The delivery of many potentially therapeutic and diagnostic compounds to specific areas of the brain is restricted by brain barriers, the most well-known of which are the blood-brain barrier (BBB) and the blood-cerebrospinal fluid barrier. There are numerous additional roles of these barriers, including an involvement in neurodevelopment, control of cerebral blood flow, and, when barrier integrity is impaired, a contribution to the pathology of common CNS disorders such as Alzheimer’s disease, Parkinson’s disease, epilepsy and stroke. The blood-brain barrier is morphologically composed of cerebral microcapillary endothelium surrounded by pericytes and astrocytes. This barrier function is mainly achieved by two components in the brain capillary endothelium: ATP-driven Membrane transporters known as ‘efflux transporters’ and tight junctions that ‘seal’ spaces between endothelial cells.
In vitro models of the blood-brain barrier are suitable tools to study drug transport, pathogen transmigration and leukocyte diapedesis across the cerebral endothelium. However, there are currently no in vitro models that comprise a full reconstruction of the blood brain barrier and the neurovascular junction in a dynamic 3D system, mimicking also the blood flow. We have recently developed an artificial microvasculature (μ3DVasc), which is composed of a microfluidic, microvascular curvilinear channel structure, which can be coated with a confluent endothelial layer. It is surrounded by microfluidic compartment, which can be used for 3D-cultures of pericytes, astrocytes and other neuronal cells involved in the formation of the BBB.
Aim of the proposal is to characterize and analyze this in vitro model and the integrity of the BBB formation in comparison to freshly isolated brain capillaries Besides the tightness of the barrier the transport activity of P-glycoprotein will be studied by adding the fluorescent P-glycoprotein Substrate NBD- Bodipy-ivermectin and its inhibitor PSC833.