Advancements in Listeria monocytogenes infection of brain microvascular endothelial cells and crossing the blood-brain barrier

The blood-brain barrier (BBB) is a key interface for the exchange of nutrients and other biomolecules between blood and brain parenchyma, and it also acts as a barrier against neurotoxic exogenous agents in the bloodstream. A BBB structural unit includes brain microvascular endothelial cells (BMECs), pericytes, and astrocytes. Among these components, BMECs possess tight junctions that are distinct from those found in other types of endothelial cells. This unique molecular property forms a natural barrier that hinders pathogenic bacteria from entering the brain parenchyma. Listeria monocytogenes (LM), a resilient and potentially deadly pathogen with significant public health implications, is capable of infecting BMECs and crossing the BBB, causing encephalitis, meningitis, and other serious brain diseases. This review encapsulates the various types of BMECs and the latest advancements in establishing in vitro BBB models utilizing BMECs. Then, possible physiological mechanisms of LM crossing the BBB were systematically outlined, offering theoretical insights for comprehensively understanding how LM crosses the BBB and for efficiently preventing and controlling it.