Although we've seen "bio-inks" that allow sensors to be drawn directly on a person's skin and other surfaces to gauge things like glucose levels, functional inks such as this are usually heat-sensitive, meaning they aren't suitable for use in inkjet printers. Researchers at Tufts University have now developed silk-based inks containing bacteria-sensing agents that can withstand the rigors of inkjet printing, opening the door much wider for printing biomolecules.
Currently, recipients of arm or leg transplants need to take
immunosuppressive drugs for the rest of their lives, in order to keep
the donated parts from being rejected. If we could grow our own
replacement limbs, however, that wouldn't be necessary. And while we do
already possess the progenitor cells needed to grow such parts, what's
been lacking is a method of assembling them into the form of the desired
limb. Now, however, scientists have created a shortcut of sorts –
they've stripped the cells from one rat's forelimb and replaced them
with live cells from another rat, creating a functioning limb that the
second rat's immune system won't reject.