Research Paper Volume 16, Issue 9 pp 7511—7522

Figure 2. Biological properties of HDF, HaCaT, and ARPE-19 after UV exposure with two different lamp sources: Purple Dawn (PD) and HVC2654025-16W (HVC). (A) The histograms show the percentage of apoptotic cells identified by the Annexin V assay. This staining enabled the classification of cells into four populations: early and late apoptotic cells, live cells, and necrotic cells. In the graph, early and late apoptotic cells were combined as a single group (n = three ± SD) ^*p < 0.05; ^**p < 0.01; ^***p < 0.001. (B) The histograms show the percentage of necrotic cells identified by the Annexin V assay (n = three ± SD). ^*p < 0.05; ^**p < 0.01; ^***p < 0.001. (C) The pictures show representative β-galactosidase staining assay (size bar corresponds to 100 μm). Meanwhile, the histograms show the percentage of senescent cells determined by counting the cells that appear in blue (n = three ± SD). ^*p < 0.05; ^**p < 0.01; ^***p < 0.001.