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Meningococcal Disease Caused by Neisseria meningitidis Serogroup B Serotype 4 in São Paulo, Brazil, 1990 to 1996

Sacchi,Claudio Tavares; Lemos,Ana Paula Silva de; Camargo,Maria Claudia C.; Whitney,Anne M.; Melles,Carmo Elias A.; Solari,Claude André; Frasch,Carl E.; Mayer,Leonard W.
Fonte: Instituto de Medicina Tropical Publicador: Instituto de Medicina Tropical
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/1998 EN
Relevância na Pesquisa
66.5%
A large epidemic of serogroup B meningococcal disease (MD), has been occurring in greater São Paulo, Brazil, since 1988.21 A Cuban-produced vaccine, based on outer-membrane-protein (OMP) from serogroup B: serotype 4: serosubtype P1.15 (B:4:P1.15) Neisseria meningitidis, was given to about 2.4 million children aged from 3 months to 6 years during 1989 and 1990. The administration of vaccine had little or no measurable effects on this outbreak. In order to detect clonal changes that could explain the continued increase in the incidence of disease after the vaccination, we serotyped isolates recovered between 1990 and 1996 from 834 patients with systemic disease. Strains B:4:P1.15, which was detected in the area as early as 1977, has been the most prevalent phenotype since 1988. These strains are still prevalent in the area and were responsible for about 68% of 834 serogroup B cases in the last 7 years. We analyzed 438 (52%) of these strains by restriction fragment length polymorphism (RFLPs) of rRNA genes (ribotyping). The most frequent pattern obtained was referred to as Rb1 (68%). We concluded that the same clone of B:4:P1.15-Rb1 strains was the most prevalent strain and responsible for the continued increase of incidence of serogroup B MD cases in greater São Paulo during the last 7 years in spite of the vaccination trial.

Genetic relationships among serogroup B: serotype 4 Neisseria meningitidis strains

LEMOS,Ana Paula S.; SACCHI,Claudio T.; PAIVA,Maria V.; YARA,Teresa I.; MELLES,Carmo Elias A.; MAYER,Leonard W.
Fonte: Instituto de Medicina Tropical Publicador: Instituto de Medicina Tropical
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2001 EN
Relevância na Pesquisa
66.34%
We compared the results obtained by serotyping of PorB epitopes using an expanded panel of monoclonal antibodies (mAb) including mAb 7 and mAb 10, with results obtained by RFLP of rRNA genes (ribotyping). The purpose of this study was to assess the correlation between phenotypic- and genotypic- methods for typing N. meningitidis. The ribotypes obtained using ClaI or EcoRV endonucleases grouped the strains in seven and two different patterns, respectively. This additional characterization of PorB epitopes improved the correlation between these two methods of typing N. meningitidis.

Distribution of Neisseria meningitidis Serogroup B Serosubtypes and Serotypes Circulating in the United States

Tondella, Maria Lucia C.; Popovic, Tanja; Rosenstein, Nancy E.; Lake, D. B.; Carlone, George M.; Mayer, Leonard W.; Perkins, Bradley A.;
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /09/2000 EN
Relevância na Pesquisa
76.33%
Because the Neisseria meningitidis serogroup B (NMSB) capsule is poorly immunogenic in humans, immunization strategies have focused on noncapsular antigens. Both PorA and to a lesser extent PorB are noncapsular protein antigens capable of inducing protective bactericidal antibodies, and vaccines based on the outer membrane protein (OMP) components of serogroup B meningococci have been shown to be effective in clinical trials. Multiple PorA antigens seem to be needed to prevent endemic meningococcal disease around the world, and a hexavalent PorA-based meningococcal vaccine has recently been developed in The Netherlands. To evaluate the distribution of NMSB PorA and PorB antigens in the United States, serosubtyping and serotyping were done on 444 NMSB strains isolated in the active surveillance areas of the United States (total population, 32 million) during the period 1992 to 1998. A total of 244 strains were isolated from sporadic cases of meningococcal disease, and 200 strains were isolated from an epidemic in Oregon. A panel of 16 mouse monoclonal antibodies reactive with PorA and 15 monoclonal antibodies reactive with PorB were used. Among the NMSB isolates obtained from sporadic cases, the most prevalent serosubtypes were P1.7...

