Researchers at the New York Stem Cell Foundation have developed a technique to produce bioengineered bone grafts for large bone defects, which are currently difficult to treat using conventional techniques.
To deal with bone defects, clinicians currently use either synthetic materials or bone grafts from the patient or a donor. However, these grafts can trigger an immune response, and do not always integrate with the surrounding bone. “Bone defects obtained in disease or injury are a growing issue, and having effective treatment options in place for personalized relief, no matter the severity of a patient’s condition, is of critical importance,” said Giuseppe de Peppo, a researcher involved in the study.
One solution is to use biomaterials seeded with patient-specific stem cells to create bioengineered bone grafts. However, it is difficult to create bioengineered grafts for large bone defects, as getting cells to grow throughout a large scaffold is problematic.
“As the size of the defect that needs to be replaced gets larger, it becomes harder to reproducibly create a graft that can move from the lab to the clinic,” said Dr. Martina Sladkova, another researcher involved in the study. “We wanted to see if we could instead engineer smaller segments of bone individually and then combine them to create a graft that overcomes the current limitations in the size and shape of a bone that can be grown in the lab.”
The method involves mapping the bone defect using CT imaging, and then producing a customized biomaterial scaffold using computer manufacturing techniques. By producing the scaffold in small segments, the researchers can then grow patient-specific stem cells on the segments in a bioreactor. The bioreactor ensures that the cells grow uniformly throughout each scaffold segment. Once the segments are ready, the researchers assemble them in the large bone defect using a biocompatible bone adhesive to create an intact bioengineered bone graft.
So far, the researchers have tested the technique in rabbits, in a large femur defect that accounted for 30% of the bone volume, creating a mechanically stable bone graft. They hope that the approach will eventually help patients suffering from large bone defects.
See a video about the project here:
Study in Scientific Reports: Segmental Additive Tissue Engineering…