T. vaginalis, a human-infective parasite, causes the most common nonviral sexually transmitted infection (STI) worldwide and contributes to adverse inflammatory disorders. The immune response to T. vaginalis is poorly understood. Neutrophils (polymorphonuclear cells [PMNs]) are the major immune cell present at the T. vaginalis–host interface and are thought to clear T. vaginalis. However, the mechanism of PMN clearance of T. vaginalis has not been characterized. We demonstrate that human PMNs rapidly kill T. vaginalis in a dose-dependent, contact-dependent, and neutrophil extracellular trap (NET)-independent manner. In contrast to phagocytosis, we observed that PMN killing of T. vaginalis involves taking “bites” of T. vaginalis prior to parasite death, using trogocytosis to achieve pathogen killing. Both trogocytosis and parasite killing are dependent on the presence of PMN serine proteases and human serum factors. Our analyses provide the first demonstration, to our knowledge, of a mammalian phagocyte using trogocytosis for pathogen clearance and reveal a novel mechanism used by PMNs to kill a large, highly motile target.

Ť。阴道炎是一种人类感染性寄生虫，引起全世界最常见的非病毒性传播感染（STI），并导致不良的炎症性疾病。对T的免疫反应。阴道了解甚少。中性粒细胞（多形核细胞[PMNs]）是T上主要的免疫细胞。阴道-host接口和被认为是明确的牛逼。阴道。但是，T的PMN清除机制。阴道炎尚未被鉴定。我们表明，人类的中性粒细胞迅速杀灭牛逼。阴道炎以剂量依赖性，接触依赖性和嗜中性粒细胞胞外捕获（NET）无关的方式。相反吞噬作用，我们观察到PMN杀的牛逼。阴道涉及服用“咬”牛逼。寄生虫死亡前阴道，利用光吞作用达到杀死病原体的目的。吞噬作用和杀寄生物均取决于PMN丝氨酸蛋白酶和人血清因子的存在。据我们所知，我们的分析为利用吞噬作用清除病原体的哺乳动物吞噬细胞提供了第一个证明，并揭示了PMN杀死大的高运动性靶标的新机制。