Stories tagged antibodies

May
29
2007

Blood from bird flu survivors successfully treats H5N1 virus in mice.

Treatment for H5N1
Treatment for H5N1
The antibodies worked well when administered three days after the mice were infected, with all 20 mice in the treatment groups surviving, compared with none out of five in the control group. Antibody-producing white blood cells, called memory B cells, were separated from the blood of four Vietnamese who had recovered from H5N1 influenza (bird flu). In Switzerland, Dr. Lanzavecchia treated them with a process he developed so that they rapidly and continuously produced large amounts of antibody.

Next, researchers in Dr. Subbarao's lab screened 11,000 antibody-containing samples provided by the Swiss team and found a handful able to neutralize H5N1 influenza virus. Based on these results, Dr. Lanzavecchia purified the B cells and ultimately created four monoclonal antibodies (mAbs) that secrete H5N1-specific neutralizing antibodies." Science Daily

Human antibodies used in flu pandemic of 1918.

Using blood products from influenza survivors is an old idea, the researchers note. During the flu pandemic of 1918-19, for example, physicians took serum from recovered flu patients and gave it to new victims. A recent study suggests it halved the death rate, from 37% to 16%.

Antibodies are costlier and harder to mass produce.

The new antibody treatment could be used together with antivirals:

“What we are trying to do is add another arrow to the quiver of options for treating patients with H5N1 infection," says Cameron Simmons, who led the study. New Scientist

Because the survival rate was excellent even when treatment was delayed for three days, this antibody treatment would work well in treating the few people who catch the disease directly from birds, and for localized outbreaks. For large scale prevention against bird flu, antiviral drugs such as Tamiflu are the still the best defense.

Research article in PLoS Medicine: Prophylactic and Therapeutic Efficacy of Human Monoclonal Antibodies against H5N1 Influenza.

Apr
13
2007

Two years ago, everyone was talking about the work of paleontologist Mary Schweitzer: she noticed that thin slices of a 68-million-year-old fossil femur from a Tyrannosaurus rex looked like they still contained soft tissue. (See photos of the bone.) Using antibodies to the collagen protein, she showed that the bone still contained intact collagen molecules—the main component of cartilage, ligaments, and tendons.

Hello, dinos?: A new study shows that preserved collagen from a 68-million-year-old Tyrannosaurus rex is similar to that of chickens. (Photo courtesy Danelle Sheree)
Hello, dinos?: A new study shows that preserved collagen from a 68-million-year-old Tyrannosaurus rex is similar to that of chickens. (Photo courtesy Danelle Sheree)

She used antibodies to a type of collagen extracted from chickens. The fact that the antibodies stuck suggested that T. rex collagen is similar to that of birds. And when she compared the preserved soft tissue to that of modern animals, the closest match was an emu—a flightless bird.

To learn more about the collagen in the T. rex bones, Schweitzer worked with John Asara, a chemist at Harvard University, to analyze it using mass spectrometry.

The Economist describes the technique this way:

This technique identifies molecules (or fragments of molecules) from a combination of their weight and their electric charges. Knowing the weights of different sorts of atoms (and of groups of atoms that show up regularly in larger molecules, such as the 20 different amino acids from which proteins are assembled) it is usually possible to piece together fragments to form the profile of an entire protein.

When Asara compared the profile he'd created to proteins from living animals, the closest matches were to chickens and ostriches. (Schweitzer and Asara's study was published in the April 13, 2007, issue of the journal Science.)

Many paleontologists already believed, based on fossil bones, that birds are dinosaurs or their descendants. But this new paper provides even more evidence of the fact.

Buzz stories on the subject from last year:

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