Scientists have developed a technique to directly convert the cells in an open wound of patients with, for instance, severe burns, bedsores or chronic diseases such as diabetes, into new skin cells. The approach relies on reprogramming the cells to a stem-cell-like state, and could be useful for healing skin damage, countering the effects of ageing and helping to better understand skin cancer, said California's Salk Institute in a statement. "Our observations constitute an initial proof of principle for in vivo (in a living organism) regeneration of an entire three-dimensional tissue like the skin, not just individual cell types as previously shown," said Salk Professor Juan Carlos Izpisua Belmonte, senior author of the new paper, which was published in the journal Nature. "This knowledge might not only be useful for enhancing skin repair but could also serve to guide in vivo regenerative strategies in other human pathological situations, as well as during ageing, in which tissue repair is impaired." In the image, epithelial (skin) tissues were generated by converting one cell type (red: mesenchymal cells) to another (green: basal keratinocytes) within a large ulcer in a laboratory mouse model.