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One of the major demands the world has always had is for newer, more effective medicine and treatments.  Many new discoveries in medicine have lead to newer drugs and antibodies that will vastly improve people’s quality of life.  Needless to say, there is both a global demand for an ability to create a better cure for diseases as well as many uncertainties about how some diseases work on a more detailed level.

There are many studies and areas of human medicine one could focus on and search for improvement over current standards, but one recent discovery in particular highlights potential on a relatively unexplored area of medicine.  This is the folic acid discovery found that the “…vitamin folate appears to promote healing in damaged rat spinal cord tissue by triggering a change in DNA.”

Folic acid, folate’s synthetic form, has been used as a way to promote spinal injury in the past. However, it is just until recently that it was discovered that it was folate that was the source of the healing process.  Nor was it recently known ‘how’ the folic acid worked, it was simply known that it had this effect and used accordingly.  The folic acid study it is known that it works by a process of, “injured nerve tissue began producing surface receptors for folate…and then is absorbed into the nerve cell” which triggered the accelerated healing of the spinal cord.

The maximum effect of Folic acid on accelerating the healing process does have a limit, which is 80 micrograms folate per kilogram of body weight.  After this point, the effectiveness of folic acid decreases but without causing toxicity or nerve damage.  This is good, as it offers a method to make the body naturally accelerate its own healing process, with no harm beyond normal healing rates if too much is taken.

The major niche in this discovery is part of what could be a revolution of modern medicine, the discovering and application of epigenetics, which are “changing the functioning of DNA without changing the composition of genes.”  Medicine previously would have to alter the genes to make the DNA function differently, so this newer way would pose much less risk to the taker than previous forms.  Such discoveries puts mankind closer to “…exciting new prospects for understanding the origins of disease and for developing new treatments.”

This discovery puts the intake of Folate for someone injured at an amount higher than the recommended daily allowance.  For a healthy person without a spinal injury, the U.S. RDA for folate is 400 micrograms per day.  For a person weighing 75kg (165 pounds) and a spinal injury, the ideal intake of folate would be 6000 micrograms per day; 15 times the daily recommended amount.

With the ability to use such epigenetic knowledge to trigger the body to fix itself without foreign help, simply natural or synthetic triggers, medicine could become harmless if unnecessary and possibly more effective than those we possess now.  One could make a fortune and add years onto the average lifespan of people around the world, promoting both the product and a healthier labor force to draw labor from.  There will always be a need for cures to injuries to parts that like the spine, as well as the brain, kidneys, etc. which a different vitamin could trigger.  Any cure or better method to heal currently permanent or chronic problems, such as Alzheimer’s or Parkinson’s, would be worth billions of dollars for a daily supplement that can reverse and then prevent such horrible diseases.  There would also be a fortune in being able to discover and map the different reactions of vitamins and synthetics to human genomes.

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Patenting the Human Genome

There are currently patents for 20% of the human genome.  Almost half of known cancer genes have been patented (Scientific American).

The DNA Patent Database is available to the general public, and provides the full-text of patents at no cost.

Background

A landmark case in the genome project was Amgen vs Genetics Institute in the 1980s.  Amgen claimed the DNA sequence used to invent erythropoietin, used to form red blood cells.  The case ruled in favor of Amgen, saying that the DNA sequence had to be included in the patent claim to secure intellectual property rights.  The first gene patented was that of erythropoietin.

In 2000 the American College of Medical Genetics and the College of American Pathologists objected to genetic patents at the 2000 AMA Annual Meeting.  They said that genes are naturally occurring, so they cannot be patentable.  This is correct– naturally occurring substances are not patentable.  However, the AMA said naturally occurring substances that are isolated from nature or manipulated may be patentable, which includes naked DNA.

Patent holders have the ability to prevent others from making or using their invention, but full disclosure of the invention is required to obtain a patent (AMA).  The current term of a new patent is 20 years from the application filing date, and after 18 months of filing the application enters public domain.

