There is only one man who has been cured from AIDS and this patient did suffer from leukemia. When he treated leukemia the patient did fortunately obtain a bone marrow transplant from a voluntary donor in Berlin and by astronomical coincidence, the donor was naturally immune to AIDS.
This means that if ever there is a natural mutation way to copy the function of blood cells and alter DNA, human beings could achieve complete immunity to various diseases.
Dr. Carl June and her colleagues at the University of Pennsylvania are trying to make genetic modification a safe possibility. A particular technique was used to try to interrupt gene in the T cells, a category of cells that is attacked by AIDS. The team has been re-introducing these cells in the body, to evaluate whether the cells will be able to enhance immune system and fight against the virus.
The effectiveness of the mechanism depends on natural agent known as zinc fingers. Some researchers are considering using zinc finger as a therapy against other diseases and pathologies such as hemophilia, bubble-boy disease as well as sickle-cell anemia.
Eventually the “Zinc Finger Technique” can practically work on chromosome of animals and plants. It can become a typical method to alleviate and cure various human pathologies. It could even be possible to change human eggs and sperms to avoid inheritable pathologies.
Zinc Fingers
Zinc Fingers are necessary chemical substances of protein that is present in living cells to activate and dis-activate genes. The name has been given based on the zinc atom that connects spheres of protein, to produce a “finger”. The finger identifies certain DNA sequences and controls proteins with precise initiation to target genes.
Advancement in the field of biology has enabled effective DNA recognition and modification of genes. Eventually, a normal zinc finger identifies various DNA molecules or a set of 3 letters. Moreover, by combining fingers together an artificial protein can be formed to suit other purposes.
“Sangamo BioScience, Inc” is the biotech company that has developed the innovative zinc finger technique with contribution of “Zinc Finger Consortium”. Moreover, “Aaron Klug” discovered the zinc finger design. He attributed to a potential approach to manipulate genetic structures. He constantly progressed in matching zinc fingers with various sequences of DNA letters.
The founder of Sangamo BioScience 1995, Edward O. Lanphier mentioned that “full alphabet of zinc fingers” is now available; however, it was complicated to find them. Now Zinc finger proteins are expected to have many different uses.
Practically, zinc fingers can be used similarly to word processing systems, whereby genetic text parts can be cut and paste. If two pairs of zinc fingers can be used to cut DNA, leaving DNA segregated within the two zinc fingers. The cells will thereafter rejuvenate. Moreover, the interference can be used to damage the gene and thus this would avoid receptor gene to allow AIDS virus to penetrate white blood cells.
Moreover, new genes can be entered into a cell in the segregated region (between two zinc fingers). This new gene can instigate cell repair. For instance, contemporary gene therapy approach utilizes a virus to penetrate cells. Yet it is impossible to assure that the new gene enter a precise location.
A biologist, J.Keith Joung, who designed zinc finger proteins, at Massachusetts General Hospital considered that it has allowed critical experiments. Moreover, a plant geneticist, Daniel F. Voytas, from University of Minnesota considered that zinc finger approach allows an astronomical range of changes to be made to all species of plants.
Using Zinc Finger Technology
Zinc Finger Technology has taken tremendous time to develop and design. It uses a meticulous precision allowing genomes to be cut at specific areas. Although Dr. Joung and Dr. Voytas at Zinc Finger Consortium are providing the method for-free, there are very few laboratories which are using it. The dedication and expertise required to make it right requires some 200 steps.
Yet, Sangamo has licensed “Sigma-Aldrich” to cut genomes for fee of $39,000. To cut more well typical genes the cost is around $12,000. In recent years Sigma-Aldrich has used zinc finger to produce rats with human diseases, for instance a rat with schizophrenia can be purchased for $100.
The president of Sigma-Aldrich’s biotechnology unit, David Smoller, licensed the Zinc Finger technique from Sangamo in 2006. The technology has proven extremely worthy. Moreover, Zinc Fingers technique has also been licensed by Sangamo to Dow Agroscience for the generation of new crop plants. The company does actually have 4 clinical trials in phase; two for amyotrophic lateral sclerosis and diabetic neuropathy.
Clinical Trial to Treat AIDS with Zinc Finger Technique
Sangamo in collaboration with University of Pennsylvania has begun clinical trials to treat AIDS.
Achieving Immunity to AIDS
AIDS virus can contaminate people who have a CCR5 receptor on their T cells, permitting the virus to penetrate the immune system. Moreover, many Europeans (around 10 percent) inherit a mutation that prevents CCR5 gene. If ever a person inherits two such preventive attributes the CCR5 receptor will not be present on T cells. AIDS virus will be unable to contaminate making these people exceedingly defiant to human immunodeficiency virus (H.I.V)
Clinical Trials to Treat AIDS
Using the Zinc Finger Technique, T cells are practically removed to enable the dis-activation of CCR5 receptors. The cells that have been treated are multiplied and afterward re-introduced to the patient. Apparently, in vitro experiment has shown that the modified cells survive better than the untreated ones, as they do not face AIDS virus attacks.
It is still uncertain whether zinc finger technique will work or not according to Dr. Katherine A. High, an expert from University of Pennsylvania. A pediatric geneticist, Dr. Matthew H. Porteus from University of Texas thinks that zinc finger will resolve various setbacks of gene therapy.
The Zinc Finger Technique is a something that stem cell researchers have been longing for. Stem cells that are extracted from patients do often require genetic modification. This is now possible.
A stem cell expert, Dr. Rudolf Jaenisch, from Whitehead Institute in Cambridge Mass, approved that three genes had been successfully separated in embryonic stem cells. According to him, the technology has not reached perfection. Zinc Finger that was provided by Sangamo technology did not always work perfectly. Yet, it remains a substantial advancement for embryonic stem cell research.
Beyond Limits
The Zinc Finger technique can practically allow science to make modification to germ line. Germ lines are responsible for generating sperm cells or eggs. A genetic alteration to those cells could end its immortality and the body cells might decease with the individual. However, the changes conducted would be inherited to other germ line. It is considered immoral and unethical to make such changes even if there are incontrovertible medical reasons. Changes to germ line would alter and restrict actual progress and lead us to a new avenue with uncertainty and dangers.
Researchers as well as scientists responded to the ethical dilemma by considering that zinc finger is still not up to the error-free level to allow accurate germ-line engineering. Yet, it might soon improve and become feasible to even germ line.
Moreover, germ lines of zebra fish as well as rats have already been changed with zinc finger scissors. Dr Porteus, says that there are not any reasons why zinc finger approach cannot be used to alter human germ line in the future. If one day germ line modification is morally accepted, this could be used to address cystic fibrosis that impinges on various tissues.
According to Dr. Porteus, zinc finger scissors could be used to correct the cystic fibrosis in unfertile eggs, yet society is not ready for such a step.
Reference:
1. Zinc Fingers Consortium
2. Sangamo
3. New Your Times
Anti Aging, Anti Aging Theories, Bioscience, Immortality, Nanotechnology, Stem cells
Tue, Jan 5, 2010
Anti Aging, Anti Aging Theories, Bioscience, Immortality, Nanotechnology, Stem cells