Despite being the largest in the human body it’s easy to forget about skin as an organ, unless your research or practice directly involves it. It’s what we use to interact with the world and present ourselves. No one else, other than doctors, will really start thinking about your spleen or pituitary gland when they look at you. But just as with any other cell type, there is great research being conducted around skin.
Last time, on our Amazing Samples blog series, we discussed some points of research and applications of T-cells. This time, let’s scratch the surface of the research that is making skin an Amazing Sample.
Yet Another Transformation
Considering we’ve discussed researchers transforming cells from one type to another – bone marrow cells into natural killer cells, and fibroblasts into striatal neurons – it’s no surprise that we’d touch on this topic again. Two years ago, researchers at the University of California San Francisco published results on the ability to transform skin cells into working cells from a number of other organs, most excitingly the liver. Anyone who has studied the basics of metabolic biochemistry will remember how important this organ is – ethanol, fatty acids, non-glucose sugars, and many more are exclusively broken down in the liver.
These researchers were not only able to convert skin cells into liver-like cells, but mature ones that could perform metabolic activity, and were fully functional two months after transplantation into an animal model. This fact was not only exciting for the implications of treating hepatic conditions such as liver failure, but in general for all sorts of cell therapy – taking especially abundant tissue like skin and turning the cells into other types as needed is nearly a biochemical equivalent to alchemy!
But skin cells aren’t involved in just one side of the transformation. In 2013, a group of Spanish researchers had developed a technique to transform Wharton’s jelly stem cells into epithelial cells. While the transformation happened in vitro, it was found that upon in vivo grafting the cells expressed all typical biomarkers of fully functional epithelial cells. One of the researchers commented that while the skin created in this way would require weeks to grow before being ready for a graft, it would make more sense to create it well ahead of time and store it in a tissue bank for immediate access when needed – classic allogeneic therapy strategy. For the millions of moderate to severe burn victims worldwide, as reported by the World Health Organization, technology like this would be able to greatly decrease not only time of recovery and fatality risk from infection, but also potentially the cost of care.
Home-Grown Skin for Research
As compared to the skin grown for grafting purposes, a different group of researchers have developed a way to grow artificial skin tissue for research purposes, using a mix of human embryonic stem cells and induced pluripotent stem cells. This is currently being vetted for applications both in researching skin disorders of various types, and for testing of both cosmetic and pharmaceutical products.
While previously there has been difficulty creating human epidermal equivalents (HEEs) with fully developed epidermal barriers—the biggest functional purpose of the epidermis, therefore what would be most important to research factors’ impact on—these researchers’ HEEs have those barriers. Additionally, as the stem cells from which these HEEs are derived can proliferate indefinitely, this allows for the creation of any desired quantity of genetically identical skin cells. Past researching various skin disorders, this tissue would also be a cheaper alternative to testing on animal models for many cosmetic and pharmaceutical products, which would be especially welcome to cosmetic products that have been banned from the EU due to animal testing.
This ban is also driving other similar ventures, such as L’Oreal partnering with 3-D human tissue printing company Organovo, who has already been working with pharmaceutical companies for printing organs such as kidneys and livers. While L’Oreal has already been investing in skin research for decades, 3-D printing shows a massive improvement in time and efficiency over their current alternative – growing new cells from donated skin that would otherwise be discarded after plastic surgery. Company representatives stated that they are focusing on improving accuracy and consistency first, and will work on speed after refining the production process to a satisfactory level.
Developing Technology from Animal Skin
Now, this one, I really am going to barely scratch the surface. So many other species have evolved physiological traits that we could benefit from harnessing; it’s hard to cover all of the possibilities. One good example, especially considering 3-D printing, is biomimetic shark skin – through micro-CT imaging a mako shark’s skin, researchers were able to create skin covered with the rigid denticles that define the odd texture of shark skin. Interestingly, compared to relatively smooth skin, the denticle-covered skin allows for increased speed and decreased expended energy. While apparently engineers have been attempting to replicate the drag-decreasing function of denticles for years now, this is the most precise and labor-intensive effort, with a flexible membrane covered with thousands of the 0.15-mm denticles. The researchers are looking forward to further research, such as examining various other species’ denticle shapes, and testing for the corresponding hydrodynamic differences.
People may say that beauty is only skin deep, but “skin deep” research still gets pretty complex and varied. Clearly, skin too is an Amazing Sample. Do you work with skin cells or tissue in your project? Share your story in the comments below!
For related information about the optimal storage temperature for a wide array of samples, including skin and active proteins, download our InfoPoster Biobank Storage Temperatures: An Illustrative Guide below.