while T cell epitope was located in the beta-strand region of the E protein. Additionally, the potential MHC class I T cell epitope (LAEVRSYCYL) was predicted to bind to nearly 24 human leucocyte antigens (HLAs) (IC ≤5000 nm) covering nearly 86.44% of the Black population and 96.90% of the Caucasoid population. Further in vivo studies are needed to validate the predicted epitopes.
乌苏图病毒（黄病毒科）曾一度局限于非洲，十年前在欧洲出现。该病毒一直在欧洲以更快的速度传播，主要影响鸟类物种。虽然大多数鸟类物种仍然是这种病毒的无症状携带者，但很少有鸟类物种高度易感。最近，有零星报道称人类感染乌苏图病毒（USUV）后出现严重的神经侵袭症状，如脑膜脑炎。由于对这种可能在人类中引起严重疾病的病毒了解甚少，因此需要对该病毒进行更多研究。在本研究中，我们使用计算工具预测了USUV包膜（E）蛋白的潜在B细胞和T细胞表位。我们发现，第68至84位之间的氨基酸可能是潜在的B细胞表位，而第53至69位之间的氨基酸可能是潜在的主要组织相容性复合体（MHC）I类和II类限制性T细胞表位。通过对USUV E蛋白进行同源三维建模，我们发现预测的B细胞表位主要位于卷曲区域，而T细胞表位位于E蛋白的β链区域。此外，预测潜在的MHC I类T细胞表位（LAEVRSYCYL）可与近24种人类白细胞抗原（HLA）结合（IC≤5000nm），覆盖近86.44%的黑人人群和96.90%的白种人群。需要进一步的体内研究来验证预测的表位。
