Administer vaccines via the skin

Administer vaccines via skin

09/28/2014

Tetanus, Hepatitis, TBE: Vaccines are available for many infectious diseases. Many people shy away from the injection. German scientists have now shown that it is also possible to administer vaccines via the skin. Especially in developing countries, the situation could be improved by new vaccination methods.

Administer vaccines via the skin
Tetanus, hepatitis A and B, tick-borne encephalitis (TBE): Vaccines are available against these and many other infectious diseases. In most cases they are given by injection. But for various reasons, alternative methods have been researched for years. Scientists at the Helmholtz Institute for Pharmaceutical Research Saarland (HIPS) and the Helmholtz Center for Infection Research (HZI) in Braunschweig have now shown that it is indeed possible to administer vaccines via the skin with the aid of nanotechnological formulations. The previous vaccination methods could be significantly improved. The researchers published their findings in the journal „Nanomedicine“.

Disadvantages of vaccination by syringe
Traditional syringe vaccination has several disadvantages. However, it is not only about the fear of the needle, which makes some people shy away from vaccination, but above all about the logistics associated with the production and application. „It is very costly and expensive to produce such vaccines and trained personnel are needed for the application“, explained Prof. Claus-Michael Lehr, head of the department „Drug Delivery“ at the HIPS in a message. „This is a problem, especially in developing countries.“ For this reason, he and his colleagues at HZI have been looking for new vaccination methods for some time.

Researchers use nanoparticles
Now they have found that it is indeed possible to bring vaccines into the body via the anchoring of the hair in the skin, the so-called hair follicles, in order to trigger an immune response. The researchers used nanoparticles as packaging for the vaccines, which are deposited in the skin's wrinkles and hair follicle openings and can pass through the skin without injuring them. Since the follicles are not completely surrounded by cornea, this is not in the way of the nanocarriers and the path is thus free.

Sufficient amount needed for an immune response
However, a sufficient amount of the vaccine must enter the body to actually cause an immune response. „This is not possible with the nanoparticles“, said Prof. Carlos Alberto Guzman, head of the department „Vaccinology and applied microbiology“ at the HZI with. „However, we solve this problem by administering not only the active substance but also the adjuvants developed at HZI using the nanocarriers. These additives boost the immune response in the body“. Thus, a corresponding reaction in the body is triggered, although the amount of antigens is actually not enough for it.

Vaccination reactions of the skin are not rare
„This shows that it is possible to develop vaccines that could be used without injection“, so teaching. „Ideally, a skin cream could be applied in the future and you would be vaccinated“. This might be beneficial, inter alia, for those patients who have skin problems as a result of vaccination, such as redness and swelling around the injection site. Vaccination reactions of the skin are not uncommon, sometimes even large parts of the body are affected. For example, in the combination vaccine against measles, mumps and rubella, on average, five percent of all cases involve the so-called vaccine creams, a measles-like skin rash.

Creams would be much cheaper to manufacture
If appropriate creams for vaccination come in future, they would be much cheaper to manufacture. Above all, no trained personnel would be needed to use them effectively. Thus, such vaccines would be a major step forward in halting epidemics in developing countries such as the current Ebola epidemic in West Africa. In addition, a use of this method in addition to the vaccines to protect against infectious diseases in desensitization therapies (hyposensitization) in allergies conceivable. (Ad)