St. to generate detectable cellular immune responses. In contrast, LTK63, LTR72, and LTwt significantly augmented NadA-specific gamma interferon, interleukin-4 (IL-4), IL-5, and IL-10 production by spleen and lymph node cells, suggesting that both Th1 and Th2 cells were induced in vivo. The strongest cellular reactions and highest bactericidal antibody titers were generated with LTR72 as the adjuvant. These findings demonstrate that the quality and magnitude of the immune responses generated by mucosal vaccines are affected from the antigen as well as the adjuvant and suggest that nose delivery of NadA with mucosal adjuvants offers substantial potential in the development of a mucosal vaccine against serogroup B meningococci. is definitely a major causative agent of bacterial meningitis and fatal septicemia. Babies, young children, and adolescents are most susceptible to illness. Mortality rates among infected individuals are high (around 10%), and death can result in hours, despite treatment with appropriate antibiotics. Furthermore, up to 25% of survivors suffer from neurological sequelae. Five major pathogenic serogroups of have been identified based on the chemical composition of the bacterial capsule (A, B, C, Y, and W135). Capsular polysaccharide vaccines are available against four serogroups (A, C, Y, and W135). Although these are effective in adults, safety is short-lived and they have very little efficacy in children under 18 months of age (32). In late 1999, a second-generation glycoconjugate vaccine was launched against serogroup C. This vaccine is definitely highly efficacious in all age groups including babies, and since its intro there has been a 90% decrease in instances of serogroup C disease (27). Related vaccines against the A, Y, and W135 serogroups are under development (20). There is currently no licensed commercial vaccine against serogroup B meningococci available in Europe or the United States. Strains from this serogroup are responsible for most instances of illness in Europe, around a third of instances in the United States, and about half of the meningococcal infections found elsewhere in the world (with the exception of sub-Saharan Africa, where serogroup A strains cause more than 90% of meningococcal infections) (5, 13, 28). Vaccines against serogroup B strains have proved difficult to develop. The polysaccharide antigen is definitely poorly immunogenic in humans since it mimics a widely distributed human being carbohydrate [(28)varieties are subject to antigenic variation, they offer no safety against illness with AA147 heterologous strains (26). AA147 The challenge therefore is to identify novel antigens which are highly conserved across a range of virulent group B strains and are capable of inducing bactericidal antibodies, a correlate of safety against (2). The complete genome sequence of a serogroup B strain of has recently been identified (35). During the course of this work, unassembled fragments of the genome were analyzed to identify novel proteins which were potentially surface revealed or secreted. These proteins were then indicated in MC58 genome sequence]) is definitely a serine protease autotransporter protein which has structural homology with immunoglobulin A (IgA) serine proteases and 76% sequence homology with Hap, an adhesin from (11). The protein has been shown, by immunogold electron microscopy, to be localized in the meningococcal surface. It is also cleaved and secreted by (10). It is highly conserved among disease-associated strains, and there is evidence that it is an adhesin which may be involved in the initial connection between meningococci and epithelial cells (31). It is identified by serum from convalescents and service providers of meningococci, suggesting that it is indicated in vivo and is immunogenic in humans (10). NhhA (NMB0992), a putative adhesin, is also highly conserved among virulent meningococci and identified by convalescent-phase sera (18, 30, 37). The protein is definitely a homolog C13orf18 of Hia, a fibrillar adhesin from (33). It is located in the bacterial outer membrane and may form oligomers. NadA (NMB1994) is definitely surface exposed in which is AA147 involved in serum resistance (7). It has been found in approximately 50% of 150 meningococcal strains representing major disease-associated serogroups. However, among a subset of hypervirulent lineages.