FIGURE 1.

ACE2 expression in the human ENS of the small intestine. (A) Overview of the entire gut wall of a small intestinal segment with immunofluorescence stainings for ACE2 (red), the glial marker S100b (green), and with the nuclear marker DAPI (blue). The white rectangles indicate the location of the high power magnification micrographs below showing a representative submucous and myenteric ganglion. (B,C) show representative submucous and myenteric ganglia stained for ACE2 (red), DAPI (blue), and the neuronal markers PGP9.5 (B, red) or HuC/D (C, red). Clearly, a positive staining can be found in enteric neurons and, less intense, in glial cells. The overview is a standard epifluorescence image; details are maximum intensity projections of optical sections by structured illumination. Scale bars: overview 250 μm; details 50 μm.