Advancing the in vitro drug screening models: Microbiome as a component of tissue-engineered skin

Currently, in vitro skin models are among the most advanced and frequently utilized tools in clinical practice and drug screening. The development of these models often involves the use of skin organoids and biofabrication techniques, such as 3D bioprinting. Despite this significant progress, the skin models employed in drug screening typically lack a microbiome component. Since the microbiome is recognized as a crucial element of healthy human skin, it is essential to integrate this aspect into existing skin models. This review outlines a pathway for the development of in vitro skin models that can be widely used as platforms for testing drugs and cosmetics. First, we discuss the diversity of the normal human microbiome and its interactions with human cells. Next, we examine current skin models, including those that incorporate microbiome components through various co-culturing methods. Finally, we discuss how biofabrication approaches can be combined with microbiome elements to create relevant and stable in vitro skin models.