How a Boy Became the First to Beat Back Diabetes

BY Howard Markel  January 11, 2013 at 12:21 PM EST

In a regular column on the PBS NewsHour website, Dr. Howard Markel, director of the Center for the History of Medicine at the University of Michigan, will highlight the anniversary of a momentous event that continues to shape modern medicine.

On Jan. 11, 1922, a 14-year-old boy hovered between life and death. His name was Leonard Thompson and he was suffering the end stages of diabetes mellitus.

Leonard Thompson. Photo courtesy of Eli Lilly and Company Archives. Copyright Eli Lilly and Company. All Rights Reserved.

Because the only treatment available was a starvation diet, the boy weighed a mere 65 pounds when he was admitted to the Toronto General Hospital. Worse, Leonard was drifting in and out of a diabetic coma. His father was so desperate to save the boy that he agreed to let the doctors inject Leonard with a newly discovered wonder drug that had never been tried on another human being. The doctors called it insulin.

Insulin was discovered a year earlier by Frederick Banting, a tenacious, young surgeon from London, Ontario. During the fall of 1920, Dr. Banting became fascinated by studies on the role of the pancreas in regulating the metabolism of sugar and carbohydrates.

Soon enough, he hit upon the idea of ligating, or tying off, the pancreatic duct in order to isolate the gland’s “internal secretion,” a yet-to-be-identified biological substance which facilitated this critical metabolic process. Soon after, Banting took his idea to a world-renowned University of Toronto physiologist named J.J.R. Macleod.

Initially skeptical of the young surgeon’s idea, Macleod eventually and somewhat begrudgingly lent Banting a makeshift laboratory for his use during the summer of 1921. Macleod also provided some dogs for him to experiment upon and assigned an eager medical student named Charles Best to help Dr. Banting with the necessary chemical analyses.

C. H. Best and F. G. Banting ca. 1924. Photo courtesy of University of Toronto.

The results were nothing short of remarkable. By the summer’s end, Banting and Best were able to isolate an extract of pancreas from the pancreatic duct-ligated dogs and successfully use that crude extract to treat diabetic dogs, both in terms of normalizing their blood sugar levels and relieving their diabetic symptoms.

Upon return from his summer vacation in Scotland, Professor Macleod was so impressed by the results that he dedicated his entire research team, including a talented biochemist named J.B. Collip, to the purification and production of insulin, with the goal of using the life-giving substance on human patients suffering from diabetes. By the winter of 1921-1922, Banting and Best were presenting their results at prestigious medical conferences to great acclaim and excitement.

Alas, the first trial of insulin on a human was not terribly encouraging. Although the pancreatic extract lowered Leonard Thompson’s blood sugar by about 25 percent, the boy developed a severe allergic reaction to insulin. Consequently, the experiments were temporarily halted until a better means of purifying insulin could be developed.

Samples of insulin from the early days of the drug’s development. Photo by SSPL/Getty Images.

Two weeks later, on Jan. 23, 1922, Leonard underwent a second series of insulin injections and the results were stunning. His life was, literally, saved by insulin and he became the poster boy of the now commonplace medical miracle.

Banting and Best wrote these results up for the February 1922 issue of the Journal of Laboratory and Clinical Medicine. No stuffy medical paper, the discovery of insulin and its application to human beings made front-page news around the world.

By 1923, insulin was produced in seemingly unlimited quantities by the Eli Lilly Company of Indianapolis. It was a blockbuster drug of gargantuan proportions and a reprieve from certain death for tens of thousands of diabetics that year, and millions in the years since.

Later, in 1923, Banting and Macleod (but not Best or Collip) received the Nobel Prize for Medicine or Physiology. Banting magnanimously shared his prize money with Best; Macleod followed suit by sharing his prize money with Collip. Leonard lived another 13 years, thanks to insulin, before succumbing to pneumonia, most likely a complication of his diabetes, at the age of 27 in 1935.

Insulin opened the door for a series of discoveries on hormones and a slew of other “wonder drugs” that continue to improve and save the lives of billions of people around the world.

A quintessential Eureka moment of 20th century medical science, the discovery of insulin by a determined surgeon assisted by a mere medical student continues to inspire a legion of scientists working in 21st century laboratories. And it all began with a borrowed laboratory, a few experimental dogs, a desperate patient, and an inspired surgeon with an extremely good idea.

Dr. Howard Markel is the director of the Center for the History of Medicine and the George E. Wantz Distinguished Professor of the History of Medicine at the University of Michigan.

He is the author or editor of 10 books, including “Quarantine! East European Jewish Immigrants and the New York City Epidemics of 1892,” “When Germs Travel: Six Major Epidemics That Have Invaded America Since 1900 and the Fears They Have Unleashed” and “An Anatomy of Addiction: Sigmund Freud, William Halsted, and the Miracle Drug Cocaine.”

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