RESUMEN
The physico-chemical characteristics and immunogenicity of a candidate vaccine against otitis media, prepared from recombinant lipidated outer membrane proteins (rLP4 and rLP6) from non-typeable Haemophilus influenzae (NTHi) and of the ubiquitous cell surface protein UspA2 from Moraxella catarrhalis, were evaluated. Optical spectroscopy, size exclusion chromatography and gel electrophoresis were used to characterise the purified protein components and assess their purity and molecular sizes. The results showed that the three proteins were highly purified. Possible dimers in rLP4, dimers and multimers in rLP6 and UspA2 were detected. Small amounts of rLP4 and rLP6 dimers and most of UspA2 complexes remained tightly bound even after SDS treatment under reducing conditions. Immunogenicity studies showed that all proteins induced substantial antibody responses in mice immunised with AlPO4-adsorbed rLP4, rLP6 or UspA2 or a combination of these proteins. However, combination of these proteins resulted in a reduced response to rLP4 and rLP6, but not to UspA2, suggesting interference between these proteins which should be taken into consideration during the development and evaluation of this vaccine.
Asunto(s)
Vacunas Bacterianas/química , Vacunas Bacterianas/inmunología , Vacunas contra Haemophilus/química , Vacunas contra Haemophilus/inmunología , Moraxella catarrhalis/inmunología , Adyuvantes Inmunológicos/farmacología , Compuestos de Aluminio/farmacología , Animales , Western Blotting , Proliferación Celular , Fenómenos Químicos , Química Física , Cromatografía en Gel , Dicroismo Circular , Citocinas/biosíntesis , Electroforesis en Gel de Poliacrilamida , Inmunidad Celular/efectos de los fármacos , Inmunoglobulina G/análisis , Inmunoglobulina G/inmunología , Proteínas de la Membrana/inmunología , Ratones , Ratones Endogámicos BALB C , Microscopía Fluorescente , Peso Molecular , Fosfatos/farmacología , Bazo/citología , Bazo/inmunología , Bazo/metabolismo , Vacunas Combinadas/química , Vacunas Combinadas/inmunología , Vacunas Sintéticas/química , Vacunas Sintéticas/inmunologíaRESUMEN
An urgent need exists for vaccines to prevent infections caused by nontypeable Haemophilus influenzae and Moraxella catarrhalis. These bacteria cause otitis media in children, a clinical problem associated with enormous morbidity and cost. H. influenzae and M. catarrhalis also cause lower respiratory tract infections in adults with chronic lung disease. Infections in this clinical setting are associated with disability and death. Recent progress in identifying potential vaccine antigens in both bacteria raises great promise in developing effective vaccines. This paper reviews the key issues in vaccine development for H. influenzae and M. catarrhalis, including areas where progress has been stalled, and proposes areas that deserve investigation in the next 5 years.