|MadSci Network: General Biology|
Thanks for your question, J.M. You've got the basic idea behind therapeutic cloning correct, but the approach currently being used in clinical trials is a little different. Instead of using cells produced as above(embryonic stem cells), a different kind of cell(multipotent stem/progenitor cells) are obtained directly from the bone marrow of the patient. This is done so that you don't have as many issues with immune rejection, and because these cells naturally encourage new blood vessel growth.
I don't know of any clinical trials in atherosclerosis directly, but I do know that progenitor cell transplantation is being studied for use in diabetic wound healing, in vascular graft repair, and in ischemic heart injury where the heart fails because one of the blood vessels feeding it becomes obstructed.
So new blood vessel generation is possible, as well as repair and remodeling of the existing damaged tissue. It's not certain whether the cells remain at the site of administration, or if they exert their effects by secreting stimulatory factors for a short time before getting cleared from the body, and would therefore require a new administration of cells each time. It's possible that a drug that mimics the effects of the stimulatory factors could be developed, however, the cells are secreting the factors slowly over a period of time in a certain area, whereas a drug would be systemically administered, so you'd want to make sure that your drug only acted upon the cells you wanted it to.
In any case, cells begin to die in hours if they lose their blood flow, whereas angiogenesis (new vessel growth) is a slow process, occurring over weeks to months, so you wouldn't want to use a drug to close the arteries of any tissue that you didn't want to die, however, this approach has been used to treat cancer.
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