Haemaphysalis longicornis is distributed worldwide and transmits a variety of pathogens, causing human and animal disease. Use of chemical acaricides, as a primary tick control method, has several disadvantages, including acaricide resistance, environmental damage and residue accumulation in livestock. Development of a livestock vaccination aimed at a tick protective antigen could be an effective, labor-saving and environmentally-friendly method of reducing tick infestation and transmission of tick-borne pathogens. Lipocalins are low molecular weight proteins that play important roles in blood feeding, immune response and reproduction in ticks. In our study, the open reading frame (ORF) of a lipocalin homologue from H. longicornis (HlLIP) was successfully cloned, which consisted of 387 bp encoding a protein of 128 amino acids. The HlLIP protein sequence showed a close sequence homology with Ixodes persulcatus lipocalin. The HlLIP gene was constitutively detected in all developmental stages and in all tissues of the unfed female tick. The ORF of the HlLIP gene was sub-cloned into pET-32a (+) to obtain the recombinant protein (rHlLIP) and its immunogenicity was comfirmed by western blot. A vaccination trial on rabbits against H. longicornis infestation demonstrated that the rHlLIP protein could significantly prolong the period of tick blood feeding, and reduce tick engorged weight, oviposition and egg hatching rate. The vaccination efficacy of the rHlLIP protein was 60.17 % based on engorged weight, oviposition and egg hatching rate of ticks. The results obtained in this study demonstrate that rHlLIP protein is a promising antigen that could potentially be developed as a vaccine against H. longicornis infestation.

Haemaphysalis longicornis分布于世界各地，传播多种病原体，引起人类和动物疾病。使用化学杀螨剂作为主要的蜱控制方法有几个缺点，包括抗杀螨剂、环境破坏和牲畜残留物积累。开发针对蜱保护性抗原的牲畜疫苗接种可能是一种有效、省力且环保的方法，可以减少蜱感染和蜱传病原体的传播。脂质运载蛋白是低分子量蛋白质，在蜱的血液喂养、免疫反应和繁殖中起着重要作用。在我们的研究中，来自H. longicornis的脂质运载蛋白同系物的开放阅读框 (ORF)(HlLIP) 被成功克隆，由 387 bp 组成，编码 128 个氨基酸的蛋白质。HlLIP 蛋白序列显示出与硬硬蜱脂质运载蛋白的紧密序列同源性。HlLIP 基因在未进食雌性蜱的所有发育阶段和所有组织中均被组成型检测到。将HlLIP基因的ORF亚克隆到pET-32a(+)中获得重组蛋白(rHlLIP)，并通过western blot证实其免疫原性。兔抗长角蚧的疫苗接种试验侵染表明rHlLIP蛋白可以显着延长蜱吸血时间，降低蜱充血量、产卵率和卵孵化率。rHlLIP 蛋白的疫苗接种效力是 60.17%，基于蜱的膨胀重量、产卵和卵孵化率。该研究中获得的结果表明，rHlLIP 蛋白是一种很有前景的抗原，有可能被开发为针对长角嗜血杆菌侵染的疫苗。