I think most cryobiologists are going about it the wrong way, trying to get incrementally better at cryopreserving tissue. The work I’m aware of that seems most promising (I say, having almost no familiarity with the field) is Ken Storey’s work with wood frogs. They can freeze and thaw naturally.
I looked into it because I hoped I might be able to move some genes from a wood frog into a mouse, freeze it, thaw it later, and win the Methuselah Mouse prize. But it turns out that the frog has an anti-dessicant response to protect tissue from lack of water, an anti-ischemia response to protect tissue from lack of oxygen, a glucose response to produce glucose as a cryoprotectant, an anti-glucose response to protect cells from the huge amounts of glucose, and a bunch of other mysterious responses. It involves hundreds of genes. It’s going to take a large program to import entire gene pathways from one organism to another.
The wood frog mechanism is very different from the proposal of cryonics proper, which is vitrification (not freezing, at least under ideal conditions) and subsequent repair or uploading. Cryonics involves much lower temperatures than a wood frog could possibly survive at under natural conditions. Unsurprisingly, Ken Storey is a major cryonics skeptic.
On the other hand, the use of ice-blocking polymers in vitrification is analogous to antifreeze proteins used in biology. This reduces the concentration of penetrating cryoprotectants needed to achieve vitrification at the glass transition temperature, which in turn reduces toxicity.
My thought as to how gene therapy could be useful is that if you could have ice-blocking proteins or cryoprotectant sugars present inside of the cells to begin with, lower concentrations still could be used, implying less time at high temperature where toxicity can occur. Removal of cryoprotectants during thawing is a major problem which this would also help with.
Optimistically, this would lead to a revivable brain and/or cryogenic banking of other individual organs. I think whole body will be a lot harder than brain only, perhaps dramatically so. It may be better to work on robotic and biological life support technologies to permit the brain to survive on its own if we want to see a person or mammal actually making the trip both ways within our lifetimes.
Haha. Creative thinking, but I’m not sure if that would count as life extension by the rules of the M-Prize.
It would have been stupendously trivial if all one had to do is to copy-paste some genes into a mouse egg, or do some gene-therapy, in order to become freeze-resistant. Aubrey’s beard would go white in an instant.
Wow, that really stirs up the rebel in me.
I’m curious now to look more into the state of the art in cryopreservation. How close are we to successfully cryopreserving an organ?
I think most cryobiologists are going about it the wrong way, trying to get incrementally better at cryopreserving tissue. The work I’m aware of that seems most promising (I say, having almost no familiarity with the field) is Ken Storey’s work with wood frogs. They can freeze and thaw naturally.
I looked into it because I hoped I might be able to move some genes from a wood frog into a mouse, freeze it, thaw it later, and win the Methuselah Mouse prize. But it turns out that the frog has an anti-dessicant response to protect tissue from lack of water, an anti-ischemia response to protect tissue from lack of oxygen, a glucose response to produce glucose as a cryoprotectant, an anti-glucose response to protect cells from the huge amounts of glucose, and a bunch of other mysterious responses. It involves hundreds of genes. It’s going to take a large program to import entire gene pathways from one organism to another.
The wood frog mechanism is very different from the proposal of cryonics proper, which is vitrification (not freezing, at least under ideal conditions) and subsequent repair or uploading. Cryonics involves much lower temperatures than a wood frog could possibly survive at under natural conditions. Unsurprisingly, Ken Storey is a major cryonics skeptic.
On the other hand, the use of ice-blocking polymers in vitrification is analogous to antifreeze proteins used in biology. This reduces the concentration of penetrating cryoprotectants needed to achieve vitrification at the glass transition temperature, which in turn reduces toxicity.
My thought as to how gene therapy could be useful is that if you could have ice-blocking proteins or cryoprotectant sugars present inside of the cells to begin with, lower concentrations still could be used, implying less time at high temperature where toxicity can occur. Removal of cryoprotectants during thawing is a major problem which this would also help with.
Optimistically, this would lead to a revivable brain and/or cryogenic banking of other individual organs. I think whole body will be a lot harder than brain only, perhaps dramatically so. It may be better to work on robotic and biological life support technologies to permit the brain to survive on its own if we want to see a person or mammal actually making the trip both ways within our lifetimes.
Haha. Creative thinking, but I’m not sure if that would count as life extension by the rules of the M-Prize.
It would have been stupendously trivial if all one had to do is to copy-paste some genes into a mouse egg, or do some gene-therapy, in order to become freeze-resistant. Aubrey’s beard would go white in an instant.
Done, though not at LN2 temperatures:
http://www.ncbi.nlm.nih.gov/pubmed/15094092
http://www.cryostasis.com/perspectivesandadvances.pdf
Awesome. Thanks for the links.