Research Center for Parasites & Vectors (RCPV), College of Veterinary Medicine, Hunan Agricultural University, Changsha, 410128, China.
Parasit Vectors. 2022 May 24;15(1):179. doi: 10.1186/s13071-022-05287-7.
Tick hemolymph bathes internal organs, acts as an exchange medium for nutrients and cellular metabolites, and offers protection against pathogens. Hemolymph is abundant in proteins. However, there has been limited integrated protein analysis in tick hemolymph thus far. Moreover, there are difficulties in differentiating tick-derived proteins from the host source. The aim of this study was to profile the tick/host protein components in the hemolymph of Haemaphysalis flava.
Hemolymph from adult engorged H. flava females was collected by leg amputation from the Erinaceus europaeus host. Hemolymph proteins were extracted by a filter-aided sample preparation protocol, digested by trypsin, and assayed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). MS raw data were searched against the UniProt Erinaceidae database and H. flava protein database for host- and tick-derived protein identification. Protein abundance was further quantified by intensity-based absolute quantification (iBAQ).
Proteins extracted from hemolymph unevenly varied in size with intense bands between 100 and 130 kDa. In total, 312 proteins were identified in the present study. Therein 40 proteins were identified to be host-derived proteins, of which 18 were high-confidence proteins. Top 10 abundant host-derived proteins included hemoglobin subunit-α and subunit-β, albumin, serotransferrin-like, ubiquitin-like, haptoglobin, α-1-antitrypsin-like protein, histone H2B, apolipoprotein A-I, and C3-β. In contrast, 169 were high-confidence tick-derived proteins. These proteins were classified into six categories based on reported functions in ticks, i.e., enzymes, enzyme inhibitors, transporters, immune-related proteins, muscle proteins, and heat shock proteins. The abundance of Vg, microplusin and α-2-macroglobulin was the highest among tick-derived proteins as indicated by iBAQ.
Numerous tick- and host-derived proteins were identified in hemolymph. The protein profile of H. flava hemolymph revealed a sophisticated protein system in the physiological processes of anticoagulation, digestion of blood meal, and innate immunity. More investigations are needed to characterize tick-derived proteins in hemolymph.
蜱的血淋巴浸润内部器官，充当营养物质和细胞代谢物的交换介质，并提供针对病原体的保护。血淋巴富含蛋白质。然而，迄今为止，对蜱的血淋巴中的综合蛋白质分析还很有限。此外，从宿主来源中区分蜱衍生的蛋白质存在困难。本研究的目的是分析黄足硬蜱血淋巴中的蜱/宿主蛋白质成分。
通过从宿主欧洲刺猬的腿上截肢来收集成年饱血黄足硬蜱雌性的血淋巴。通过过滤辅助样品制备方案提取血淋巴蛋白，用胰蛋白酶消化，并通过液相色谱-串联质谱（LC-MS/MS）进行分析。MS 原始数据与 UniProt 刺猬科数据库和黄足硬蜱蛋白质数据库进行搜索，以鉴定宿主和蜱衍生的蛋白质。蛋白质丰度通过基于强度的绝对定量（iBAQ）进一步定量。
从血淋巴中提取的蛋白质大小不均匀，大小在 100-130 kDa 之间的条带强烈。本研究共鉴定出 312 种蛋白质。其中 40 种蛋白质被鉴定为宿主衍生蛋白，其中 18 种为高置信蛋白。前 10 种丰富的宿主衍生蛋白包括血红蛋白亚基-α和亚基-β、白蛋白、血清转铁蛋白样蛋白、泛素样蛋白、触珠蛋白、α-1-抗胰蛋白酶样蛋白、组蛋白 H2B、载脂蛋白 A-I 和 C3-β。相比之下，有 169 种是高置信度的蜱衍生蛋白。这些蛋白质根据在蜱中的报道功能分为六类，即酶、酶抑制剂、转运蛋白、免疫相关蛋白、肌肉蛋白和热休克蛋白。根据 iBAQ，Vg、microplusin 和 α-2-巨球蛋白的丰度是蜱衍生蛋白中最高的。
在血淋巴中鉴定出许多蜱和宿主衍生的蛋白质。黄足硬蜱血淋巴的蛋白质谱揭示了一个复杂的蛋白质系统，参与抗凝、血液消化和先天免疫等生理过程。需要进一步研究来表征血淋巴中的蜱衍生蛋白。
