Customized biomaterial scaffolds and perfusion inserts for culture. (Credit: New York Stem Cell Foundation)

A new bone engineering technique allows researchers to combine segments of bone engineered from stem cells to create large-scale, personalized grafts that will enhance treatment for those suffering from bone disease or injury through regenerative medicine.

Called Segmental Additive Tissue Engineering (SATE), the technique is standardized, versatile, and easy to implement, allowing for bioengineered bone grafts to more quickly make the leap from bench to bedside, and the researchers are confident in its potential to enable bone graft engineering that will help to improve the quality of life of pediatric and adult patients suffering from segmental bone defects.

The team engineered a graft corresponding to a defect in the femur of a rabbit that affected about 30 percent of the bone’s total volume. They first scanned the femur to assess the size and shape of the defect and generated a model of the graft. They then partitioned the model into smaller segments and created customized scaffolds for each.

The team then placed these scaffolds, fitted with human induced pluripotent stem cell-derived mesodermal progenitor cells, into a bioreactor specially designed to accommodate bone grafts with a broad range of sizes. This bioreactor was able to ensure uniform development of tissue throughout the graft, something that existing versions of bioreactors often struggle to do.

Once the cells integrated and grown within the scaffold, the segments of the bone graft could then be combined into a single, mechanically stable graft using biocompatible bone adhesives or other orthopedic devices.