Researchers at the University of São Paulo’s School of Pharmaceutical Sciences conducted a study on bioengineered artificial skin and its use as a platform for testing the safety and efficacy of drugs and cosmetics. The results were reported in an article published in the journal Bioprinting. Artificial skin can be produced on a large scale and can serve as a good substitute for animal testing. One of the most promising technologies for its production is 3D bioprinting, which has not yet been sufficiently validated compared to traditional, manually produced models. The researchers compared the conventional mimetic model based on manual pipetting with extrusion bioprinting and found that the bioprinted skin achieved a similar performance.
The study used quality control and performance assessment standards established by international institutions like the Organization for Economic Cooperation and Development (OECD) as validation criteria. The tissue morphology of the bioprinted skin was first assessed and found to be representative of human skin in vivo. The next step was to test its function as a barrier and its ability to prevent the penetration of detergents, such as sodium dodecyl sulfate (SDS), that cause irritation. The last validation test was a topical application of reference chemicals classified as irritants or non-irritants. The results showed that both the bioprinted skin and the manually reconstructed skin were consistent with internationally validated epidermic models, and they responded equally well to irritants and distinguished between irritants and non-irritants.
The results of the study prove that the bioprinted skin can be used instead of the Draize test, which is an acute toxicity test that applies the substance directly to rabbit skin. The use of bioprinted skin not only avoids animal testing but also reduces human error and variability in the responses obtained by the cosmetics industry. The researchers noted the need for caution in using bioprinters as the dispersion system chosen can damage the reliability of the tests by leading to altered responses, such as increased inflammation. The researchers plan to bioprint more complex models comprising the epidermis, dermis, and hypodermis with representative human skin cells to produce more biologically relevant responses in safety and efficacy testing of products for topical use.
The study was supported by the São Paulo Research Foundation (FAPESP) and Natura, a major Brazilian cosmetics company. Natura funded part of the development of the bioprinter used to make the reconstructed skin. The business-university partnership allowed for the acceleration of the application of knowledge in the tissue reconstruction project and automation via bioprinting, which is important for the company.
The use of bioengineered artificial skin as a platform for testing the safety and efficacy of drugs and cosmetics is becoming increasingly important and reliable. With the use of bioprinting technology, it is possible to produce high-quality, reliable artificial skin that can serve as an alternative to animal testing. The study conducted by the researchers at the University of São Paulo’s School of Pharmaceutical Sciences confirmed that bioprinted skin can achieve a similar performance to traditional, manually produced models.
However, caution must be taken in the use of bioprinters, as the dispersion system chosen can impact the reliability of the tests. Further research is needed to bioprint more complex models to produce more biologically relevant responses in safety and efficacy testing.