This Germ Could Save Your Life

Or at least keep your teeth cavity-free. A growing chorus of medical researchers say our bacteria-killing zealotry is misguided. Instead of fighting bugs, they argue, we should train them to do our bidding and then set them loose in our bodies. The trouble is keeping them there

By Jessica Snyder Sachs Posted 01.31.2008 at 2:24 pm 10 Comments

THE TUMOR BUGS

In January 2002, doctors at the Mary Crowley Medical Research Center in Dallas began injecting a genetically modified breed of salmonella into three cancer patients with large, inoperable tumors that had failed to respond to radiation or chemotherapy. For reasons still poorly understood, salmonella proliferates inside malignancies, perhaps because cancerous tumors tend to remain beyond the reach of the immune system. This salmonella was special, though. A Yale University team led by microbiologist David Bermudes inserted an E. coli gene into the bacteria. The gene produced an enzyme that activates a highly noxious, tissue-destroying drug. “The beauty is that neither the enzyme nor the drug that it activates does anything toxic except in places where they end up together,” Bermudes explains. In other words, the system is engineered to be harmless outside a tumor but deadly inside it.

The 2002 pilot trial proved a success, in that the bioengineered salmonella delivered its enzyme payload, produced a modest shrinkage in tumor size, and did no harm to the three patients, but the trial was too small to make any claims of a cure. To move into larger, meaningful trials would require following in Hillman’s footsteps through a battery of federal regulatory review boards. That costs money. Even if the researchers received approval to go ahead, they would need to come up with the many millions of dollars needed to usher any potential cancer treatment through large-scale patient trials.

That investment would most likely come from Vion Pharmaceuticals, the Connecticut biotech firm that currently holds Bermudes’s patent on the tumor-busting salmonella. Vion has no plans to tackle the regulatory process in the near future, however, says Ivan King, Vion’s vice president for research and development. “As a small company, we cannot move many things forward at any one time,” he says. What’s needed, he believes, is interest from a larger pharmaceutical company with much deeper pockets—just the kind of company that has yet to show interest in highly experimental bioengineered bacteria.

Smart Bug: The salmonella bacterium [main and inset] thrives inside malignant tumors. By modifying these bacteria to produce a toxic enzyme, researchers hope to create a targeted cancer killer. Kwangshin Kim/Photo Researchers; Vem/Photo Researchers

THE NATURAL WAY

Meanwhile, some researchers are focusing on unmodified microbes that could benefit the body. These “probiotics” are sold in grocery and health-food stores, yet few of the numerous available products have been rigorously tested. One of the exceptions is Lactobacillus GG, or “Culturelle,” isolated in the 1980s by Sherwood Gorbach and Barry Goldin of Tufts University. Over the past two decades, Gorbach, Goldin and others have published 250 scientific papers on this strain’s disease-fighting effects. Studies suggest that the bug has an immune-calming effect that may ease some food allergies. But its one clear and proven benefit is to reduce a person’s risk of picking up one of the many nasty intestinal bugs that cause food poisoning, traveler’s diarrhea and antibiotic-induced gastroenteritis, which results when antibiotics kill off a person’s normal intestinal bacteria and a disease-causing invader moves in.

In Europe, where probiotics have long been popular, they have also been used to prevent chronic respiratory and ear infections. In the early 1990s, Swedish ear-nose-and-throat specialist Kristian Roos developed a throat spray containing a medley of throat bacteria that dramatically reduced the recurrence of chronic strep infections. A few years later, Roos developed a similar concoction that protected toddlers and preschoolers who were predisposed to ear infections.

Roos’s probiotics demonstrated their worth in small clinical trials. But they also illustrate the challenge of developing a natural probiotic into a medical therapeutic. A small clinical trial may be enough to put a health claim on a nutritional supplement sold over the counter. But Roos wants to see such cures in the hands of doctors, who would judiciously prescribe them to patients. To do that, he must prove that his probiotics work in the same kind of large, multimillion-dollar trials that have stymied Bermudes’s cancer-fighting GMO.
For that kind of money, Roos admits, investors are right to expect an ironclad patent to protect their investment. But that’s difficult to do with bacteria that occur naturally on and in the human body. “Even though we can patent our particular mixture of organisms, it would be easy for someone else to come along and put together something slightly different from the hundreds of protective strains found in people’s throats,” he explains. Without the assurance of some meaningful patent protection on his product, he has been unable to attract financial investors, and his treatments languish in a storage freezer.

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10 Comments

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ForrestGump

02/05/08 at 9:10 pm

“I honestly think people are more comfortable with the idea of nano-robots scurrying through their bodies than they are of deploying bacteria,” Thaler muses. “But when you think about it, you cultivate your lawn. You’d probably like to cultivate your internal landscape.”

