An endometrial organoid model ofChlamydia-epithelial and immune cell interactions

Abstract

ABSTRACTOur understanding of how the obligate intracellular bacteriumChlamydia trachomatisreprograms the cell biology of host cells in the upper genital tract is largely based on observations made in cell culture with transformed epithelial cell lines. Here we describe a primary spherical organoid system derived from endometrial tissue to recapitulate epithelial cell diversity, polarity, and ensuing responses toChlamydiainfection. Using high-resolution and time-lapse microscopy, we catalogue the infection process in organoids from invasion to egress, including the reorganization of the cytoskeleton and positioning of intracellular organelles. We show this model is amenable to screeningC. trachomatismutants for defects in the fusion of pathogenic vacuoles, the recruitment of intracellular organelles, and inhibition of cell death. Moreover, we reconstructed a primary immune cell response by co-culturing infected organoids with neutrophils, and determined that the effector TepP limits the recruitment of neutrophils to infected organoids. Collectively, our model details a system to study the cell biology ofChlamydiainfections in three dimensional structures that better reflect the diversity of cell types and polarity encountered byChlamydiaupon infection of their animal hosts.Summary statement3D endometrial organoids to modelChlamydiainfection and the role of secreted virulence factors in reprogramming host epithelial cells and immune cell recruitment