Figure 6. Deficient differentiation in the skin of K5-CYLDC/S mice. Representative immunostainings of the back skin of 20-month-old mice (A-J). Observe the strong expression of the epidermal differentiation proteins Involucrin, Loricrin and Filaggrin in the suprabasal layers of the epidermis of Control mice (A,C,E,G); and the weak and discontinuous expression of these proteins in the epidermis of K5-CYLDC/S mice (B,D,F,H), specially faint in the areas of epidermal atrophy (red brackets). (I, J) Representative images corresponding to the immunostaining of the back skin of Control (I) and transgenic (J) mice with the K5 specific antibody. (I) Strong K5 staining in basal keratinocytes of Control mice. A faint and patched expression is detected in the epidermis of the transgenic mice, especially in the regions of atrophic epidermis (indicated by red brackets). Scale bars: 180 μm (A-H); 150 μm (I, J).