Guidelines

The United States Patent and Trademark Office (PTO) issued guidelines in January 2001 for genetic patents.  Patents for genes can be filed only if a specific and credible use was demonstrated.  These guidelines have made it clear that genes can be patented.  Although many people raised objections about genetic patenting, the PTO rejected the notion because “a gene may be removed from a person, then a clone of that gene may be made in a machine, which is then not a part of nature, but a product of the lab.” (AMA).

Since the 2001 guideline requiring that patents have “a specific and substantial utility”, there have been a substantial decline in the number of patents being sought (Scientific American).

Ethics and Concerns

The AMA Code of Medical Ethics has this to say about patenting human genes:  “A patent grants the holder the right, for a limited amount of time, to prevent others from commercializing his or her inventions.  At the same time, the patent system is designed to foster information sharing.  Full disclosure of the invention—enabling another trained in the art to replicate it—is necessary to obtain a patent.  Patenting is also through to encourage private investment into research.”  As for the notion that genetic patents are an attempt to own human life, the AMA Code of Ethics says that DNA sequences are not the same as human life, and that much is to be gained in the form of new medical therapies.

A February 2010 panel of the U.S. Secretary’s Advisory Committee on Genetics, Health and Society wants patents on diagnostic genes to cease (New Scientist).  The panel found that non-patented genetic tests (such as Huntington’s disease, cystic fibrosis, and colorectal cancer) were more available than patented tests (such as breast cancer, patent owned by Myriad).  The committee said that doctors providing diagnostic gene tests shouldn’t face the threat of being sued by companies owning patents to those genes.  The Biotechnology Industry Organization objects to this recommendation, saying that it will deter investors from funding new therapies.

Both Canada and Europe have rejected patents that the United States has accepted, including one of a gene causing cancer in a mouse (New Scientist).  Canada said the mouse was a higher life form than a mere “composition of matter”, and Europe narrowly allowed the cancer mouse patent but excluded all other rodents.

The End of Patents?

A 2006 article published in the Scientific American says that patent holders of diagnostic genes “have inhibited both research and clinical medicine.”  The Myriad company that owns the breast cancer genes BRCA1 and BRCA2 has “used its patents to stop major cancer centers from devising inexpensive ‘home-brew’ tests” for those genes.  Europe successfully challenged some of Myriad’s patients.  The test for breast cancer genes is now free in Europe except for Ashkenazi Jewish women, who must pay Myriad licensing fees since Myriad patents still cover mutations found in that population.  Therefore, a physician in Europe must ask a woman if she is an Ashkenazi Jew by law before testing her genes for breast cancer.

A March 29, 2010 ruling in the U.S. District Court for the Southern District of New York found that genetic patents “violated long-standing precedents barring the patentability of natural phenomena, saying the DNA over which Myriad Genetics Inc. claimed a monopoly represented ‘the physical embodiment of laws of nature’.” (AMA) The specific genes in this case included those of hereditary breast and ovarian cancer.  This ruling is believed to be the first of its kind. The case will probably be appealed, especially by those who say that the patent system is needed to attract investors to fund new research.

Opponents of genetic patents are claiming a major victory, saying that organized medicine will now have broader research and more accessible treatments.  Bruce Korf, MD, PhD, president of the American College of Medical Genetics was a plaintiff in the case.  He said, “Looking at genetic reports was like looking at a CIA document, where areas were blacked out because somebody owned them, and doctors couldn’t report the medical significance.  Now we’re not going to be bumping into those areas claimed as property by someone else, and the innovation we are looking for could further more efficient ways of doing genetic testing.”

While most people involved believe that patents can be helpful for innovations, the patent in this case was overly broad, creating a monopoly “that hampered scientific discovery and medical care,” according to American Medical Association President J. James Rohack, MD.

