Fig. 4: The effect of Vav2 in epidermis is keratinocyte autonomous.

a Hematoxylin-eosin- (top) and Ki67- plus hematoxylin-stained (bottom) tissue sections from organotypic cultures using neonatal keratinocytes of indicated genotypes. The thickness of the corneum and cellular epidermal strata is indicated with red and blue brackets, respectively. Scale bar, 10 μm (n = 6 independent cultures). b Thickness of the indicated skin strata according to data from a. ***P < 0.0001 (two-tailed Student’s t-test, n = 6 independent cultures). c Representative images of indicated organotypic cultures after staining with hematoxylin-eosin (top panels) and antibodies to Ki67 (middle panels), involucrin (IVL, bottom, red color), and keratin 14 (K14, green color). Some of the sections were subsequently counterstained with either hematoxylin (middle row of panels) or DAPI (bottom panels, blue color). Scale bar, 10 μm. n = 8 (Mock and Vav2^Onc) and 5 (Vav2^Onc+E200A). d Thickness of the indicated skin strata according to data obtained in c. *P = 0.029; ***P < 0.0001 (two-tailed Student’s t-test, n as in panel c). e GTP-bound levels of Rac1, RhoA, and Cdc42 in indicated cells. *P = 0.013; **P = 0.002; ***P < 0.0001 (ANOVA and Tukey’s HSD test, n = 3 independent experiments). f Histological sections of 3D cultures of human keratinocytes expressing indicated proteins. Scale bar, 10 μm (n = 5 independent cultures). g Thickness of the indicated epidermal strata according to data from f. *P = 0.047 (Vav2^Onc corneum stratum), 0.011 (Rac1^F28L corneum stratum), 0.033 (Cdc42^F28L corneum stratum); **P = 0.003 (Cdc42^F28L cellular stratum); ***P < 0.0001 (all other tests) (ANOVA and Dunnett’s multiple comparison test, n = 5 independent cultures). h Immunohistochemical staining of mock- and Rac1^F28L + RhoA^F30L-expressing human keratinocytes with antibodies to Ki67 (top panels), IVL (bottom, red color) and K14 (bottom, green color). Sections were counterstained with either hematoxylin (top panels) or DAPI (bottom panels, blue color). Scale bar, 10 μm (n = 3). In b, d, e, and g, data represent the mean ± SEM. Source data for this figure are provided as a Source Data file.