Courtesy Stevenfruitsmaak via Wikimedia CommonsWhen a cancer cell (a tumor) appears in a particular organ or area of a body, it somehow signals the body's immune system to back off and leave it alone. This allows the cancerous tumor to grow and eventually metastasize to the lymph nodes and other parts of the body. It's as if the cancer grants itself a sort of diplomatic immunity against the body's natural antibodies from interfering with its destructive undertakings.
Now, researchers have found a drug that switches off this "don't touch" warning and allows the cancer to be diminished or entirely destroyed. And it works for several types of cancers, including those affecting the brain, liver, colon, breast, ovary and prostate.
A protein called CD47 is present in human blood cells and prevents those cells from being attacked by the body's immune system. The protein attaches to the surface of the blood cells and signals to the immune system that the blood cells are "okay" and shouldn't be destroyed. About ten years ago, biologist Irving Weissman and researchers at Stanford University's School of Medicine noticed higher levels (up to 3x more) of the same "don't touch" protein were present in leukemia cells, a blood disorder. The surprised Weissman realized that the blood cancer was co-opting the body's own defense system to work against itself, thereby stopping any attacks on the cancer. This left the cancer unmolested and able to grow and spread. After further testing, Weissman and his colleagues subsequently discovered that CD47 levels in many other cancers were also higher than levels in normal cells.
"What we've shown is that CD47 isn't just important on leukemias and lymphomas, it's on every single human primary tumor that we tested.“
The Weissman lab has now developed a promising drug that switches off this "don't touch" signal in cancer cells giving the body's immune system the green light to go after them. The drug has been tested in the laboratory using petri dishes containing treated and untreated cancer molecules. Immune cells (macrophages) were present in each sample. In the untreated sample, the macrophages ignored the cancerous molecules, while they readily attacked those treated with the anti-CD47 drug. In later tests, a variety of human cancer tumors were placed into lab mice and left to grow for two weeks. After the tumors grabbed hold, they were treated with the anti-CD47 therapy and the tumors shrunk considerably or disappeared altogether.
"The microenvironment of a real tumor is quite a bit more complicated than the microenvironment of a transplanted tumor," Weissman said, "and it's possible that a real tumor has additional immune suppressing effects."
The biologist is confident that the research will eventually move into human clinical trials within the next two years.
The iStethoscope is apparently already replacing the real thing in hospitals. (I downloaded it for $0.99, but you're supposed to watch a tutorial to make it work. I didn't watch, I got it to work, and now I don't know what the tracings mean. Geez, why not just go to med school already?)
Meanwhile, the MIT Media Lab has invented a device to turn your smart phone into a portable optometry office.
Courtesy dfinnecyI don't think this is what Patsy Cline was singing about, but if you follow the link below you'll be able to arm yourself (pun intended) with what to do when unforeseen accidents separate you from your fingers, toes, teeth, etc., or even if your eyeball pops out.
Courtesy Nicolle Rager and National Science FoundationScience Buzz has had a lot of articles on organ transplants over the years but a new report on liver transplants in children adds a new twist. Currently, severe organ damage or failure requires an organ transplant, preferably one from a donor with a histocompatibility similar to the recipient. In the case of severe liver failure in children, there is often no time to wait for a compatible organ and an incompatible organ is used requiring patients to take anti-rejection drugs (immunosuppression) for the rest of their life. In fact, 70% of all liver transplants require anti-rejection drugs.
Fortunately, the liver is one organ that has the ability to regenerate itself, especially in very young patients. The child patient is given a small section of donated liver, enough to allow the body to function properly, while leaving a small portion of their own liver intact. Hopefully, after a few years, the patient’s original liver will begin to repair and regenerate itself. The doctor can than gradually reduce the quantity of anti-rejection drugs, causing the body to slowly attack and destroy the donated liver segment. Eventually the patient will be removed from anti-rejection drugs completely, have their own liver back, and no signs of the temporary donated liver.
The liver is unique in its regenerative properties; for humans, that is. In other animals, such as amphibians, entire limbs can regenerate. Scientists are researching the role proteins play in cell regeneration in hopes that stimulating certain proteins in other organs of the body will encourage them to regenerate like the liver can.
