小袋科纤毛虫分类与遗传多态性的研究进展

Advancements in the classification and genetic diversity of Balantidiidae ciliates

摘要:

小袋科纤毛虫是一类广泛寄生于多种无脊椎动物和脊椎动物消化系统的纤毛虫。其中，结肠小袋纤毛虫呈世界性分布，是一种重要的人兽共患病原。长期以来，由于不同宿主来源的小袋科纤毛虫滋养体形态相似，且其形态学特征会受虫体不同生长阶段和宿主肠道微环境的影响而发生变化，导致其分类地位、属级划分及命名在国内外文献中存在分歧与混乱。近年来，小袋科纤毛虫的系统发育关系和遗传多态性研究取得了重要进展，为其分类学重构提供了新的证据。本文在系统梳理国内外研究文献的基础上，结合作者团队的相关研究成果，从形态学特征、成囊能力、宿主特异性及分子系统发育等方面，综述并比较不同宿主源小袋科纤毛虫的分类地位与遗传多态性。基于现有证据，本文支持将小袋科纤毛虫划分为肠袋属(Balantidium)和小袋属(Balantioides)，并明确指出感染人和多种哺乳动物的小袋科纤毛虫应统一归为结肠小袋纤毛虫(Balantioides coli)。这些研究成果和认识有助于澄清小袋科纤毛虫的分类与命名体系，为其生物学特性研究以及人和动物小袋虫病的诊断与防控提供重要参考。

Abstract:

Ciliates of the family Balantidiidae widely parasitize the digestive systems of various invertebrates and vertebrates. Among them, Balantioides coli with cosmopolitan distribution is a major zoonotic pathogen. For a long time, due to the similar morphology of trophozoites of Balantidiidae ciliates from various hosts and the influences of various growing stages and host intestinal microenvironments on morphological characteristics, there have been some inconsistencies and confusions in their classification and nomenclature in literature. Recently, significant progress has been achieved in the study of the phylogenetic relationship and genetic diversity of Balantidiidae ciliates, providing new evidences for their taxonomic reconstruction. On the basis of a systematic review of literature and our findings, this article summarizes the taxonomic status and genetic diversity of Balantidiidae ciliates from different hosts in terms of the morphological characteristics, encystation ability, host specificity, and phylogenetic relationships. The existing evidence supports the division of the family Balantidiidae into two genera Balantidium and Balantioides and indicates that the ciliate infecting humans and various mammals should be classified as Balantioides coli. The related findings and understanding help clarify the taxonomy and nomenclature system of Balantidiidae ciliates and provide an important reference for studying the biological characteristics of Balantidiidae ciliates as well as the diagnosis and control of balantiosis in humans and animals.