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Clinical Trials and Your Safety

The National Institute of Health (NIH) defines a clinical trial as a biomedical or behavioral research study of human subjects designed to answer specific questions about biomedical or behavioral interventions (drugs, treatments, and devices.)

The FDA and the Office of Human Research Protection (OHRP) regulate clinical trials.  An Institutional Review Board (IRB) reviews study-related documents, including protocols, informed consent forms, and physicians’ credentials.  Clinical trials must past a vast number of examinations before they are allowed to commence, which lessens the chance of adverse effects.

Informed Consent

Informed consent must include diagnosis of the patient’s condition, nature and purpose of the proposed treatment, risks and consequence of the treatment, probability of success, feasible alternatives, discussion of confidentiality, prognosis if treatment is not given, and a statement that participation is voluntary and may be discontinued at any time.  Informed consent must be written in a language understood by the subject, and must be provided in writing.

According to the NIH, “Generally, today, regulatory requirements for informed consent in federally-funded and FDA-regulated research overlap with the elements for a legally effective consent.”

Unfortunately, some research has shown that the informed consent process is flawed.  For example, studies have found that some participants are not aware they are involved in a research study, and many did not understand the informed consent form they signed.  Another flaw in the system is when physicians recruit their ill patients for a research study, who in turn believe that the treatment will be a definite benefit to them.

FDA Regulations

In order to have a clinical trial, the FDA mandates that good clinical practices (GCP) and adequate human subject protection (HSP) be provided.  Some regulations of GCP include electronic records, informed consent, financial disclosure by clinical investigators, and premarket approval of medical devices.

The Office of Good Clinical Practice is a part of the FDA.  Its functions include leading the FDA’s Human Subject Protection/Bioresearch monitoring Council and assisting the Commissioner on GCP and HSP issues arising in clinical trials.

The FDA website also has a section on “Reporting Complaints,” and has separate phone and fax numbers for biological studies, drug studies, and medical device studies.

The Office for Human Research Protections (OHRP), a part of the Department of Health & Human Services, reviews compliance with federal regulations of human subject protection in research done by the DHHS.

The DHHS has a department called the Office of Research Integrity, which handles research misconduct and regulation.

Institutional Review Board

An Institutional Review Board (IRB) is mandatory under the FDA for every clinical trial.  The IRB approves the protocol for the clinical trial and periodically reviews it to ensure human rights and welfare are being protected.  The IRB reviews the informed consent documents and brochures of the clinical trial, and may make clinical site visits to determine if the studies are in compliance with regulatory requirements.  However it is important to note that the FDA does not address IRB liability in the case of malpractice suits.

The FDA and Department of Health and Human Services regulate the structure and duties of IRBs.  For example, “each IRB must be composed of at least five members with diverse cultural and ethnic backgrounds, and both men and women should be included.”  At least one member must have a principal concern of science, and at least one member should have a nonscientific expertise.  IRBs must monitor the trial at least once a year, or more if the risks are severe.

The IRB must ensure 1) risks to participants are minimized; 2) risks to participants are reasonable in light of anticipated benefits; and 3) selection of participants is equitable.

State Regulation

About fifteen states now have state regulation of clinical trials, requiring registration and disclosure of the trials.  Maine has also adopted two laws regarding pharmaceutical research that prohibits pharmaceutical companies from advertising their drugs unless they have disclosed clinical trial information to the state health department.

Conclusion

In order to be given the “green light” by the FDA, companies wanting to run clinical trials must provide data saying the product’s benefits intend to outweigh potential adverse results, and that good clinical practices will be in place.  However not all trials result in a new drug or treatment, as some clinical trials do not demonstrate a positive reaction.  Even fewer studies result in harm to the human subject, but the informed consent clause usually protects pharmaceutical companies in that case.  Federal and State regulations are in place, and are continuing to be implemented, to lessen negative effects of clinical trials.

