Dr. Ali Tamayol, Associate Professor, Biomedical Engineering Department at the University of Connecticut School of Dental Medicine had recently invented a handheld 3D bioprinter which can be deployed directly on affected sites with damaged or weakened skeletal muscles for surgeons to release scaffolds that facilitate cellular and tissue repair or growth. This invention believed will change how musculoskeletal surgical procedures are being performed presently. Related finding was published in the American Chemical Society Journal.
Existing challenges in reconstructive surgery
Dr. Indranil Sinha, Plastic Surgeon specializing in the treatment of muscle injuries at Brigham and Women’s Hospital was also part of the research team. He pointed out that 3D bioprinting has become an up and coming antidote for contemporary reconstructive surgery methods that are not adequate to treat patients suffering from volumetric muscle loss. Dr. Sinha believes the customizable gel released from the portable 3D bioprinter will initiate a foundation for a new treatment paradigm to enhance the care for trauma patients.
However, 3D bioprinting is not without its own challenge. Biomaterials that bond well with the cells and tissues around the affected areas are highly specific and they need to be successfully printed out before a hydrogel-based scaffold can be constructed. Thus far, 3D bioprint scaffold which resembles human skeletal muscle has only been done in laboratory settings and has yet to be used on human patients.
Dr. Tamayol’s solution is to develop some kind of a “bioink”, or gelatin-based hydrogels. Previous animal studies found that such material adheres well to the surrounding tissues within defect sites and eliminates the need for suturing. Mice suffering from volumetric muscle loss injuries demonstrated a significant increase in muscle hypertrophy after treatment.
“The printer is robust and allows proper filling of the cavity with fibrillar scaffolds in which fibers resemble the architecture of the native tissue. It also enables clinicians to directly print the scaffold within the patient’s body. Best of all, this system does not require the presence of sophisticated imaging and printing systems,” says Dr. Tamayol.
The use of handheld 3D bioprinter on large skin burns
Around the same time, Richard Cheng, PhD candidate at the University of Toronto, his supervising professor Axel Guenther and Dr. Marc Jeschke, Director of the Ross Tilley Burn Center and his team at Sunnybrook Health Sciences Centre had created a handheld 3D bioprinter meant for patients with severe large area burns.
According to Dr. Guenther, most 3D bioprinters are huge, costly and work at low speed, they are not compatible with other clinical applications and are difficult to deploy in middle- or low-income countries where deaths caused by burns are high. Besides, the current method of care for burns – autologous skin grafting (i.e., transplanting healthy skins from other parts of the patients’ body onto the affected area) is not sufficient to heal large or even full-body burns because most burns destructed not only the outer but also the inner layer of the skin.
The newly devised handheld 3D bioprinter will be a relatively user-friendly mean to roll out sheets of mesenchymal stroma cell (MSC) bioink on areas suffering from serious burns. MSC are stem cells that can be differentiated into various specialized cells depending on the environment. Over here, MSC promotes regeneration of new skin and reduces scars.
The handheld 3D bioprinter had undergone 10 redesigning processes since prototype debut in 2018. The latest prototype comes with a once-off microfluidic printhead for sterilization purpose and a soft wheel for better application control over the wound. The research team hopes the final product can be used by surgeons in operating room within the next five years.