The blood-brain barrier (BBB) is a dynamic but solid shield in the cerebral microvascular system. It plays a pivotal role in maintaining central nervous system (CNS) homeostasis by regulating the exchange of materials between the circulation and the brain and protects the neural tissue from neurotoxic components as well as pathogens. Here, we discuss the development of the BBB in physiological conditions and then focus on the role of the BBB in cerebrovascular disease, including acute ischemic stroke and intracerebral hemorrhage, and neurodegenerative disorders, such as Alzheimer's disease (AD), Parkinson's disease (PD), and multiple sclerosis (MS). Finally, we summarize recent advancements in the development of therapies targeting the BBB and outline future directions and outstanding questions in the field. We propose that BBB dysfunction not only results from, but is causal in the pathogenesis of neurological disorders; the BBB is more a contributor to the disruption of CNS homeostasis than a victim in neurological disorders.

Background Listeria monocytogenes (L. monocytogenes) is a facultative intracellular bacterial pathogen which can invade different mammalian cells and reach to the central nervous system (CNS), leading to meningoencephalitis and brain abscesses. In the diagnosis of L. monocytogenes meningoencephalitis (LMM), the traditional test often reports negative owing to the antibiotic treatment or a low number of bacteria in the cerebrospinal fluid. To date, timely diagnosis and accurate treatment remains a challenge for patients with listeria infections. Case presentation We present the case of a 66-year-old woman whose clinical manifestations were suspected as tuberculous meningoencephalitis, but the case was finally properly diagnosed as LMM by next-generation sequencing (NGS). The patient was successfully treated using a combined antibacterial therapy, comprising ampicillin and trimethoprim-sulfamethoxazole. Conclusion To improve the sensitivity of LMM diagnosis, we used NGS for the detection of L. monocytogenes. Hence, the clinical utility of this approach can be very helpful since it provides quickly and trust results.