Lab-grown mini-lungs could reveal why covid-19 kills

Inside the biosafety level 4 lab at the National Emerging Infectious Diseases Laboratories (NEIDL) in Boston, researchers wear three sets of gloves and breathe air piped into moon suits through snaking tubes. Before them, under a plastic shield, are human lung-sac cells grown from organoids, blobs of cells that mimic organs.

Now it’s time to infect them with the coronavirus.

What happens next could shed light on the strange and deadly effects of covid-19—because it’s not just the virus that matters, but the body’s reaction to it. People are dying from that reaction, and organoids could help zero in on where the damage is worst. Accurate cell models are already pinpointing how the virus gets into the body, where it causes the most harm, and will help in the search for treatments.

Many virologists work with computer data, or with surrogate viruses into which they plug parts of the covid-19 germ, or sometimes by infecting supplies of monkey cells that viruses like to grow in. But these surrogates can’t tell you what the actual virus does to specific human cell types. “If you work with the real thing, you get real results,” says Elke Mühlberger, a microbiologist at NEIDL, which is operated by Boston University. “If you are interested in the host response, then substitutes are of no use.”

One area where research on lab-made human lung tissue could pay off is in testing covid-19 drugs. Before trying any potential antiviral drug on people, researchers test their potency at blocking the virus in the lab. But after years of adaptation to a petri dish, standard laboratory cells are far from normal. “They’ve lost their ability to act as lung or liver, they don’t respond to interferon—they are very different than the real thing,” Mühlberger says. “They don’t do much other than get infected.”

Cells from organoids are different.