Courtesy PSUMark2006Since Science Buzz is about the only Minnesota information source that has not had an item in recent days about new Viking quarterback Brett Favre, I'm going to change that and post this video of Favre speaking about the mysteries of rotator cuff injuries, evidently something he's been dealing with a lot longer than anyone knew.
Courtesy nbonzeyIf you're one of those people who is easily grossed out, you might want to stop reading this post. Because what I'm about to tell you might make your stomach turn.
In an effort to help heal human wounds, medical researchers have been studying creepy, crawly, flesh-eating maggots. THE SAME wiggly critters that appear in your garbage can, on road kill, and any place where they can find dead meat or rotten food. In case you don't know the maggot life story, eventually these larvae grow-up to become flies, at which point they continue to hang out with garbage. It's not a pretty life, but they don't complain much.
So...what do maggots have to do with medicine?
Well, people have known for a long time that deep or difficult wounds (ulcers, burns, deep lacerations) heal much faster if you enlist maggots for a little help. In fact, hospitals even breed fly larvae (maggots!) so they can apply "maggot therapy" to wounds that would otherwise heal poorly. As gross as it sounds, this technique actually works well. The maggots eat the decaying tissue, preventing bacterial growth and helping to keep the wound "clean" so it can heal better.
Until recently, researchers were not exactly sure how these maggots did their miracle work on wounds, or how they could make maggot therapy more accessible. What they've discovered is that an enzyme produced by the maggots can itself help to remove decaying tissue. You can read more about it here.
This means that new bandages infused with maggot juice, or maggot ointment, might not be far from drugstore shelves. The enzyme appears to help heal wounds large and small, and with very few side effects. I wonder if upset stomach is one of them?
What do you think - would you buy a maggot-based product to help heal cuts and scrapes?
In 1991, President Bush signed an executive order that forbade the National Institutes for Health from funding research on embryonic stem cells beyond the 60 or so stem cell lines that already existed at the time. President Obama's order will allow scientists to use federal money to to do research on any stem cell lines, although government money still can't be used to generate new stem cell lines. (The creation of a stem cell line requires the destruction of a human embryo.)
More Buzz stories on stem cell research...
Microbiologists Dr. Ashley Haase and Patrick Schlievert announced their findings in the journal Nature. Haase has been studying the Human Immunodeficiency Virus (HIV) for more than 25 years. Schlievert is an expert in infectious diseases.
The prevention is relatively simple: an over-the-counter lubricating jelly is mixed with a common and inexpensive food additive known as glycerol monlaurate (GML) and applied to the sex organs of female laboratory monkeys. The test subjects were then exposed to the simian version of the virus (SIV). In all five cases the treated monkeys showed no signs of infection while untreated monkeys all became infected. (One treated subject later became infected although researchers aren’t sure exactly why. It may be she became infected after the study ended).
The new treatment shows promise in fighting the sexual transmission of the AIDS virus in women and could lead to prevention of the disease spreading in both sexes. Every day HIV infects more than 5000 people somewhere in the world, and in Africa women make up more than half the new cases.
HIV spreads through a person’s bloodstream by hijacking the host-body’s own immune cells activated to fight the infection. HIV transmission can take place through unprotected sexual contact with an infected person, or by the sharing of needles with someone who is HIV positive. A pregnant woman with HIV can sometimes infect her baby in utero, or during birth, or via breast-feeding. Infection via blood transfusion is less common now that most blood banks screen for the AIDS virus.
Schlievert warns that this is only a treatment to guard against further transmission of the virus responsible for AIDS (as well as other sexually transmitted diseases), not a cure for those already stricken with the disease.
Isn’t it remarkable that a compound of a common water-based personal lubricant and inexpensive (1 cent per dose) food additive found in ice cream and chewing gum could lead to a simple way of guarding against infection from this devastating disease?
An advisory panel to the FDA is recommending approval of the first US drug made with help from genetically engineered animals. GTC Biotherapeutics makes Atryn, an anti-clotting therapy, using a herd of 200 goats bred to express a human protein in their milk. The drug is meant to help people with hereditary antithrombin deficiency, a genetic disorder that causes blood clotting. Patients and their families want the drug approved and say studies show it's safe and effective. But other folks argue that there hasn't been enough safety testing around the use of transgenic animals. The final FDA decision is expected February 7.