Bioengineering | Futurismic

Using salmonella to administer vaccines

Tom Marcinko @ 17-07-2008

A team of researchers has engineered a live form of salmonella that can deliver a vaccine. The modified bacterium eliminates all the things you don’t want in salmonella, the leading cause of food-borne illness. It’s also designed to destroy itself so that it’s not released into the environment. In the petri-dish experiment,� tame salmonella delivered a portion of S. pneumoniae bacterium to cells and stimulated an immune response.� Another possible benefit, if the technique works in animals and humans:

Unlike most vaccines that are entirely manufactured by a vaccine company, the attenuated recombinant salmonella vaccine after entry into the immunized individual serves as its own factory to produce (manufacture) the protective antigens (proteins) from the S. pneumoniae pathogen. This ability to cause manufacture in the immunized individual dramatically decreases the cost of such vaccines to make them affordable for use in the developing world, [Arizona State professor Roy] Curtiss said.

[Image: Salmonella invades human cells by Nutloaf]

Of Mice, Men, Women, Children, and Bacteria: Are Microbiota Linked to Obesity?

Tom Marcinko @ 18-06-2008

fatmouse This isn’t likely to let us off the hook for diet and exercise. But reseachers at Mayo Clinic Arizona and Arizona State University’s Biodesign Institute say the trillions of bacteria in your gut may play a role in regulating your weight. Mice that lack certain bugs tend to be fatter than their germ-free laboratory counterparts, and exposing lab mice to the germs makes them fatter. How much they eat, and how often they hit the exercise wheel, don’t seem to have an impact.

What about people? One study of children from birth to age 7 found:

The children who were normal weight at age 7 had distinctly different bacteria in their [stool] samples than those collected from overweight-obese children, suggesting that differences in the composition of the gut microbiota precede overweight-obesity.

The usual caveats apply: The bacteria/obesity connection has yet to be proved, and more research is needed before this leads to obesity treatments. SFnal scenarios about genetic engineering, nanotech, weight regulation, or gypsy curses are good to go.

[Illustration: deletem3]

Nanotechnology, bioengineering combine to make cheaper, better vaccines

Edward Willett @ 17-09-2007

So, for my first real post, how about some good news combining bioengineering and nanotechnology, making it very futurismic–er, futuristic. Whatever.

Researchers at the Ecole Polytechnique Fédérale de Lausanne in Switzerland have developed (and patented) a nanoparticle that, they believe, can deliver vaccines "more effectively, with fewer side effects, and at a fraction of the cost" of current vaccination methods.

Once upon a time, vaccines were made from dead-but-whole or living-but-weakened pathogens. Recently, researchers have figured out how to generate an immune response with a singe protein from a virus or bacterium. They’ve also discovered that the best way to get sustained immunity is to deliver an antigen directly to the specialized immune cells known as dendritic cells (DCs).

The trouble is, DCs aren’t all that common in skin or muscle, where injections are usually made, and in order to use them to activate the whole immune system, you also have to deliver a kind of "danger signal"–which there hasn’t been a good way to do, until now.

The new nanoparticles are so tiny they slip right through the skin and into the lymph nodes, where there are lots of DCs, and they carry a chemical coating that mimics the surface chemistry of bacterial cell walls. The result: a strong immune response without nasty side effects.

The researchers believe these nanoparticles could make it possible to vaccinate against diseases like hepatitis and malaria with a single injection, and at a cost of only a dollar a dose, far cheaper than current vaccines. The research team also plans to try using the technique to target cancer cells. And best of all, they say, the technique could be in use within five years. [Photo from Wikimedia Commons]

(Via Science Daily.)