Paolo Macchiarini and a research consortium from the Karolinska Institutet in Stockholm, Sweden have made a tissue engineered scaffold for the esophagus from esophagi that were extracted from rats.
After the cells were stripped from the rat esophagi, bone marrow mesenchymal stromal cells were seeded onto the decellularized esophagi and grown in a perfusion bioreactor. A variety of experiments demonstrated that these mesenchymal stromal cells differentiated into esophageal epithelial cells and smooth muscle cells. Macchiarini and his group used several gene expression and functional assays to confirm that these cells had in fact differentiated into these esophageal-specific cell types.
Next, Maccharini and others transplanted these esophagi into rats. The transplanted rats survived 14 days after the transplantations and ate and gain weight. Because the cells used to reconstitute the esophagi came from the rats into which they were transplanted, immunosuppressive drugs were neither used nor needed.
When the recipients of the transplanted esophagi were sacrificed after fourteen days, tissue examinations showed that all the major cell and tissue components of the esophagus including the inside covering of the esophagus (epithelium), muscle fibers, nerves, and blood vessels had nicely regenerated.
This successful bioproduction and transplantation of a tissue-engineered esophagus represents a significant step towards the clinical application of bioengineered esophagi.
Think of it: children and adults with tumors, congenital malformations of the esophagus of traumatic injuries to the esophagus may have new hope and possibilities because of advances in tissue engineering like this.