Scientists Successfully Transform Stem Cells Into Cartilage Tissues Using 3-D Bioprinting

Researchers from the Sahlgrenska Academy, in collaboration with researchers from Chalmers University of Technology and Kungsbacka, have successfully transformed stem cells into cartilage tissues using 3-D bioprinting technology.

The result of their research project, described in a paper published in the journal Scientific Reports, showed that the structure of the bioprinted cartilage tissue from stem cells can be comparable to real cartilage.

"In nature, the differentiation of stem cells into cartilage is a simple process, but it's much more complicated to accomplish in a test tube," said Stina Simonsson, Associate Professor of Cell Biology and lead author of the study, in a press release. "We're the first to succeed with it, and we did so without any animal testing whatsoever."

For the study, the researchers first harvested cartilage cells from patients who underwent knee surgery. They then manipulated the cells in the laboratory to revert it back into pluripotent stem cells. The researchers expanded and encapsulated the stem cells in a composition of nanofibrillated cellulose.

Using a 3-D bioprinter, the stem cells were printed into a structure. After being printed, the stem cells were given growth factors to make them differentiate correctly, forming into cartilage tissues.

The researchers noted that the stem cells were able to survive the printing process, thanks to its individual nanocellulose casings. To encourage the multiplication of the printed cells, the researchers harvested mediums from other cells containing signals used by stem cells to communicate with each other. Basically, the researchers tricked the stem cells into thinking that they are not alone, making the cells multiply before they differentiated them.

Experienced surgeons found no differences when they compared the bioprinted tissue against a real cartilage, stating that the bioprinted tissue has properties similar to their patients' natural cartilage.Under the microscope, the cells in the bioprinted cartilage appear to be perfectly formed. Additionally, the bioprinted cartilage presents similar structure to those observed in human-harvested cartilage.