Zhang Song-Bo, Gao Zhi-Hua, Wang Yi-Kui, Lv Wen-Xia, Dong Ke-Xin, Guo Fei-Di, Wang Run-Ying, Yang Xiao-Long
Hebei Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology, Hebei Collaborative Innovation Center for Eco-Environment, Ministry of Education Key Laboratory of Molecular and Cellular Biology, College of Life Sciences, Hebei Normal University, Shijiazhuang, China.
Pest Manag Sci. 2024 Aug;80(8):3957-3966. doi: 10.1002/ps.8099. Epub 2024 Apr 8.
Ticks, which are obligate blood-feeding parasites, transmit a wide range of pathogens during their hematophagic process. Certain enzymes and macromolecules play a crucial role in inhibition of several tick physiological processes, including digestion and reproduction. In the present study, genes encoding type 2 cystatin were cloned and characterized from Haemaphysalis doenitzi, and the potential role of cystatin in tick control was further assessed.
Two cystatin genes, HDcyst-1 and HDcyst-2, were successfully cloned from the tick H. doenitzi. Their open reading frames are 390 and 426 base pairs, and the number of coding amino acids are 129 and 141, respectively. In the midgut, salivary glands, Malpighian tubules and ovaries of ticks, the relative expression of HDcyst-1 was higher in the midgut and Malpighian tubules, and HDcyst-2 was higher in the salivary glands of H. doenitzi, respectively. Lipopolysaccharide (LPS) injection and low-temperature stress elevated cystatin expression in ticks. Enzyme-linked immunosorbent assay showed that both rHDcyst-1 and rHDcyst-2 protein vaccines increased antibody levels in immunized rabbits. A vaccination trial in rabbits infected with H. doenitzi showed that both recombinant cystatin proteins significantly reduced tick engorgement weights and egg mass weight, in particular, rHDcyst-1 significantly prolonged tick engorgement time by 1 day and reduced egg hatching rates by 16.9%. In total, rHDcyst-1 and rHDcyst-2 protein vaccinations provided 64.1% and 51.8% protection to adult female ticks, respectively.
This is the first report on the immunological characterization of the cystatin protein and sequencing of the cystatin gene in H. doenitzi. Cystatin proteins are promising antigens that have the potential to be used as vaccines for infestation of H. doenitzi control. © 2024 Society of Chemical Industry.
蜱作为专性吸血寄生虫，在其吸血过程中传播多种病原体。某些酶和大分子在抑制蜱的多种生理过程（包括消化和繁殖）中起着关键作用。在本研究中，从花蜱中克隆并鉴定了编码2型半胱氨酸蛋白酶抑制剂的基因，并进一步评估了半胱氨酸蛋白酶抑制剂在蜱虫防治中的潜在作用。
成功从花蜱中克隆出两个半胱氨酸蛋白酶抑制剂基因HDcyst-1和HDcyst-2。它们的开放阅读框分别为390和426个碱基对，编码的氨基酸数量分别为129和141个。在蜱的中肠、唾液腺、马氏管和卵巢中，HDcyst-1在中肠和马氏管中的相对表达较高，而HDcyst-2在花蜱的唾液腺中表达较高。注射脂多糖（LPS）和低温胁迫可提高蜱体内半胱氨酸蛋白酶抑制剂的表达。酶联免疫吸附测定表明，rHDcyst-1和rHDcyst-2蛋白疫苗均可提高免疫兔的抗体水平。对感染花蜱的家兔进行的疫苗接种试验表明，两种重组半胱氨酸蛋白酶抑制剂蛋白均显著降低了蜱的饱血体重和卵块重量，特别是rHDcyst-1显著延长了蜱的饱血时间1天，并使卵孵化率降低了16.9%。总体而言，rHDcyst-1和rHDcyst-2蛋白疫苗分别为成年雌蜱提供了64.1%和51.8% 的保护。
这是关于花蜱中半胱氨酸蛋白酶抑制剂蛋白的免疫学特性和半胱氨酸蛋白酶抑制剂基因测序的首次报道。半胱氨酸蛋白酶抑制剂蛋白是有前景的抗原，有潜力用作防治花蜱感染的疫苗。© 2024化学工业协会
