Mª Isabel Murillo defended her doctoral thesis entitleddevelopment of a subcellular vaccine against brucellosis using biodegradable microparticles as adjuvant", carried out at the Departments Microbiology and Pharmacy and Pharmaceutical Technology of the University of Navarra, under the supervision of Dr. Carlos Gamazo and Dr. Mª del Mar Goñi. Dr. Murillo considers that the vaccines currently used are effective only to a certain extent, because they have some drawbacks: "They interfere in the diagnosis of the disease and show some residual virulence, so they can produce abortions in animals and even be pathogenic for humans."

The novelty of the vaccine developed by the team on which the researcher has worked lies both in its composition, which contains extracts of the bacterial cell envelope, and in the adjuvant employee. The expert assures that the employment cell fractions constitutes an obstacle to its efficacy that can only be overcome through the use of adjuvants or "substances that increase the immune response to any component with which it is mixed". The process that makes the vaccine operative consists of the microencapsulation of the cell extracts in polyester microparticles of between one and three thousandths of a millimeter. According to Mª Isabel Murillo, "the polyesters degrade slowly in the organism and give rise to non-toxic products that will be metabolized".

The researcher from the University of Navarra explained that the efficacy of the vaccine in mice was notorious and even improved the results obtained with the commercial vaccine. In her opinion, the latter "has the disadvantage of using live bacteria that threaten to infect the vaccinated animals and the veterinarians or farmers who handle it". In addition, he announced that his thesis " thesis resulted in a patent and several publications" and noted that his findings have led to negotiations with the pharmaceutical industry with a view to purchasing the patent.

The research group , led by Dr. Carlos Gamazo and Dr. Juan Manuel Irache, has as its next goal to demonstrate its efficacy in sheep, for which it has received the support of two ministries, the Ministry of Education and the Ministry of Science and Technology. "Soon, the programs of study in the field will begin," she said, reference letter to a project in partnership with the Agricultural Research Service of the Diputación General de Aragón. On the other hand, the new doctor announced the preparation of a combined vaccine for brucellosis and salmonellosis in sheep, based on the same strategy of including subcellular fractions in adjuvants.