Artificial Blood Vessels Grow On Nano-Template

Invisible Pink Unicorn writes "Researchers at MIT have found a way to induce cells to form parallel tube-like structures that could one day lead to tiny engineered blood vessels. The researchers found that they can control the cells' development by growing them on a surface with nano-scale patterning. The work focuses on vascular tissue, which includes capillaries, the tiniest blood vessels. The team has created a surface that can serve as a template to grow capillary tubes aligned in a specific direction. The cells, known as endothelial progenitor cells, not only elongate in the direction of the grooves, but also align themselves along the grooves. That results in a multicellular structure with defined edges — a band structure. Once the band structures form, the researchers apply a commonly used gel that induces cells to form three-dimensional tubes."

Re:More on this subject....

[Anonymous Coward]

goatse using the "I am lucky" feature through google...just warning you

a bunch of considerations

[anothergradstudent]

This is related to my work as a bioengineer, so I feel compelled to comment on it.

This is interesting stuff, basically using PDMS patterning to induce channels through which progenitor cells can be used to induce endothelial cell formation, and then they talk about using Matrigel (a collagen-based gel) with these blood vessels that form, but there are a bunch of "this can't be really used for anything" problems:

1) They used VEGF, which induces blood vessels everywhere you put it. So this is not really novel. There've been a ton of papers showing this. The problem with VEGF is that the vessels formed aren't really stable, and they don't last.

2) Your blood vessels, at least the larger ones, have a lot more structure than what they're indicating. You need smooth muscle cells and fibroblasts to form the rest of the vessel. They haven't done that here.

3) You still haven't really addressed the biocompatibility issue for implantation or any sort of real world implementation.

Robert Langer is considered by many to be a father of bioengineering, but that doesn't mean every paper he does is going to be awesome.

Better URL

[harvardslacker]

I don't know what the deal is with this story linking to 'Eurekalerts', but here's the link to the press release on MIT's news office's site:

http://web.mit.edu/newsoffice/2007/vascular-1217.html [mit.edu]

Greg

Re:The better question is: why?

[protobion]

So for example, you're not hard-coded to have X millimeter thick muscles, or a certain bone density, or exactly this pattern of capillaries. You're built to react to how much do you need.

While that may be correct in the sense that there are usually numerous feedbacks that regulate the nature of biological systems, there are several situations when average parameters such as the size of organs or density of tissues are merely a result of stochastic processes settling on some kind of local thermodynamic minima in terms of development.
For example, over-expression of human proteins in plants is possible [bbc.co.uk]. Hardly anyone will argue that the plants need it. They produce it only because the activity does not break the plants system.
More accurately , biology doesn't care what you need. Your particular biology is just one of many possible paths in a molecular or ecological parameter space - one of many paths that includes the organism "existing" for a duration of time that we call normal. Biology is what just works.