Figure 4From: Exome sequencing identifies a missense mutation in Isl1associated with low penetrance otitis media in dearisch miceHematoxylin and eosin staining of the middle ear in adult mice. (a, b) The middle ear of an unaffected animal. This has a clear middle ear cavity (MEC), external auditory canal (EAC) and a thin, single cell mucosal lining of the cavity. (c, d) An affected animal with a normal EAC, but effusion within the MEC and a thickened mucosa, with fibroblasts, granulocytes and granulation tissue. (e) A magnified view of the effusion in an affected animal, containing foamy macrophages and neutrophils. M, malleus. Scale bars: 100 μm (a, c); 20 μm (b, d, e).Back to article page