Patients with Type-1 diabetes don't have enough healthy islets of Langerhans cells — hormone-secreting cells of the pancreas. Granules inside these cells release insulin and other substances into the blood.
Steve Gschmeissner/Science Source
Carmen Smith now gets the insulin she needs via her doctor's prescription. When she lacked health insurance, buying a version of the medicine over the counter was cheaper, she says. But it was hard to get the dose right.
Lynn Ischay for NPR
A nurse in 1938 checks the amount of insulin in a needle. For many decades, the only insulin available to people with diabetes came from the pancreases of cattle or pigs. Insulin from animals is still available outside the U.S. — and cheaper than a recombinant DNA version.