Quantitative In Situ Analysis of Claudin Expression at the BloodRetinal Barrier

It is apparent that claudins are involved in signalling to and from cellular tight junctions (TJs) and control cell behaviour such as proliferation, differentiation, and migration. Methods to identify and measure specific claudins in TJs would, therefore, be useful to monitor TJ structure and functional integrity under physiological and pathological conditions. The molecular pathways involved in claudin signalling are not understood and are likely to become a focus for intensive research as better understanding of tight junction structure and function may provide opportunities for better drug delivery and absorption. In this chapter, we describe our method for quantitative analysis of specific claudins in TJ during the breakdown of the blood–retinal barrier in a mouse model of inflammatory uveitis, experimental autoimmune uveoretinitis (EAU).