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Antimicrobial Resistance

Microbes cause disease, and include bacteria, viruses, fungi, and parasites.  In the last century great strides in medicine were made in combating diseases caused by microbes.  Antimicrobials have increased human life expectancy and decreased the ability of microbes to cause disease.  Disease conditions that used to be fatal are now easily treated with antimicrobials.

Unfortunately a new trend has reared its ugly head:  the microbes are fighting back.  Because they can easily mutate, reproduce, and pass on new anti-microbial genes to the next generation, microbial resistance has become a problem.  Many of the causes are due to our use and overuse of antimicrobials.

According to the World Health Organization (WHO), “The bacterial infections which contribute most to human diseases are also those in which emerging and microbial resistance is most evident:  diarrhoeal diseases, respiratory tract infections, meningitis, sexually transmitted infections, and hospital-acquired infections.”

The FDA’s Center for Veterinary Medicine provides this nine-minute video explaining the mechanisms of antibiotic resistance.

Causes

When microbes are fought with microbial agents, they must either adapt a method of resistance (“selective pressure”) or die. Those that are able to survive have genes for resistance, and pass these genes on to microbes near them (“conjugation”) or by reproduction.

Although developing a resistance to antimicrobials is a natural phenomenon, humans are often guilty of amplifying or accelerating the process.  For example, “when antimicrobials are used incorrectly—for too short a time, at too low a dose, at inadequate potency; or for the wrong disease—the likelihood that bacteria and other microbes will adapt and replicate rather than be killed is greatly enhanced” (WHO).

The WHO lists these trends that increased infections and allowed a misuse of antimicrobials:

  1. Urbanization causing overcrowding and poor sanitation, which has increased diseases like typhoid, tuberculosis, respiratory infections, and pneumonia;
  2. Pollution, environmental degradation, and changing weather patterns, causing malaria and other diseases spread by insects;
  3. Demographic changes, including a growing elderly population, increasing hospital-acquired infections;
  4. The AIDS epidemic, which has increased the number of immunocompromised patients and many infections (which were previously rare)
  5. The resurgence of old foes (malaria and tuberculosis), due to misplaced confidence that they were conquered, but are now responsible for millions of infections a year
  6. The growth of global trade and travel, increasing the speed and facility of infectious disease and resistant microorganism spread;
  7. The routine use of antimicrobials as growth promoters or preventive agents in food-producing animals

Self-Medication

An increasingly worrying cause of antimicrobial resistance is the self-medication of the developed world population.  When given the choice between first- and second-line drugs, some patients choose the more expensive second-line drugs, thinking that they will be better at fighting disease.  However, what they are really doing is allowing the microbes the chance to become resistant to the second-line drugs, thereby rendering first-line drugs useless for everyone else.  Therefore, diseases that used to be cured by a cheap, efficient drug are now resistant to it and to the next level of defense.

When people choose to self-medicate themselves, microbes get a chance to see and adapt to the antimicrobial weapons in our arsenal.  For example, self-medicated antimicrobials are often unnecessary, inadequately dosed, or may not have an adequate amount of drug.  Often times, people stop taking antimicrobials once they feel better, which can occur before the microbe has been completely eliminated, thereby increasing antimicrobial resistance.

Anti-bacterial Soap

Of all the ways a person can combat antimicrobial resistance, not using anti-bacterial soap is one of the easiest to do.  When we use soap that contains anti-bacterial properties, we are showing the bacteria weapons in our arsenal and giving them a chance to mutate and adapt.  With every time use of anti-bacterial soap, more and more bacteria are exposed to our arsenal, and more and more are given the chance to adapt and pass their method of survival on to other bacteria.

The fact is that regular, non-antibacterial soap, kills bacteria on its own.  Soap is a cleaning agent, like bleach, that kills bacteria on the spot.  Bacteria cannot adapt to bleach, or to soap, because it will always kill.  The CDC says, “Antibacterial-containing products have not been proven to prevent the spread of infection better than products that do not contain antibacterial chemicals.”

