3 replies to this topic

[rgvandewalker]

Somatic editing is an ultimate biomedical technology. Basically, it lets surgeons edit a recording of one's body in silico, and then assemble the result.

Somatic editing using molecular nanotechnology will probably have several phases: 1. Scan a body. 2. Edit the data. 3. Assemble cells. 4. Assemble a body from cells.

Since healthy, long-lived mammalian cells can now be cultured, fermentation can replace 3 for now. Machinery for 1, 2 & 4 seems grossly feasible, because we can already construct micromachinery with photolithography. When molecular nanotechnology becomes available, somatic assembly can only improve.

It seems like it can heal anything, including whole body freezing, and copy people in improved, more youthful cells. A person's recording is a back-up for them, a much-sought capability to mitigate accidental death. The biggest problem is that the best available scans are destructive.

Though ink-jets can't assemble arbitrary neural structures, cellular assembly and fusion to confluence have been grossly validated. [See http://www.missouri..../organprint.pdf]

I have a much larger document about pros, cons, feasibility, a verbal design with six-axis micromanipulators, a development path. and references, but I don't know where it put it. Long posts are hard to read. Any suggestions?

Edited by rgvandewalker, 01 January 2004 - 02:58 AM.

[kevin]

Hi rg..

I think your document on somatic editing got placed into your custom page.. check your profile to see if I'm right.. Do you have a link to it perhaps? You may have difficulty pasting HTML code into the messages as well which is what appears might have happened..

very interesting..

[Cyto]

Well, I've thought about it...and it intrigues me as to how this process will turn out.

Continuing on with the problem of encouraging angiogenesis though...

Such anti-angiogenic factors as Pigment Epithelium Derived Factor (PEDF) have been shown to be abundant in the retinal and neural/glial tissue. This factor can even ablate any vascularization in the presence of strong angiogeneic factors like FGF1 (fibroblast growth factors), FGF2, VEGF (vascular endothelial growth factor), and Interleukin-8. So for this to take place I would say smaller needles packed closer together, resort to switching out the tubes or flushing(said in PDF). As of now PEDF has no inhibitors known, except age and tumors. When some neural tumors were investigated they found pedf to be either deleted or mutated.

As for the how the machine could replicate the already established synapsi, I don't know. Each active site and post synaptic density has its own unique structure and receptor expression/maintenance. Don't know how you could replace that with 'new' neurons (and glia) when memory persistence would be affected.

(shrug)

Welcome to ImmInst.

[rgvandewalker]

Yes, I posted the raw HTML to my custom page. It's MS word-generated and therefore sort of twisted, but it displayed OK in my browser when I tested it. It should be possible to download it, extract the valid code, and see it with a good format. It'll be nested inside the stuff generated by ImmInst's relationship management software.

It has... a suggested mechanical design, some feasibility math, and references.

I'm not worried about angiogenic factors. Basically, the machine can build blood vessels wherever designers decide to put them. Something like that has already been done- see the paper http://www.missouri..../organprint.pdf

The only problem with that scheme was that the supporting gel was too weak to support the blood vessel against normal blood pressures. The obvious step is to try embedding the cells in a gel that's a stronger, more realistic extracellular matrix. My paper proposes a different method, but you know, only one scheme needs to work.

Scanning and neuroassembly is the big question-mark for me. I'm sure that some variation of a microassembler can perform neuroassembly. I think an organization with money should fund a team to try to scan and assemble some trained, very small transparent worms, (nematodes?) maybe scanning with a fluorescent confocal digital microscope (like Zeiss has) and assembling with a robotic Huxley-Wall micromanipulator (like Sutter has)

I think I (or most any good software engineer) could write the software to turn scan data into pick & place instructions for the manipulator, but real biologists have to be involved to figure out how to scan the worm, culture and mount the cells and synapses.

Figuring how to scan the synapses, then adjust the new synapses, or grow them, or whatever, is -exactly- the problem. Also, remember, perfect reproduction is not required. Most engineered systems work fine if they're within 5%. Natural neural nets can probably tolerate at least this much variation.