Research Paper Volume 15, Issue 22 pp 12702—12722

Figure 5. Aged EVs impact proliferation of young keratinocytes in 2D culture. (A) Primary keratinocytes were treated with DAPI only (a, c) or by DAPI plus fluorescently labeled (CM-Dil) EVs from young keratinocytes culture medium (b, d). A part of image d is shown with higher magnification in (e, f, g). (B) Proliferation profile of young cultured keratinocytes treated with EVs purified from young or aged keratinocytes. DNA concentration in treated keratinocytes was measured 24 h, 48 h and 72 h after the beginning of the treatment. (^*p-value < 0.05. ^**p-value < 0.01. n = 3 Student’s t-test). (C) Expression analysis of transcripts for P21, P16, P53, KRT1 (K1), KRT10 (K10) and loricrin in young keratinocytes treated with EVs from old keratinocytes. Data were normalized to the non-treated condition. (^*p-value < 0.05. n = 3 Student’s t-test).