Unlike soap, antibiotics work by disrupting some process of the bacteria’s cell life, such as protein synthesis, which will lead to their death.  While this is great for illnesses caused by bacteria, it can only be done a certain number of times before the bacteria mutate, or figure out a way to resist the antibiotics that are interfering with their protein synthesis.  So every time you use anti-bacterial soap, you are giving more bacteria the chance to mutate and survive.  Traditional soap works just as well (perhaps even better) than anti-bacterial soap.

The APUA has this to say about antibacterial soap:  “To ensure that [antibiotics] continue to be effective when they are needed, products containing these antibacterials should only be used when they are essential to fight against infection… Generally, the best way to remove ‘bad’ bacteria is through good hand-washing practice using a non-bactericidal soap and water.  Proper hand-washing will remove 99.9% of bacteria, and normally, few other control measures are needed.”

Physicians Practices

Oftentimes, when a person feels sick from a common cold, they will go to the doctor and demand an antibiotic.  Physicians who are either too busy or too lazy will provide a prescription to placate the patient, without explaining that antibiotics to not treat colds.  Viruses cause colds; antibiotics kill bacteria.  Antibiotics do not treat viral infections; it is like trying to cure dementia with a band-aid.  According to the WHO, “Physicians can be pressured by patient expectations to prescribe antimicrobials even in the absence of appropriate indications.”

Patient Compliance

Another cause of microbial resistance is patience non-compliance with prescribed antimicrobials.  “Patients forget to take medication, interrupt their treatment when they begin to feel better, or may be unable to afford a full course, thereby creating an ideal environment for microbes to adapt rather than be killed” (WHO).

Consequences

When microbes become resistant to treatment, infections become more difficult to fight.  When a person has an illness caused by a microbe that is resistant to a drug, not only does his length of illness increase but also he will infect others with the antimicrobial resistant microbe.  In turn, the microbe will become more numerous and even more difficult to treat.

When the drugs that used to be used as a first-line of defense fail, the second- and third-line drugs must be used.  These drugs are more expensive and more toxic.  The WHO says, “In many countries, the high cost of such replacement drugs is prohibitive, with the result that some diseases can no longer be treated in areas where resistance to first-line drugs is widespread.”

“Even if the pharmaceutical industry were to step up efforts to develop new replacement drugs immediately, current trends suggest that some diseases will have no effective therapies within the next ten years” (WHO).

Need for Change

In 2001, the WHO launched the Global Strategy for Containment of Antimicrobial Resistance to recognize the problem of antimicrobial resistance.  The strategy recommends interventions to slow the resistance, including legislation regarding the sale of antimicrobial products.

The Centers for Disease Control and Prevention (CDC) provides a Get Smart antibiotics awareness program, “What everyone should know and do: Snort. Sniffle. Sneeze.  No Antibiotics Please!”  The website provides information on colds and flus, as well as general information on antibiotic resistance.

The CDC explains, “Almost every type of bacteria has become stronger and less responsive to antibiotic treatment when it is really needed.  These antibiotic-resistant bacteria can quickly spread to family members, schoolmates, and co-workers- threatening the community with a new strain of infectious disease that is more difficult to cure and more expensive to treat.  For this reason, antibiotic resistance is among CDC’s top concerns.”

The Alliance for the Prudent Use of Antibiotics (APUA) promotes proper antibiotic use and preventing antibiotic resistance on a global scale.  The APUA works with the WHO, Pan American Health Organization, and the CDC, among other organizations.  They also publish a quarterly newspaper about antibiotic use and resistance, and have done so since 1982.  The APUA received an unrestricted educational grant from bioMerieux and the CDC to study the economics of antibiotic overuse and antibiotic-resistant infections.

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Minimally Invasive Surgery

Within the last few years, a paradigm shift has occurred in the operating room:  surgeons no longer need to directly touch or even see what they are operating.  Endoscopic video imaging and advanced in instrumentation have converted open surgeries to endoscopic ones.  This has resulted in higher survival rates, fewer complications, and a quicker return to daily activities.

