摘要支原体是能在无生命培养基中生长繁殖的最小原核细胞型微生物，其种属较多，可广泛寄生于人体、哺乳动物、鸟类及植物中，有很强的致病性。支原体具有独特的生物学结构和功能，其具体的致病机制尚不清楚。近年来研究表明，支原体能在宿主体内的持续性感染是其致病的主要原因。在与宿主的长期共同进化过程中，支原体形成了多种逃逸宿主免疫反应的生存方式，以逃避宿主的免疫应答。

abstractsMycoplasmas(class Mollicutes)are the smallest prokaryotic organisms that can be self-replicating on laboratory media. These microorganisms are widespread parasites of man, animals, insects and plants. However, the concrete pathogenic mechanisms are still unknown. Recently, more and more studies have shown that Mycoplasmas can reside and replicate intracellularly over extended periods in human cells, consistent with the ability to circumvent immune defense and establish chronic infections. The major mechanisms for its immune escape that have been studied on are anti-phagocytosis of capsule, adhesion and invasion to hosts cells, antigen variation and molecular mimicry.