Nicotine Vaccine Offers Cure for Nicotine Addiction to Help Quit Smoking
A radically new approach for vaccination offers a better way to treat chronic nicotine addiction and so help people quit smoking. Many 'quit smoking' vaccines have been researched in the past and tested in animals.
These vaccines stimulate the immune system to generate antibodies that lock onto to nicotine and render it ineffective as a stimulant. This is the same basic method that is used to vaccinate people to protect them against disease organisms.
However the quantities of nicotine in the bloodstream far exceed those of a disease organism trying to invade the body. Previous vaccines have failed in trails because the quantity of nicotine in the blood swamps the level of antibodies that can bind to it, rendering it useless in stimulating the brain.
The new approach uses a disease organism, a virus to deliver the punch. Scientists have genetically modified a harmless virus by encoding the instructions for manufacturing nicotine antibodies within the virus.
The injected virus harmlessly infects the liver cells of the mice without becoming incorporated into the human genes in the cell. In effect this turns part of the liver into a factory stimulating the production of antibodies for nicotine.
In mice, a single treatment lowered nicotine levels by 85% lower and blocked the physiologic effects of nicotine.It is not known if this treatment will work as effectively in humans but this reduction should be enough to help people quit smoking.
This treatment could be very effective because people who start smoking again, or start for the first time, will receive no pleasure from smoking due to the stimulant effect of nicotine on the brain.
Years of research are still required before the method could be tested on people.However, the virus vectors have been used in over 80 clinical trials worldwide for a variety of diseases.This includes Hemophilia, congestive heart failure and Parkinson's disease.
In mice treated with this vector, blood concentrations of the anti-nicotine antibody depended on the dose. The antibody was shown to be highly specific for nicotine. The antibody was shown to be effective in shielding the brain from injected nicotine, lowering nicotine concentrations to only 15% of mice who were not treated.
The vaccine was shown to be effective in blocking nicotine-mediated changes in blood pressure, heart rate, and muscle activity of the mice. So the vaccine was shown to block the impact of nicotine on the brain.
The virus vector is an adeno-associated virus (AAV) which infects humans and other primates and other species, without causing any diseases and only stimulates only a very minor immune response to the vector itself.
The advantage of this method is that the virus can infect both dividing and non-dividing cells. It also does not get incorporated into the chromosomes and the genome of the host cell, unlike many other viruses.
The virus simply remains in the cell and reproduces itself. It can be engineered to stimulate an immune response to nicotine.
The researchers are very hopeful that this 'smoking vaccine' method may finally help the millions of smokers throughout the world who have tried to stop, but have exhausted all existing methods without success.
A more controversial aspect is that children could be vaccinated for nicotine suppression before they even started smoking.
The main issues for testing in humans is whether the immune response is just as effective in mice, testing for any harmful effects of the virus vector and how effective it is in helping people quit smoking.
Smoking addictions can have both physical and psychological aspects and the question is whether removing the nicotine hit from smoking will actually help people quit.
© 2012 Dr. John Anderson