Choroid plexus organoids as a model of the blood-cerebrospinal fluid barrier to study Streptococcus suis infection

Streptococcus suis is a zoonotic pathogen that can invade the central nervous system (CNS) and cause meningitis in pigs and humans. The vascularized choroid plexus (ChP) epithelium, known as the blood-cerebrospinal fluid barrier (BCSFB), serves as a route for S. suis invasion of the CNS. In this study, we aimed to use human induced pluripotent stem cells (iPSC)-derived ChP organoids as an in vitro model to investigate S. suis interaction and infection at the BCSFB and the responses of ChP organoids to S. suis using transcriptomics. We also investigated whether the known plasminogen (Plg) binding to S. suis surface enolase and its conversion to proteolytic plasmin (Pln) would facilitate S. suis translocation across the ChP organoid epithelium and alter the ChP response to infection.