Another fully lab grown organ transplanted: trachea, Sweden.

Surgery marks the first time a trachea grown from a patient’s stem cells and seeded onto a synthetic, rather than a donor, structure has been transplanted in a human.

What other organs have been made in the lab?

At this point, there are four levels of complexity.

1. The first level are the flat structures, like skin.

2. The next level of complexity are tubular structures, like the blood vessel, the windpipe

3. Next are hollow non-tubular organs like the bladder or stomach

4. The most complex are the solid organs like the heart

At this point, we’ve been able to do all the first three:

The fourth level– that’s going to take time – that’s still years away.

There are definitely more in the pipeline. At our institute - Karolinska, Sweden - we’re working at over 30 different tissue and organ types.

Biggest challenges right now, for any solid organ, is basically the vascularity, the blood vessel supply.

Stem cells: Windpipe transplant joins bladder, urethra artificial organs - Los Angeles Times