Bidimensional models of the BBB have been created through the addition of glia to the Transwell system with various levels of success (Figure 1). In doing so, investigators were able to mimic at least one of the fundamental aspects of the BBB, that is, glial-endothelial interactions. It has been well known for some time that glial cells exert a yet unknown influence on their neighboring endothelial counterparts. The nature and significance of this interaction is poorly understood, but it is clear however, that at least in vitro these cells do interact and that glial cells induce BBB properties in endothelial cells. Interestingly, the efficacy of glia to induce BBB properties in endothelial cells is not limited to cerebral endothelial cells since investigators were able to induce BBB properties in nonbrain endothelial cells as well .
The main advantage of the bidimensional model, compared to monodimensional, is the attempt to closely mimic the in vivo situation. Thus, the addition of glial cells has led to a decrease in transendothelial leakage. However, this model may also experience some "nonphysiological leak" as well, thus making it more difficult to predict or estimate permeation across the BBB of pharmacological agents or other molecules. Other than those already stated, there are no obvious pitfalls, besides that a source of glial cells is essential, which slightly increases the required skills of the investigator/scientist (Table I).
Was this article helpful?
This ebook provides an introductory explanation of the workings of the human body, with an effort to draw connections between the body systems and explain their interdependencies. A framework for the book is homeostasis and how the body maintains balance within each system. This is intended as a first introduction to physiology for a college-level course.