Figure 3. IL-33 is constitutively expressed in the nucleus of endothelial cells from large blood vessels in normal human tissues.

Expression of IL-33 in human tissues was analyzed using both immunohistochemistry (lefts panels) and immunofluorescence staining (right panels). Double staining was performed with IL-33 mAb Nessy-1 (red) and anti-CD31 or anti-vWF polyclonal antibodies (green). DNA was counter-stained with DAPI. Arrowheads label the nuclei of smooth muscle cells in arterioles that are not stained with IL-33 antibodies. Magnification bars: 35 µm.