Anti-vWF Immunofluorescence in Mouse Brain

The blood-brain barrier (BBB) blocks molecules larger than about 500 Daltons from escaping the brain vasculature and accessing the neurons and glia of the brain. While the BBB serves an important protective role for the brain, it also blocks access of most therapeutic reagents and is thus an obstacle for the treatment of many disorders of the nervous system. To determine whether intravenously administered experimental therapeutic reagents are able to cross the BBB in animal models of disease, it is necessary to determine the location of the reagents relative to the vasculature; methods for labeling the vasculature are useful for such studies. Here, we carried out immunofluorescent labeling of the vasculature in mouse brain tissue sections with an antibody specific for von Willebrand Factor, a protein expressed on the surface of brain endothelial cells. We explored fluorophores with red and “far red” emission spectra because brain tissue exhibits a lower level of autofluorescence at longer wavelengths. We obtained comparable results with secondary antibodies coupled to either red or far red emitting fluorophores.