As the cell matrix expanded, the PGA was slowly degrading; By the time the engineered ear was ready for implantation, it was primarily composed of the child’s native tissue and only small amounts of artificial material remained.
Meanwhile, a tissue expander was slowly stretching the skin over the extraction site in order to make room for the large implant. Once ready, the cultured cartilage was carefully placed in the skin pocket by plastic surgeons.
Over the next 2.5 years, patient one was monitored and underwent several cosmetic surgery adjustments. Tiny tissue samples removed during these procedures proved that the chondrocytes remained healthy and continued to produce cartilage comparable to that of a natural ear.
Moreover, the only artificial substance remaining in the engineered ear was part of the PCL core – as intended. Previous attempts to implant cultured ears have failed because the tissue used was not rigid enough to maintain its shape against the physical assaults of daily life. The Chinese team’s ear appears to be holding up well, although they note that its long-term integrity – after the PCL core fully degrades by year four – remains unknown.
Unfortunately, the next four patients showed less consistent results. One child’s new ear failed to produce new cartilage and the others are less refined aesthetically. All patients will be monitored for up to five years post-implantation.
Though the technique clearly needs to be perfected further, these early results are a promising leap forward for the field of reconstructive medicine.
“These are the steps we need to make to bring this technology to patients,” said Jos Malda, a biofabrication and regenerative medicine professor at Utrecht University, to New Scientist. “It’s quite an achievement.”