ULTRASTRUCTURE OF THE MURINE CERVIX FOLLOWING INFECTION WITH CHLAMYDIA-TRACHOMATIS

We have used electron microscopy to follow the course of Chlamydia tra chomatis infection in the mouse cervix. Although numerous elementary b odies (EBs) were observed on the surface of epithelial cells, evidence of coated pits or entry of EBs into epithelial cells were rarely obse rved. After 2 days postinoculation, inclusions contained numerous reti culate bodies (RBs) and a few intermediate forms (IBs). At 4 days post inoculation, microvilli were no longer present on infected cells and i nclusions had often ruptured and released chlamydiae into the cytoplas m of the cells. Aberrant and miniature RBs, similar to those which hav e been described in in vitro models for persistence, were observed. Un like the case in vitro where inclusions cause rupture of the cell, inf ection in vivo may result in rupture of inclusions within the cytoplas m of infected cells. Our observations also suggest that persistent chl amydia can form in some of the cells of the cervical epithelium that a re infected by the initial inoculation.