P.C. Shannon

An organism’s metabolome is all of its metabolites and metabolic processes—in other words, all of the chemicals that come out of it (like urea, carbon dioxide, and progesterone) and all of the biochemical reactions that produce those compounds. It’s one of those words that scientists concocted out of thin air because they fancy themselves clever lexicographers. But it’s a powerful concept and one of the keys to the future of personalized medicine.

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Researchers at MIT and the University of Hong Kong describe how peptides can self-assemble to control bleeding from surgical wounds. From Nature Nanotechnology:

The key to the success of this particular peptide is that it is water soluble and can be easily delivered by a syringe. Furthermore, self-assembly of the peptides is triggered by the ionic environment of the blood, and when broken down, the amino acid building blocks of the hydrogel can be used by the body to repair the injury.

This a great advance, thanks to nanotechnology. It can save lives on the battlefield or in accidents by stopping bleeding before the wounded are transported to the hospital. I think the other important thing here is that this is a clever application of biology rather than some sort of micromechanical approach. I think I’ve said this before—I think a lot of the important nanotech innovations are going to come from adapting biology, which already operates on the nanoscale, rather than trying to scale down macroscale machines. This is one example of that.

Listen people, the avian flu is coming. Hopefully later rather than sooner, but there will be a pandemic. And it’s gonna be bad. I’m not going to scare you with apocalyptic predictions, but please, get a flu shot.

As far as anyone can remember, I personally have only ever had the flu once. Never had it as a kid, never got it in college, even when my roommate in the dorm did. I finally caught it in New York City at the end of 2003. Caroline got it too, which was surprising because she’d had her flu shot that year. The injection only protects you against the three most common strains from the previous year, and that year, a strain of influenza called Fujian was very common. Still, the shot provides some generalized protection against all types of flu, so Caroline had a slightly better time of it than I did.

As a microbiology student in college, I realized that one possible reason that I never got in flu in spite of obvious exposure was that I had a mutation that made me immune. In a large enough population, there are always individuals with a natural immunity to a given disease; there are some people in the world who are immune to HIV, for example.

I also knew the particulars of influenza mutation and evolution. I won’t go into the specifics, but suffice it to say that influenza mutates and evolves rapidly, so that different strains appear every year and every few decades theres a pandemic. This means that if I had a natural immunity (and not just good luck), it wouldn’t protect me forever. The fear in the back of my mind is that when the next pandemic came, my mutation would make me hypersensitive to the virus, sealing my fate.

Now, my theory of natural immunity turns out to be true. A recent article in the journal PLoS Biology (technical article and general audience synopsis; I love PLoS, but that’s a subject for a different time) examined the genes of a number of flu viruses collected in New York State, including the so-called Fujian strain. Fujian just so happens to have certain mutations that make it different from the more common types of influenza, hence the epidemic of the 2003-2004 flu season.

These mutations also, apparently, allow it to overcome my natural immunity. The mutations obviously contribute to the strains increased pathogenicity. The bug that causes the coming pandemic is likely to have similar mutations as well as being ferociously virulent. Clearly, it has my name on it.

Really, its an emotional reaction to think that my mutation, which has so far granted me immunity, would work to my detriment when the avian flu strikes. Logically, I would be no more or less susceptible than anyone else. On the other hand, my body has only ever had to fight off one influenza virus, and that lack of general flu antibodies might work against me.

Hmm… When do flu shots start?