Chatanga Elisha, Hayashida Kyoko, Muleya Walter, Kusakisako Kodai, Moustafa Mohamed Abdallah Mohamed, Salim Bashir, Katakura Ken, Sugimoto Chihiro, Nonaka Nariaki, Nakao Ryo
Laboratory of Parasitology, Graduate School of Infectious Diseases, Faculty of Veterinary Medicine, Hokkaido University, Kita-18, Nishi-9, Sapporo, Hokkaido 060-0818, Japan.
Department of Veterinary Medicine, Lilongwe University of Agriculture and Natural Resources, P.O. Box 219, Lilongwe, Malawi.
Pathogens. 2020 Apr 30;9(5):334. doi: 10.3390/pathogens9050334.
East Coast fever (ECF) is an acute fatal tick-borne disease of cattle caused by . It causes major losses in exotic and crossbreed cattle, but this could be prevented by a vaccine of if the vaccine is selected properly based on information from molecular epidemiology studies. The Muguga cocktail (MC) vaccine (Muguga, Kiambu 5 and Serengeti-transformed strains) has been used on exotic and crossbreed cattle. A total of 254 samples from vaccinated and unvaccinated cattle were used to understand the genetic diversity of in Malawi using partial sequences of the Tp1 and Tp2 genes encoding CD8 antigens, known to be immunodominant and current candidate antigens for a subunit vaccine. Single nucleotide polymorphisms were observed at 14 positions (3.65%) in Tp1 and 156 positions (33.12%) in Tp2, plus short deletions in Tp1, resulting in 6 and 10 amino acid variants in the Tp1 and Tp2 genes, respectively. Most sequences were either identical or similar to Muguga and Kiambu 5 strains. This may suggest the possible expansion of vaccine components into unvaccinated cattle, or that a very similar genotype already existed in Malawi. This study provides information that support the use of MC to control ECF in Malawi.
东海岸热（ECF）是一种由蜱传播的牛急性致命疾病。它给外来品种和杂交牛造成了重大损失，但如果根据分子流行病学研究信息正确选择疫苗，一种疫苗可以预防这种疾病。穆古加混合疫苗（MC）（穆古加、基安布5和塞伦盖蒂转化株）已用于外来品种和杂交牛。利用编码CD8抗原的Tp1和Tp2基因的部分序列，从接种疫苗和未接种疫苗的牛身上共采集了254个样本，以了解马拉维的遗传多样性，已知这些抗原具有免疫优势，是亚单位疫苗的当前候选抗原。在Tp1的14个位置（3.65%）和Tp2的156个位置（33.12%）观察到单核苷酸多态性，加上Tp1中的短缺失，分别导致Tp1和Tp2基因中出现6个和10个氨基酸变体。大多数序列与穆古加和基安布5菌株相同或相似。这可能表明疫苗成分可能已扩展到未接种疫苗的牛中，或者马拉维已经存在非常相似的基因型。这项研究提供了支持在马拉维使用MC控制ECF的信息。
