Wednesday, April 9, 2008

The Future Vaccination ---- Tattoos

Tattoo is always seen as a mere fashion icon. However, one would never expect the painful process of tattooing has a great potential value in the medical field – DNA vaccination by tattooing.

First, what is DNA vaccination? It is a process whereby a DNA vaccine is administered into the body, and the body will convert the information in the DNA vaccine into a protein which activates an immune response. This was initially done via simple injection of DNA but it is considered to be one of the less effective methods of DNA vaccination as it often failed to produce the expected immune response. A study done by Dana Pokorna, Ivonne Rubio and Martin Müller shows that tattooing is a more effective way of delivering DNA vaccines than intramuscular injection.

A coat protein from the human papillomavirus (HPV, the cause of cervical cancer) was used as a model DNA vaccine antigen in their research. 3 ways of DNA vaccination were examined and compared, which are tattooing, standard intramuscular injection with adjuvants, and injection without molecular adjuvants (adjuvants function to boost immune response).

Tattooing gave a stronger humoral (antibody) response and cellular response than intramuscular injection, even with adjuvants in the latter. The study shows that 3 doses of DNA vaccine administered by tattooing produced at least 16 times higher antibody levels than 3 intramuscular injections with adjuvant included.

Tattooing is done with a solid vibrating needle, causing a wound and inflammation to stimulate immune system. In the study, the skin surface area of the mouse of approximately 2cm2 was tattooed by 30 times repeated two-second-lasting treatments with the tattoo needle vibrating at 145 punctures per second. Results show that DNA-tattooing induces higher levels of specific antibodies cellular immune responses compared to intramuscular injection.

Tattooing involves much larger area of the skin than intramuscular injection, thus DNA vaccine can enter more cells, accounting for a stronger immune response. Tattooing hurts tremendously but Müller explained that: "This is probably what makes it work better than normal injections because the tissue is damaged and this affects the immune cells, which then look out for antigens."

The advantages of tattoo vaccination are the low price of the tattoo device and a standardized method for the application. On the other hand, not only that tattooing includes pain on animals, but it is also a cumbersome procedure. Nevertheless, it seems to be the method of choice if faster and stronger immune responses need to be achieved, such as in the case to treat cancer. Potential applications might be vaccination of life stock for prophylaxis or for human therapeutic purposes.

Reference list

Pokorna, D, Rubio, I, Müller, M, 2008, ‘DNA-vaccination via tattooing induces stronger humoral and cellular immune responses than intramuscular delivery supported by molecular adjuvants’, Genetic Vaccines and Therapy, vol.6, no.2.

Tattoos: Vaccinations of the Future?, viewed 7 February 2008.

McGrath, M, 2008, ‘Tattoos may help deliver vaccine’, BBC News, 7 February 2008.

Posted by Yoon E Kok

Student Number: 41498936

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