Crossing Barriers: How Streptococcus suis Hijacks the Plasminogen-Plasmin Proteolytic System to Invade the Brain

Summary

Streptococcus suis is a zoonotic bacterium that causes invasive diseases in pigs and humans. S. suis infection of the human brain can lead to serious meningitis, with high mortality and long-term complications such as hearing loss. The mechanisms by which S. suis invades the brain and the factors affecting its harmfulness are not fully understood. This thesis developed human stem cell-based in vitro models that closely mimic protective barriers in the human brain, and used these models to investigate how S. suis interacts with the brain barriers. The findings provide new insights into the mechanisms of S. suis invasion of the brain and highlight the role of a surface-exposed protein of S. suis in facilitating the bacterial invasion.