Well said. After we can overcome the hurdles of human timidness toward the implementation of modified bacteria in our bodies, there seems to be an entirely open and new scope of research in terms of productive bacteria. Instead of trying to create new cures and treatments for age old problems, why not manipulate something already in existence and change harmful bacteria into helpful bacteria?

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txt

02/10/08 at 11:01 pm

i think people are more willing to adapt than you think i my self think this is a very posible option for the future.

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Czar

02/13/08 at 10:16 pm

Once we understand the bacteria or virus genome, we could even reprogram them to hunt down other bacteria or viruses such as Flesh eating bacteria and HIV viruses. they can have a set lifetime of only a few days and have their reproductive genes removed or replaced.

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AliveUD

03/06/08 at 2:33 pm

The solution to all of humankind's problems is undoubtedly a natural one. Sunlight, modified bacteria, and algae are our friends. I know it sounds utopian, but seriously, we just need to make nature work for us in a symbiotic way. True, it may mean altering nature through genetic manipulation; but the point is that it can be done.

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berne04

03/08/08 at 1:44 am

We have been talking in my Microbiology class about using viruses to carry the (gene manipulated) cure for diabetes; make the body produce it's own insulin again. This is the wave of the future for treatments. There is a huge potential benefit to gene therapy.

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svseigel

03/12/08 at 4:47 pm

I was an AP biology teacher In 1993. Back then I asked a friend who was a doctor if some gut microbe couldn't be engineered to deliver insulin. He laughed. He said the naturally occuring bacteria are too well adapted to share space with a suboptimal organism. I countered that we could start with a patient's own flora, but he said simply adding or deleting anything would render it suboptimal.

In 1997 we attended a lecture on genetic medicine at the Exploratorium in San Francisco, the doctor was very sharp and forward-thinking. He said these avenues are "interesting but beyond our reach at present."

In 1999 my wife graduated with a B.A. in microbiology and almost every honor her university confers. Her signature position was that we view microorganisms the wrong way--a very small percentage are pathogens, while a large number are symbiotes--that we need to learn to work with them. Anyway, I asked her to mention my idea to her faculty. When she did, she was ridiculed by the full professors, tolerated by the more recent Ph.D.s, and taken quite seriously by the M.S. level instructors and graduate students. I'm gratified that she stuck with it long enough for us to learn that tenure often seems to impair the mind!

Fast forward to 2008. People are actually talking about my idea; while her idea is far more important. This plethora of Antimicrobial products not only threatens our personal micro-biomes, but it also accelerates resistance. These products should be tightly controlled lest we really do produce superbugs: PATHOGENS!

It's great if we can get friendly bacteria to do good things for us; it's terrible if we end up killing them off every time we use soap, toothpaste, lotion or even drink water!

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Vamphyri

04/06/08 at 10:29 pm

Well, we do have one that eats oil spills then dies of hunger when the source is depleted... Sometimes there are some pretty cool successes.

Naturally our own bodies have bacteria that were not part of our makeup before that do all kinds of things symbiotically - not the least of which is digestion.

The concern is more like the problem in nature when a bacteria or virus gets in a mutated state that causes it to breed fast in a crowded environment and start causing disabilities and death. Don't think for an instant that a genetic 'bug' for good or ill will be the same for everyone, just like some people have large reactions to things like chicken pox and some people get killed by simple diseases on a wide scale.

Just some thoughts :)

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kardelen133 (not verified)

05/26/08 at 9:43 am

Hi all
in the words of homer simpson.... holy crap! or maybe just, crap. you work for popsci, folks... what in the *#@* was that? to begin with, how long did it take you to make the two custom length leather straps? more than five minutes, to be sure. how long did you have to look for a belt with a buckle that size? i have never seen a belt like that in my life. wait, i'm sorry, let's start with who in the *&^% would want to do this in the first place? let's assume that you are actually trying to come up with 5 minute projects that someone might want to attempt, and using that assumption lets assume that even one of you has a little pride in what they do. if either of those statements are true, the video i jsut whatched is either the result of complete indifference, or complete ignorance. if this is where my subscription dollars are going, please do a five minute project teaching me how to unsubscribe.
forum plastik cerrahi saç ekimi lazer epilasyon tüp bebek burun estetigi
thanks.

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godnews

05/27/08 at 4:02 pm

The concept of using what should kill to relieve sickining people by minor modification to the basics of such is very interresting. although it is very hard to understand by many people, but it is the basic truth.
العاب-العاب بنات-العاب تلبيس-العاب طبخ-صور-صور بنات-صور مضحكة
Thanks

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John.k

03/08/09 at 7:04 pm

I think we have a natural, existing, means to to fight tooth decay. I am 73 years old and I have no cavities. I am curious has anyone thought to find out why some people donot have cavities? I eat far too much sugar. I am not being treated with any anticavity agents, including flourides, which I think will be banned someday.

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