In this blog post, we will look at the long-standing controversy surrounding animal testing and examine whether artificial skin “Episkin” can really be a realistic alternative.
Animal experiments have long been conducted in various fields, including medicine, beauty, and space development. Animal experiments have greatly contributed to the development of science, and their use is expected to continue in the future, making it difficult to stop them immediately. However, as the quality of life of mankind has improved and their lives have become more stable, people have become interested in animal welfare beyond human convenience and comfort. North America and Europe, which have achieved early development, have high standards of animal welfare and are contributing to the spread of the animal welfare movement around the world.
Among the many forms of animal testing, the first to show signs of discontinuation is experiments related to beauty, or the development of cosmetics. This is because the cruelty of animal testing conducted by companies for the development of cosmetics was revealed through the media, and the voices of criticism and opposition against it increased. As a result of the steady efforts of animal protection organizations and individuals, the European Union (EU) banned animal testing for cosmetics on March 11, 2013. This legislation not only bans animal testing for the development of cosmetics, but also prohibits the sale of cosmetics developed through animal testing in Europe. The ban on animal testing was made possible by the introduction of alternative testing methods.
Experiments related to cosmetics are broadly divided into two categories. The first is experiments conducted when developing new cosmetics, and the second is experiments to test the efficacy of finished cosmetics. Since both experiments are conducted repeatedly over a period of time, a large number of animals are used to develop a single cosmetic product. For example, there are skin sensitization tests to determine whether a product causes itching or irritation on the skin, eye irritation tests to determine the reaction of the eyes when cosmetics are applied, and repeated toxicity tests to evaluate the toxicity of the product when used for a long period of time.
A representative example of an alternative experiment is the use of artificial skin called Episkin instead of animals such as rabbits, rabbits’ ears, rabbits’ eyes, and mice, which were previously used in cosmetics development and efficacy testing. Episkin is an artificial skin made similar to human skin using skin cells, and is a suitable model to replace animal testing.
Episkin has all the major components of human skin: subcutaneous tissue, dermis, and epidermis. Cosmetics mainly work on the epidermis, and most of them are not absorbed into the dermis, so experiments on the epidermis are important. The epidermis is composed of keratinocytes, melanocytes, and Langerhans cells, which protect the skin and play an immune role. However, since the effects of cosmetics on the human body cannot be accurately determined based on the epidermis alone, the artificial skin used in alternative experiments must include the subcutaneous tissue, dermis, and epidermis, all of which are similar to the structure of the skin. Episkin has all three of these components, making it suitable for replacing animal testing.
Since Episkin is made using actual skin cells, it can form a structure similar to human skin. The skin cells used to produce Episkin are obtained through methods such as obtaining consent and donating. The skin cells are cultured in a culture solution containing collagen gel, and after they grow to a certain extent, they are immersed in a mixture of water, sugar, and amino acids. Exposing this sample to the air for about 10 days creates a surface that is similar to real skin.
The advantage of Episkin is that it can mimic various skin conditions of humans, not just as an alternative to animal testing that sacrifices animals. Unlike humans, animals cannot easily express various skin colors or aging conditions, but Episkin can embody various characteristics of human skin under various conditions. For example, it can express skin with different levels of aging depending on the degree of exposure to ultraviolet (UV) rays, and it can also create various skin tones depending on the amount of melanin cells injected. This can also contribute to the development of cosmetics suitable for the skin tones of different ethnicities.
In addition to replacing unethical animal testing, Episkin, which is more similar to human skin than animal skin, plays an important role in cosmetics testing. In countries that actually prohibit or restrict animal testing, artificial skin models such as Episkin are commonly used. Episkin has shown clear differences in skin irritation and allergic reactions in experiments using existing cosmetics, and its usefulness has been proven. For this reason, there are many predictions that alternative models such as Episkin will gradually become widely used even in countries that still conduct animal testing.