Serosubtypes and PorA Types of Neisseria meningitidis Serogroup B Isolated in Brazil during 1997-1998: Overview and Implications for Vaccine Development

Sacchi, Claudio T.; Lemos, Ana Paula S.; Popovic, Tanja; Cassio de Morais, Jose; Whitney, Anne M.; Melles, Carmo Elias A.; Brondi, Luciana M. G.; Monteiro, Lucia M. C.; Paiva, Maria V.; Solari, Claude A.; Mayer, Leonard W.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /08/2001 EN
Relevância na Pesquisa
66.31%
Meningococcal disease caused by N. meningitidis serogroup B (MenB) has been endemic in Brazil since 1997. In this study, we determined the prevalence of serosubtypes of MenB isolated in 10 Brazilian states and the Federal District during 1997 and 1998 and investigated the extent of PorA VR sequence variation among the most prevalent serosubtypes to evaluate the possible use of an outer membrane vesicle (OMV)-, PorA-based vaccine to prevent meningococcal disease in Brazil. During this period, a total of 8,932 cases of meningococcal disease were reported. Only 42% (n = 3,751) of the reported cases were laboratory confirmed, and about 60% (n = 2,255) of those were identified as MenB. Among 1,297 MenB strains selected for this study, the most prevalent serosubtypes were P1.19,15 (66%), P1.7,1 (11%), and P1.7,16 (4%). PorA VR typing showed that 91% of the P1.19,15 strains analyzed had VR1 and VR2 sequences identical to those of the prototype strain. No sequence variation was detected among the 40 strains representing all isolated MenB P1.7,16 strains in the three southern states, where this serosubtype accounts for 75% of the serosubtypes identified. Similarly, all P1.7,1 strains were identified by PorA typing as P1.7-1,1. Although further improvements in the reporting of cases and collection of strains in Brazil are needed...

Functional Activity of Anti-Neisserial Surface Protein A Monoclonal Antibodies against Strains of Neisseria meningitidis Serogroup B

Moe, G. R.; Zuno-Mitchell, P.; Lee, S. S.; Lucas, A. H.; Granoff, D. M.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /06/2001 EN
Relevância na Pesquisa
66.57%
Neisserial surface protein A (NspA) is currently being investigated with humans as a candidate vaccine for the prevention of meningococcal disease. Although NspA is highly conserved, the ability of anti-NspA antibodies to bind to or elicit complement-mediated bactericidal activity against diverse Neisseria meningitidis serogroup B strains is controversial. To evaluate strain differences in NspA surface accessibility and susceptibility to bactericidal activity, we prepared murine immunoglobulin G2a anti-NspA monoclonal antibodies (MAbs) and evaluated their functional activity against 10 genetically diverse N. meningitidis serogroup B strains. By colony Western blot, all 10 strains expressed NspA as detected by one or more MAbs. By flow cytometry, two MAbs were found to bind to the bacterial surface of 6 of the 10 strains. In addition, two strains showed variable NspA surface accessibility for the MAbs despite being uniformly positive for NspA expression by colony Western blotting. Only 4 of the 10 strains were susceptible to anti-NspA complement-mediated bacteriolysis. Passively administered MAb protected infant rats from developing bacteremia after challenge with N. meningitidis serogroup B strain 8047 (surface binding positive, susceptible to anti-NspA bacteriolysis)...

Standardization of Neisseria meningitidis Serogroup B Colorimetric Serum Bactericida Assay

Rodríguez, Tamara; Lastre, Miriam; Cedré, Barbara; Campo, Judith del; Bracho, Gustavo; Zayas, Caridad; Taboada, Carlos; Díaz, Miriam; Sierra, Gustavo; Pérez, Oliver
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /01/2002 EN
Relevância na Pesquisa
66.38%
The correlate of protection for serogroup B meningococci is not currently known, but for serogroup C it is believed to be the serum bactericidal assay (SBA). The current SBAs are labor intensive and the variations in protocols among different laboratories make interpretation of results difficult. A colorimetric SBA (cSBA), based on the ability of Neisseria meningitidis serogroup B to consume glucose, leading to acid production, was standardized by using group B strain Cu385-83 as the target. The cSBA results were compared to those obtained for a traditional colony-counting microassay (mSBA). Glucose and bromocresol purple pH indicator were added to the medium in order to estimate growth of cSBA target cell survivors through color change. Different variants of the assay parameters were optimized: growth of target cells (Mueller Hinton agar plates), target cell number (100 CFU/per well), and human complement source used at a final concentration of 25%. After the optimization, three other group B strains (H44/76, 490/91, and 511/91) were used as targets for the cSBA. The selection of the assay parameters and the standardization of cSBA were done with 13 sera from vaccinated volunteers. The titers were determined as the higher serum dilution that totally inhibited the bacterial growth marked by the color invariability of the pH indicator. This was detected visually as well as spectrophotometrically and was closely related to a significant difference in the growth of target cell survivors determined using Student’s t test. Intralaboratory reproducibility was ±1 dilution. The correlation between bactericidal median titers and specific immunoglobulin G serum concentration by enzyme immunoassay was high (r = 0.910...

