A standardized in vitro bioengineered skin for penetrating wound modeling

Over the years, significant progress has been made in developing cost-effective and ethical in vitro bioengineered skin substitutes to study cutaneous wound healing processes. Rodents and small animal models are not optimal due to physiological differences in their skin compared to human skin. The generation of reproducible and precise wounds is key to obtaining comparable results. We created a three-dimensional skin wounding model by growing a fully differentiated, stratified squamous epithelium from human keratinocytes at an air-liquid interface on a type I collagen scaffold concealed with human dermal BJ fibroblasts. To generate the wounds, a stamp with incorporated needles with a length of 250 µm was used to puncture the epidermis to produce standardized wounds. The stamping needle technique is a practical and inexpensive method for creating length-tailored wounds on three-dimensional skin models. The effectiveness of this technique in treating 3D skin models was demonstrated, accompanied by an evaluation of the model's functionality in terms of cell proliferation, differentiation, and immunological characteristics.