A new, non-injectable hepatitis B immunization strategy has been developed by researchers at the Center for Neuroscience and Cell Biology (CNC) of the Faculty of Pharmacy, University of Coimbra, in collaboration with the University of Geneva. The formula is a vaccine in nasal spray form.
Hepatitis B is an infectious disease transmitted by exposure to the blood or body fluids of a person carrying the HBV virus. After infection, the virus affects liver cells and can lead to the death of the patient. The World Health Organization estimates that annually, diseases associated with hepatitis B are responsible for the deaths of 780,000 people worldwide.
In developing countries where financial and human resources to support the costs of injectable vaccine administration are scarce, nasal immunization is a cheaper and safer alternative. This therapy also eliminates the risk of infection caused by the reuse of syringes when administering injections.
Olga Borges, researcher at CNC's Vector and Gene Therapy Group, and one of the coordinators of this project, explains that the genetic vaccine designed as a nasal spray has a composition based on "plasmids". These are molecules theoretically more resistant to temperature variations in the body, which transmit genetic information (DNA) into the cells, activating the defense mechanisms against hepatitis B virus. In the process, the therapeutic molecules are transported in polymeric nanoparticles from the nasal mucosa to the interior of the cells.
In the CNC statement, the researcher highlights the possibilities opened by the developed research. "The nanoparticles developed may also be used in the composition of vaccines that prevent sexually transmitted diseases (STDs), because they induce the production of antibodies by our body at the level of the vaginal mucosa more effectively than injectable vaccines," he says.
The process of inducing antibodies by the nasal route was tested in mice, which returned immune response from this formulation. It was shown that the nasal route allows "a greater capacity to induce antibodies in the mucous membrane of the reproductive organs" than the oral route.
This line of research was initiated in 2003, with the development of nanoparticles for the production of non-injectable vaccines. In 2012 it was funded by FCT under the R&D projects of the Bioengineering, Biotechnology and Biochemistry area.
The work is published in the renowned scientific journal "Molecular Pharmaceutics".
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