Ribotyping as an additional molecular marker for studying Neisseria meningitidis serogroup B epidemic strains.

Tondella, M L; Sacchi, C T; Neves, B C
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /11/1994 EN
Relevância na Pesquisa
76.5%
The molecular method of ribotyping was used as an additional epidemiological marker to study the epidemic strains of Neisseria meningitidis serogroup B, referred to as the ET-5 complex, responsible for the epidemic which occurred in greater São Paulo, Brazil. Ribotyping analysis of these strains showed only a single rRNA gene restriction pattern (Rb1), obtained with ClaI restriction enzyme. This method, as well as multilocus enzyme electrophoresis, provided useful information about the clonal characteristics of the N. meningitidis serogroup B strains isolated during this epidemic. The N. meningitidis serogroup B isolates obtained from epidemics which occurred in Norway, Chile, and Cuba also demonstrated the same pattern (Rb1). Ribotyping was a procedure which could be applied to a large number of isolates and was felt to be appropriate for routine use in laboratories, especially because of the convenience of using nonradioactive probes.

Anti-Idiotypic Antibody as a Potential Candidate Vaccine for Neisseria meningitidis Serogroup B

Park, In Ho; Youn, Ju Ho; Choi, In-Hong; Nahm, Moon H.; Kim, Se Jong; Shin, Jeon-Soo
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /10/2005 EN
Relevância na Pesquisa
66.31%
Sepsis and meningitis caused by Neisseria meningitidis serogroup B (NMGB) are serious diseases in infants and young adults, but no effective vaccine is available. The capsular polysaccharide (PS) of NMGB has poor immunogenicity and a structural similarity to polysialic acid (PSA) on neuronal tissue that may elicit autoantibodies. Using HmenB3, a protective and nonautoreactive monoclonal antibody (MAb) to NMGB capsular PS, we produced an anti-idiotypic MAb, Naid60, which mimics the capsular PS of NMGB. We produced an anti-anti-idiotypic MAb, MoB34, by using the immunogenic site on Naid60 responsible for inducing the anti-NMGB PS antibody response. MoB34 elicited the complement-mediated killing of representative strains of serogroup B meningococci. MoB34 did not bind to CHP-134, a neuroblastoma cell line expressing α(2-8) PSA, or to mouse brain cryosections at a high concentration. Naid60-keyhole limpet hemocyanin immunization inhibited the growth of live NMGB in intraperitoneally challenged mice; in contrast, three of five control mice developed bacteremia. Thus, Naid60 has an immunogenic site that elicits antibodies with bactericidal activity against NMGB and no autoimmunity to PSA. We suggest that the immunogenic region of Naid60 is a candidate for the development of a new vaccine against NMGB.

Agonists of Toll-Like Receptors 3, 4, 7, and 9 Are Candidates for Use as Adjuvants in an Outer Membrane Vaccine against Neisseria meningitidis Serogroup B▿

Fransen, Floris; Boog, Claire J.; van Putten, Jos P.; van der Ley, Peter
Fonte: American Society for Microbiology (ASM) Publicador: American Society for Microbiology (ASM)
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
66.34%
The bacterium Neisseria meningitidis is the causative agent of meningitis and sepsis. A generally effective vaccine against N. meningitidis serogroup B is not yet available, but outer membrane vesicle vaccines are in development. These vaccines contain lipopolysaccharide (LPS). The inclusion of N. meningitidis wild-type LPS in a vaccine is controversial because of its high toxicity. Therefore, the adjuvant activity of a panel of different Toll-like receptor (TLR) agonists in combination with LPS-deficient meningococcal outer membrane complexes was compared after immunization of mice. The results demonstrate that TLR3, TLR4, TLR7, and TLR9 agonists enhance immune responses against LPS-deficient outer membrane complexes. Their adjuvant activity was characterized by higher levels of antigen-specific immunoglobulin G (IgG), IgG2a, and IgG2b; a higher IgG2a/IgG1 ratio; lower total IgE levels; and most importantly, higher serum bactericidal antibody titers compared to LPS-deficient outer membrane complexes alone.

