Institute of Inorganic and Analytical Chemistry, Justus Liebig University Giessen, Giessen, Germany.
Institute of Parasitology, Justus Liebig University Giessen, Biomedical Research Center Seltersberg (BFS), Giessen, Germany.
PLoS Negl Trop Dis. 2020 May 13;14(5):e0008145. doi: 10.1371/journal.pntd.0008145. eCollection 2020 May.
Schistosomes are human pathogens causing the neglected tropical disease schistosomiasis, which occurs worldwide in (sub-)tropical regions. This infectious disease is often associated with poverty, and more than 700 million people are at risk of infection. Exploitation of novel habitats and limited therapeutic options brought schistosomes into research focus. Schistosomes are the only trematodes that have evolved separate sexes. They are covered by their metabolically active tegument, a surface area representing the interface between male and female in their permanent mating contact but also between parasite and host. The tegument comprises, besides others, numerous specific lipid compounds. Limited information is available on the exact lipid composition and its spatial distribution. We used atmospheric-pressure scanning microprobe matrix-assisted laser desorption/ionization (AP-SMALDI) mass spectrometry imaging (MSI) to characterize the Schistosoma mansoni tegument surface in comparison to tissue sections of whole worms or couples. We found that phosphatidylcholines (PC) and specific phosphatidylethanolamines (PE) are significantly more abundant inside the worm body compared to the tegument. On the other hand, the latter was found to be enriched in sphingomyelins (SM), phosphatidylserines (PS), lysophosphatidylcholines (LPC), and specific PE species. We further investigated lipid classes concerning number of carbon atoms in fatty acyl chains as well as the degree of unsaturation and found pronounced differences between the tegument and whole-worm body. Furthermore, differences between male and female teguments were found. The lipid composition of S. mansoni tissues has been investigated in an untargeted, spatially resolved manner for the first time.
血吸虫是一种引起被忽视的热带病——血吸虫病的人类病原体，该病在全球（亚热带）热带地区流行。这种传染病常常与贫困有关，有超过 7 亿人面临感染风险。由于新栖息地的开发和有限的治疗选择，血吸虫成为了研究的焦点。血吸虫是唯一进化出雌雄异体的吸虫。它们被代谢活跃的表皮所覆盖，这一表面区域代表了它们在永久性交配接触中雌雄之间的界面，也代表了寄生虫和宿主之间的界面。表皮除其他物质外，还包含许多特定的脂质化合物。关于确切的脂质组成及其空间分布，目前的信息有限。我们使用常压扫描微探针基质辅助激光解吸/电离（AP-SMALDI）质谱成像（MSI）技术，对曼氏血吸虫表皮表面进行了特征分析，与整个蠕虫或配对体的组织切片进行了比较。我们发现，与表皮相比，磷脂酰胆碱（PC）和特定的磷脂酰乙醇胺（PE）在蠕虫体内的含量明显更高。另一方面，后者被发现富含鞘磷脂（SM）、磷脂酰丝氨酸（PS）、溶血磷脂酰胆碱（LPC）和特定的 PE 物质。我们进一步研究了有关脂肪酸链碳原子数量以及不饱和程度的脂质类别，发现表皮和整个蠕虫体之间存在明显差异。此外，还发现了雌雄表皮之间的差异。首次以非靶向、空间分辨的方式研究了曼氏血吸虫组织的脂质组成。
