At a lab in Philadelphia’s Drexel University, a desktop 3-D printer is cranking out miniature samples of bones. In Toronto, another researcher is using the same printer to make living tumors for drug testing. It looks like an ordinary 3-D printer, but instead of plastic, it squirts out living cells.

BioBots, the startup behind the device, wants to change how researchers do biology. “We’ve been doing experiments on cells in a dish since 1905, and that’s still what we’re doing today to learn about how things work inside of our body,” says Danny Cabrera, CEO of BioBots. “But the body is a three-dimensional structure. Cells in our body are used to interacting with the world in 3-D. The fact that we’ve been doing biology in 2-D for over 100 years now is sort of limiting.”

In the past, the researcher with the 3-D printed tumors would have tested new tumor-fighting drugs in a dish or on an animal–neither of which really represents how the drug would actually work in the human body. The 3-D printed version gets much closer to the real thing. “It mimics the tumor micro-environment really well,” says Cabrera. “So when you pass drugs to it, it really is a much better predictor of what the effects of those drugs is going to be.”

The researcher studying bones is learning how bones form. “The vision is that once we understand these processes we can recreate them, and we can begin to engineer bones for people who need them,” he says. Other researchers have printed out samples of heart tissue, lungs, the brain, skin, and cartilage.

Farther in the future, the devices might be used to help patients get more individualized treatment–you might go to a lab, give a sample of your own cells, and then a researcher could print a miniature version of your own organs and test how you’d react to a particular drug.

While biofabrication–building fake structures out of living tissue–has been around for a while, existing machines were expensive (some running half a million dollars), huge, and out of reach for most researchers. “Only a small number of institutions had the ability to use them,” he says. “We set out to democratize that technology and to innovate build better tools.”

Other 3-D printers use UV radiation that can harm cells, so the startup pioneered a new process that uses visible light and avoids damage. They also radically changed the printer itself. “We designed a device that was much smaller and much easier to use and way less expensive,” Cabrera says.