Department of Microbiology, Immunology, and Molecular Genetics, University of California Los Angeles, Los Angeles, California, United States of America.
PLoS Pathog. 2010 Jan 29;6(1):e1000739. doi: 10.1371/journal.ppat.1000739.
African trypanosomes are devastating human and animal pathogens that cause significant human mortality and limit economic development in sub-Saharan Africa. Studies of trypanosome biology generally consider these protozoan parasites as individual cells in suspension cultures or in animal models of infection. Here we report that the procyclic form of the African trypanosome Trypanosoma brucei engages in social behavior when cultivated on semisolid agarose surfaces. This behavior is characterized by trypanosomes assembling into multicellular communities that engage in polarized migrations across the agarose surface and cooperate to divert their movements in response to external signals. These cooperative movements are flagellum-mediated, since they do not occur in trypanin knockdown parasites that lack normal flagellum motility. We term this behavior social motility based on features shared with social motility and other types of surface-induced social behavior in bacteria. Social motility represents a novel and unexpected aspect of trypanosome biology and offers new paradigms for considering host-parasite interactions.
非洲锥虫是一种具有破坏性的人类和动物病原体，会导致大量人类死亡，并限制撒哈拉以南非洲的经济发展。对锥虫生物学的研究通常将这些原生动物寄生虫视为悬浮培养或动物感染模型中的单个细胞。在这里，我们报告说，当在半固体琼脂表面上培养时，非洲锥虫布氏锥虫的前鞭毛体形式会表现出社会行为。这种行为的特征是锥虫组装成多细胞群落，在琼脂表面上进行极化迁移，并合作响应外部信号改变它们的运动。这些合作运动是鞭毛介导的，因为它们不会发生在缺乏正常鞭毛运动的 trypanin 敲低寄生虫中。我们将这种行为称为社交运动，因为它与细菌中的社交运动和其他类型的表面诱导的社交行为具有共同特征。社交运动代表了锥虫生物学的一个新的和意想不到的方面，并为考虑宿主-寄生虫相互作用提供了新的范例。
