Density of attachment of B. pilosicoli cells to Caco-2 cells after 2, 4 and 6 h incubation.*

*Results are derived from 12 fields of view. They are median (and the range) at each time point, where 0 represents no attachment observed and 5 represents the entire surface of the field covered with spirochetes such that the Caco-2 cell surface was not visible.*本研究结果源自12个视场（field of view）。各时间点的统计值为中位数及全距，其中0代表未观察到螺旋体黏附，5表示该视场的整个表面均被螺旋体覆盖，以致Caco-2细胞表面完全不可见。