Acne Vaccine
There will be nothing to push
Oleg Lischuk, Copper news based on New Scientist – In development: a vaccine for acne
The world's largest vaccine manufacturer Sanofi Pasteur (a division of the pharmaceutical giant Sanofi Aventis) has signed a two-year contract with the University of California at San Diego (UCSD) to develop an immunological method for the prevention and treatment of acne, also known as acne or acne rash.
The French company's interest in the problem of acne is quite understandable – it is one of the most common skin diseases. According to statistics, acne affects from 80 to 90 percent of adolescents, eight percent of people aged 25 to 34 years and five percent – aged 35 to 44 years. In 14 percent of children and adolescents aged 5 to 17, this disease occurs in moderate to severe form, often leading, as noted in a Sanofi press release, to "physical, psychological and social problems."
Currently, the market volume of acne medicines is estimated at more than three billion dollars a year.
Pimples appear when, due to changes in the amount and chemical composition of sebum (this occurs under the influence of hormones and other factors), the ducts of the sebaceous glands become clogged. As a result of such a blockage in the duct, the oxygen level is significantly reduced.
With a lack of oxygen, the bacterium Propionibacterium acnes – a component of the normal microflora of the skin – becomes more aggressive. In this state, it destroys the duct cells, trying to enter the bloodstream. The immune system reacts to the invasion by local inflammation with the formation of pus – this is how a pustule, or pimple, is formed.
Due to this mechanism of acne development, the modern approach to its treatment involves the appointment of antibacterial drugs. In mild cases, topical application of benzoyl peroxide, chlorhexidine and some other antiseptics is sufficient. If these drugs are ineffective, antibiotics that are active against P.acnes and penetrate well into the skin are used.
However, such treatment is not without drawbacks. All antibacterial drugs act non-specifically, killing a number of beneficial microorganisms and disrupting the normal composition of the skin microflora. In addition, with a chronic course of acne that requires long-term administration of antibiotics, P.acnes may develop resistance to these drugs.
This forces researchers to look for alternative approaches to acne treatment. However, until recently there were few developments in this area – the task was complicated by the fact that laboratory animals do not suffer from acne.
The laboratory of Chunming Huang (Chun-Ming Huang) at UCSD managed to create an animal model of the disease. To do this, scientists injected P.acnes into the skin of a mouse ear, which led to the development of inflammation.
In 2008, employees of the same laboratory prophylactically injected experimental animals with two types of the simplest experimental vaccines, one of which contained whole killed bacteria, and the other – the protein of their shell. Both of these drugs resulted in a significant decrease in the intensity of inflammation compared to the unvaccinated control group.
Thus, it has been shown that immunological methods are effective for combating acne. However, the used vaccines also attack non-aggressive P.acnes, which disrupts the normal microflora and makes the skin vulnerable to pathogenic bacteria.
Therefore, the researchers decided to find a different approach. They found in the DNA of propionibacteria a gene encoding the CAMP protein (the Christie–Atkins–Munch-Petersen factor), which various bacteria use to attack human cells.
By the method of genetic engineering, the CAMP gene was introduced into the DNA of a daikon (Japanese radish), which thanks to this began to synthesize the desired protein. Then an aerosol from the ground leaves of the plant was injected into the nose of laboratory mice to cause them to produce antibodies to CAMP.
These antibodies were added to a culture of P.acnes growing on a nutrient medium, where they bound to the CAMP developed by the bacterium. When this bacterial culture was injected into the skin of mice, the inflammation was much less than when using untreated P.acnes.
At the same time, treatment aimed at CAMP should not cause the selection of resistant bacteria, since it does not kill them, scientists emphasize. Antibodies to CAMP also do not affect the composition of the skin microflora, since P.acnes produce this protein only when there is a lack of oxygen in the blocked ducts of the sebaceous glands.
These developments of Juan's laboratory were the reason for the conclusion of a contract with Sanofi Pasteur. According to the company's press release, cooperation with the laboratory is aimed at developing "an immunological approach to the prevention and treatment of acne aimed at the specific neutralization of propionibacteria factors in inflammation." The amount of the concluded contract is not disclosed.
As part of the contract, the laboratory plans to test various CAMP neutralization methods suitable for use in medical practice. One of these methods, the scientists reported, will be the production of ready-made monoclonal antibodies to the protein, which can be injected into the skin using microneedles.
Hopefully, the final drug will not be based on this technique. Firstly, obtaining monoclonal antibodies is not a cheap process, which will clearly affect the price of treatment, and therefore its availability. And secondly, from 80 to 90 percent of teenagers are unlikely to be delighted with the upcoming course of intradermal injections, especially on the face.
But in itself, the near prospect of creating a reliable and harmless treatment for acne cannot but rejoice – after all, the same teenagers will get a real chance to get rid of the "physical, psychological and social problems" mentioned by Sanofi.
Portal "Eternal youth" http://vechnayamolodost.ru
28.09.2011