The porines of Gram-negative bacteria are very attractive candidates for the elaboration of vaccines against pathogens of these characteristics. These are proteins from the external membrane of bacteria and they have a clearly defined biological function in the transport of nutrients. The PorA porine of Neisseria meningitides offers big possibilities for the elaboration of a recombinant vaccine against the meningococcal meningitis. The codifying gene for PorA was isolated from nine different N. meningitides stumps, being included the most frequent clinical isolation in Cuba.

It was carried out a sequence analysis that allowed defining the variable regions, against which there are directed bactericidal and protective antibodies induced against the protein. PorA was expressed at high levels in Escherichia coli, using different expression systems, and the purified antigen was immunologically characterized. Recombinant PorA was reconstituted with detergents and it was included in liposomes, being obtained high antibodies levels with bactericidal activity against N. meningitides. There were also designed and expressed in E. coli, chimerical proteins that contained PorA fragments belonging to several subtypes, which were immunocharacterized. There were obtained synthetic peptic from the hypervariable regions of this protein and its immunogenity was studied, being obtained high levels of antibodies in several lines of the mouse. Clinical peptides were also synthesized, which were conjugated to carrier proteins, and immunologic studies in mice revealed that the peptides were immunogenic and the generated antibodies reacted with the negative protein. The variable PorA regions were expressed in the surface of filamentous phage M13, and there were obtained antibodies directed against the variable region 2 that recognized the protein in the Bacteria surface and showed bactericidal activity against N. meningitides.

The presented result has given rise to 7 publications, 3 of them in prestigious magazines. It is meritorious its contribution to knowledge, and it creates the technological bases for the development of new possible vaccinal formulations for the control of this disease.