“Future research will focus on delivery of diagnostic and therapeutic modalities through natural orifices in which investigation is under remote control and navigation, so that truly ‘noninvasive’ surgery will be a reality” (JAMA).

Advantages

In addition to a speedier recovery and increased survival rate, “the pain, discomfort, and disability, or other morbidity as a result of surgery is more frequently due to trauma involved in gaining access to the area to perform the intended procedure rather than from the procedure itself” (JAMA).

Development

Minimally invasive surgery began in the fields of gynecology and orthopedic surgery, and is now found in “general surgery, urology, thoracic surgery, plastic surgery, and cardiac surgery” (JAMA).

Robotic Surgery

Some simple surgical procedures have been performed by a “robot”, or rather, a surgeon acting remotely.  However “there is no clear path to practical application at present because of expense, transmission delay, and medical and legal issues” (JAMA).  Rather than remote manipulation, robots used today gather information, assist with navigation, and enhance the surgeon’s dexterity.  For example, during a retinal vein thrombosis surgery, the surgeon inserts a thin tube (100-micron), using the help of robotics.  This technique is not possible without such dexterity enhancement.

Minimally invasive radical prostatectomy (MIRP)

Prostate removal can be performed via an opening in the abdomen (RRP) or by a minimally invasive and more costly MIRP.  From 2000 to 2006, there was an increase of robotic-assisted MIRP from 1% to 40% on radical prostatectomies.  A 2009 study, published in the Journal of the American Medical Association, compared the effectiveness of these two surgeries.  It found that people who had the minimally-invasive surgery had a shorter hospital stay, fewer complications and strictures, but experienced more urinary and genital complications, including incontinence and erectile dysfunction.

The study concluded that RRP, “with a 20-year lead time for dissemination of surgical technique relative to MIRP, remains the gold standard surgical therapy for localized prostate cancer.”  However the distinction should be made that RRP is the gold standard, not invasive surgery as opposed to minimally invasive surgery.  The study praises the use of minimally invasive surgery for many diseases, but says that RRP is better in this case because it is performed through a small hole, rarely causes significant pain, and results in only a 1-3 day stay in the hospital.

Minimally Invasive Check for Lung Cancer

Lung cancer is the most common cause of death by cancer in the United States.  For many patients with suspected lung cancer, surgery is the only method to confirm the diagnosis.

A study published in The Journal of the American Medical Association in 2008 compared the accuracy of three minimally invasive techniques to confirm lung cancer diagnosis.  The results of the study can be found here.  The significance of the study for our purposes is to showcase the capabilities of minimally invasive surgery, especially when the correct diagnosis of cancer rests in the balance.  “Accurate staging [diagnosis] of lung cancer is critical for choosing optimal therapy” (JAMA).  Therapies include surgical removal of cancerous lymph nodes and/or chemoradiation, depending on the type of lung cancer diagnosed.

The Mayo Clinic

The Mayo Clinic, the largest not-for-profit group practice in the world, is well respected in the medical community.  Many physicians there use minimally invasive surgery, also known as laparoscopic surgery, as “the preferred surgical approach for many illnesses.”  They have one of the largest minimally invasive surgical practices in the nation.

The Mayo Clinic is using robotic surgery, which it calls “an advanced form of minimally invasive surgery,” increasingly to aid the surgeon’s views and precision.  They have pioneered many advances in both minimally invasive and robotic surgery.

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Overview on Gene Therapy

Human DNA codes for the expression of everything from hair color to metabolism to genetic disorders.  DNA with mutations causes some of these disorders.  Gene therapy replaces or repairs these mutations, by providing “correct” DNA that is attached to a vector.  A vector is a vehicle for the DNA that is put together by researchers.  Most vectors are harmless viruses, although researchers are also developing non-viral vectors.

