genetic heart engineering
Generic Heart Engineering:
One problem in the medical field is the rate of heart transplants compared with the number of them needed. The disparity is too great for the medical community and needs to be solved. The biggest contributor to this predicament is the fact that hearts must be taken from recently deceased people and cannot be taken from living, willing donors because that would basically be suicide. Also, another problem with heart transplants is, after the statistical miracle of receiving a new heart, the foreign tissue could be rejected by one's own immune system. In addition to this, the recipient must take a gamut of medications to combat this effect. So how could each of these problems be eradicated in one foul swoop? This could all be solved with the bioengineering of a generic heart.
First the term "bioengineering" must be defined. In my sense, this word means the manipulation of biology to yield good to man with the considerations of morals and ethics. With that in mind, I'm sure engineering a heart fits into this category because it: definitely has potential for human good; manipulates biology in a way that helps mankind; and is not beyond the ethics of today: none would stop the production of a beneficial product with the capability to save thousands of lives. Now that we have more insight into bioengineering, we can begin to discuss the engineering of a heart.
To engineer a heart, the pathways to its formation through stem cells must first be discovered through one genome line that is as healthy as possible (i.e. no signs of an genetic disorders, especially related to oncogenes, no family history of heart problems). Then a process could be made to grow a heart in vitro through the use of the right cell signaling, transcription factors and hormones. After this process is perfected, the genome could be screened again for any deleterious mutations that may have formed during this learning process. If any are to be found, then they could be excised through some method involving highly specific endonuclease (restriction factors) so only the specified site is affected. After this phase, the issue of foreign tissue rejection can be dealt with.
The issue that comes up with all transplanted tissues is foreign organ rejection. This problem arises from the body's specific immune system that can recognize "self" from "nonself." It does this through various immune system molecules like antibodies, macrophages, B-cells and T-cells. But each of these "finds" a "nonself" tissue through foreign surface molecules. The most important surface molecule in this process is called a MHC (Major Histocompatibility Complex). These are a sort of "I.D. card" that the immune system recognizes. These are highly variable in humans, so unrelated people usually have compatibility problems in transplants. But this can be changed with a few steps. If the strain of DNA used for developing hearts has its MHC gene or genes culled, then a patient could donate DNA so scientists could find, duplicate and insert the patient's MHC gene or genes. This would then allow scientist to grow hearts with the same specificity as the natural body. This then gives the medical community to simply grow you a heart, no matter who you are.
The one thing that must be stressed in this process is the genericness of its implementation. This process could be applied for any patient with heart problems. If your wondering why this doesn't already exist or why people aren't researching this it's because certain consequential procedures are missing.
One such barrier to the implementation of this heart growing process is the lack of knowledge about cell differentiation. The restrictions on embryonic stem cells must be lifted so the mechanics of this can be further understood. Also, the highly specific restriction factors must be made or a more efficacious method of DNA manipulation must be formulated. But there is hope for both of these vital links because researchers are working day in and day out to find information on both of these. But until we have every step of this process, eat healthy, exercise and treat your heart right.