In a pioneering development, researchers at the Rensselaer Polytechnic Institute (RPI) have accomplished a significant advancement in 3D printing by successfully incorporating hair follicles into human skin tissue. Dr. Pankaj Karande, the lead researcher and Associate Professor of Chemical and Bioengineering at RPI, led the groundbreaking study, marking the first instance of 3D printing incorporating hair follicles into lab-grown human skin.
The study, published in October 2023 and titled “Incorporating hair follicles into 3D bioprinted models of human skin,” demonstrates the potential of 3D printing to revolutionize drug testing and skin grafting procedures. The researchers’ approach distinguishes itself by not only introducing hair follicles into skin models but also employing a unique 3D printing technology.
Historically, reconstructing hair follicles using human-derived cells presented challenges. Dr. Karande’s team built upon previous studies suggesting that three-dimensional environments could spur the development of new hair follicles or hair shafts. The researchers cultivated skin and follicle cells in the laboratory, processing them into bio-ink for a specialized 3D printer.
Critical to the process was the multiplication of skin and follicle cells in the laboratory to ensure a sufficient supply of printable cells. The researchers combined each cell type with proteins and other materials, creating a printable bio-ink applied to a wafer-thin needle. The printer then meticulously layered the skin model, concurrently establishing channels for depositing hair cells, effectively embedding them in the structure.
Over time, the channels surrounding the hair cells filled with skin cells, replicating the intricate follicular structure of human skin. Dr. Karande emphasized that their work serves as a proof-of-concept, demonstrating the precise and reproducible creation of hair follicle structures using 3D bioprinting. The automated process showcased in the study is a critical step toward the future biomanufacturing of skin.
Although the current lifespan of the 3D-printed skin tissue with hair follicles is limited to two to three weeks, preventing the maturation of hair shafts, the study represents substantial progress. The researchers aim to extend the lifespan of skin tissue to facilitate the continued maturation of hair follicles, offering possibilities for drug testing and skin transplants.
While contemporary skin models used in medical testing are relatively simple, the addition of hair follicles enhances their complexity, providing deeper insights into how skin interacts with topical products. The researchers foresee the impact of this technology on regenerative medicine and cosmetic testing, enabling the creation of more sophisticated and biologically relevant skin models.
Dr. Karande’s lab has been a trailblazer in skin tissue engineering, having previously succeeded in printing skin with functional blood vessels. This recent research marks another significant stride toward advancing treatments for burns and various skin conditions.