According to the American Medical Association (AMA), “Gene therapy is a novel approach to treat, cure, or ultimately prevent disease by changing the expression of a person’s genes.  Gene therapy is in its infancy, and current therapies are primarily experimental, with most human clinical trials still in the research stages.”

Gene therapy is hopeful for the treatment of 4,000 diseases caused by genetic disorders.  These include cancer, AIDS, cystic fibrosis, Parkinson’s and Alzheimer’s disease, Lou Gehrig’s disease, cardiovascular disease, and arthritis.

Positives of Gene Therapy

There are many possible functions of gene therapy (AMA).  The first, mentioned above, involves replacing defective or missing genes with normal ones.  Another possibility is the delivery of genes that can cause the death of cancer cells, or can cause cancerous cells to become normal again.  A third function is the delivery of genes from bacteria or viruses to prevent infections from them, as a vaccination.  Another function is the delivery of genes to promote new tissue growth or regeneration of damaged tissue.

Research

In 1990, the National Institute of Health performed the first successful gene therapy on a human.  It was for a four-year old child with adenosine deaminase (ADA) deficiency, which is caused by a single gene defect.  Since that time, human clinical trials have included such diseases as cystic fibrosis, severe immunodeficiency disease (SCID), Canavan’s disease, and Gaucher’s disease.  SCID is the only disease that has been cured by gene therapy.

The Journal of Gene Medicine provided the following data on diseases being addressed in gene therapy clinical trials in 2009:  Cancer diseases composed 64.5% of worldwide clinical trials, Cardiovascular diseases were 8.7%, monogenic diseases were 7.9%, infectious diseases were 8%, and neurologic diseases were 1.9%.  The complete table can be found here.

Shortcomings and Further Research

An article published in The Journal of the American Medical Association (AMA) discusses gene therapy in clinical settings.  Gene therapy clinical trials are classified by the stages.  For a gene therapy product to be available on the market, the clinical trial must be at Phase 2 or 3.  However these phases are “extremely expensive and would require financial support by pharmaceutical or biotechnology companies” (AMA).  Most inherited diseases are rare, so “there is little potential for return on investments in expensive research and clinical trials.”

Another problem with gene therapy is that it has only been successful at diseases caused by a single gene mutation.  For common diseases like heart disease and cancer that involve a large number of genes, a new approach for gene therapy must be found (AMA).  Obstacles include introducing the new gene to a large enough number of cells, preventing the cells from destroying it as foreign, and preventing infectious contaminates from entering at the commercial manufacturer site.

Stem Cells and Gene Therapy

Another possibility, published in The Journal of the American Medical Association, causes for the combination of neural stem cells and gene therapy (JAMA).  Spinal cord injuries can be especially overwhelming, yet research has found that some areas of the central nervous system (CNS) continue to produce neurons.  These stem cells, which are undifferentiated, have the capacity to become any cell in the body, including neurons.  These cells can be isolated and kept in a culture.  Then, “when transplanted back into the CNS, these stem cells have the capacity to migrate, to integrate with the host tissue, and to respond to local cues for differentiation.”

One practical application of this theory is the treatment of Parkinson’s disease.  Parkinson’s is a result of a decrease in dopamine caused by the destruction of dopamine-producing cells.  Stem cells can be grafted to become dopamine-producing cells, and then used to replace the degenerated cells.

“Grafted neural stem cells could potentially replace cells lost to injury, reconstitute the neuronal circuitry, and provide a relay station between the injured pathways above and below the lesion” (AMA).  This is a promising theory for the treatment of neurologic diseases, but more research and clinical trials must be done before a “cure” is found.

Ethical Concerns

Genetic therapy has only targeted the cells that are not passed to further generations.  This is called somatic gene therapy.  In germline gene therapy, sperm and egg cells are changed to pass genes onto the next generation.  This type of therapy is not being investigated.  In 2000, the American Association for the Advancement of Science (AAAS) provided a report that called for a moratorium on curing diseases using germline gene therapy.

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