Shaping Life In the Lab

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with bacterially produced interferon, developed at Genentech. Interferon is part of a natural defense system against such viral diseases as influenza and hepatitis; it also seems to act against certain types of cancer, particularly cancer of the breast and the lymph nodes. But to date only extremely small quantities of it have been available, all painstakingly collected from blood cells and other human tissue. Relatively few patients, only several hundred out of the hundreds of thousands of cancer victims who might benefit from interferon, have been receiving the drug. Natural interferon is very costly (up to $150 for a daily injection). Most of the people getting it receive extremely small doses—perhaps too small to work. The object of the Texas experiment: to determine whether bacterially manufactured interferon acts any different from the natural stuff. If the synthetic drug lives up to its billing and causes no harmful reactions, bacterial assembly lines could start producing human interferon in wholesale quantities. The price might then come down to $1 a shot.

Another scarce drug now bubbling out of Genentech's stainless-steel fermentation vat is human growth hormone, used to treat dwarfism. Only limited quantities have been available, most of it extracted from the pituitary glands of cadavers. In a test of the hormone, 20 youngsters are currently getting doses of bacterially produced HGH at London's Great Ormond Street Hospital for Sick Children.

Genetically engineered microorganisms are also producing the enzyme urokinase, used to dissolve blood clots; the hormone thymosin alpha1, which shows promise as a treatment for brain and lung cancer; and beta-endorphin, one of the brain's own painkillers.

The drug closest to commercial production by gene-splicing techniques is insulin, the hormone that enables the body to burn sugar for energy. Last December a Derby, Kans., housewife, Sandy Athertone, 37, became the first diabetic to be injected with bacterially made insulin. It came from the pharmaceutical labs of Eli Lilly, which is spending $40 million to build plants in Indianapolis and outside Liverpool, England, to make human insulin by means of recombinant DNA. More recently other diabetics began receiving bacterial insulin in a test program in six U.S. cities. Lilly plans similar trials in Canada and Europe. Says one participating doctor, Fred Whitehouse of Detroit's Henry Ford Hospital: "So far the synthetic insulin appears to be as effective as animal insulin."

Lilly and other drug makers can easily meet current demand for insulin by extracting it from the pancreases of cows and pigs. The trouble is that of all diabetics on insulin—some 1.8 million people in the U.S. alone—5% suffer allergic reactions to the animal hormone because it differs ever so slightly from the human variety. It may also cause some of the circulatory problems associated with diabetes. By contrast, virtually every atom of the bacterial product is identical to insulin made in the body, and so should produce few reactions.

There is, of course, nothing new in harnessing bacteria for human good. Microorganisms have long been used, even if unwittingly, to serve man's needs, from breaking down wastes to making alcohol and producing antibiotics. Man began interfering with the genes, at least indirectly, long before the 19th century