Prediction and characterization of T-cell epitopes for epitope vaccine design from outer membrane protein of Neisseria meningitidis serogroup B

Chandra, Sharat; Singh, Digvijay; Singh, Tiratha Raj
Fonte: Biomedical Informatics Publicador: Biomedical Informatics
Tipo: Artigo de Revista Científica
Publicado em 20/09/2010 EN
Relevância na Pesquisa
66.45%
Neisseria meningitidis serogroup B (MC58) is a leading cause of meningitis and septicaemia, principally infects the infants and adolescents. No vaccine is available for the prevention of these infections because the serogroup B capsular polysaccharide is unable to stimulate an immune response, due to its similarity with polysialic acid. To overcome these obstacles, we proposed to develop a peptide based epitope vaccine from outer membrane protein contained in outer membrane vesicles (OMV) based on our computational analysis. In OMV a total of 236 proteins were identified, only 15 (6.4%) of which were predicted to be located in outer membrane. The major requirement is the identification and selection of T-cell epitopes that act as a vaccine target. We have selected 13 out of 15 outer membrane proteins from OMV proteins. Due to similarity of the fkpA and omp85 with the human FKBP2 and SAMM50 protein, we removed these two sequences from the analysis as their presence in the vaccine is likely to elicit an autoimmune response. ProPred and ProPred1 were used to predict promiscuous helper T Lymphocytes (HTL) and cytotoxic T Lymphocytes (CTL) epitopes and MHCPred for their binding affinity in N. meningitidis serogroup B (MC58), respectively. Binding peptides (epitopes) are distinguished from nonbinding peptides in properties such as amino acid preference on the basis of amino acid composition. By using this dataset...

Clonal Analysis of Neisseria meningitidis Serogroup B Strains in South Africa, 2002 to 2006: Emergence of New Clone ST-4240/6688

Moodley, Chivonne; du Plessis, Mignon; Ndlangisa, Kedibone; de Gouveia, Linda; Klugman, Keith P.; von Gottberg, Anne;
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /11/2012 EN
Relevância na Pesquisa
66.31%
From August 1999 through July 2002, hyperinvasive Neisseria meningitidis serogroup B (MenB) clonal complexes (CCs), namely, ST-32/ET-5 (CC32) and ST-41/44/lineage 3 (CC41/44), were predominant in the Western Cape Province of South Africa. This study analyzed MenB invasive isolates from a national laboratory-based surveillance system that were collected from January 2002 through December 2006. Isolates were characterized by pulsed-field gel electrophoresis (PFGE) (n = 302), and multilocus sequence typing (MLST) and PorA and FetA typing were performed on randomly selected isolates (34/302, 11%). In total, 2,400 cases were reported, with the highest numbers from Gauteng Province (1,307/2,400, 54%) and Western Cape Province (393/2,400, 16%); 67% (1,617/2,400) had viable isolates and 19% (307/1,617) were identified as serogroup B. MenB incidence remained stable over time (P = 0.77) (average incidence, 0.13/100,000 population [range, 0.10 to 0.16/100,000 population]). PFGE (302/307, 98%) divided isolates (206/302, 68%) into 13 clusters and 96 outliers. The largest cluster, B1, accounted for 25% of isolates (76/302) over the study period; its prevalence decreased from 43% (20/47) in 2002 to 13% (8/62) in 2006 (P < 0.001), and it was common in the Western Cape (58/76...

A bivalent Neisserie meningitidis recombinant lipidated factor H binding protein vaccine in young adults: results of a randomised, controlled, dose-escalation phase 1 trial

Richmond, P.; Nissen, M.; Marshall, H.; Lambert, S.; Roberton, D.; Gruber, W.; Jones, T.; Arora, A.
Fonte: Elsevier Sci Ltd Publicador: Elsevier Sci Ltd
Tipo: Artigo de Revista Científica
Publicado em //2012 EN
Relevância na Pesquisa
66.46%
Neisseria meningitidis is a leading cause of meningitis and septicaemia, but a broadly-protective vaccine against endemic serogroup B disease is not licensed and available. The conserved, outer-membrane lipoprotein factor H binding protein (fHBP, also known as LP2086) is expressed as one of two subfamily variants in virtually all meningococci. This study investigated the safety, tolerability, and immunogenicity of a recombinant-expressed bivalent fHBP (r-fHBP) vaccine in healthy adults. Participants (N=103) aged 18-25 years were recruited into three ascending dose level cohorts of 20, 60, and 200μg of a bivalent r-fHBP vaccine formulation and randomised to receive vaccine or placebo at 0, 1, and 6 months. The vaccine was well tolerated. Geometric mean titres (GMTs) for r-fHBP subfamily-specific IgG antibodies increased 19-168-fold from pre-vaccination to post-dose 2 in a dose level-dependent manner. In addition, robust serum bactericidal assay using human complement (hSBA) responses for strains expressing both homologous and heterologous fHBP variants were observed. After three vaccinations, 16-52% of the placebo group and 47-90%, 75-100%, and 88-100%, of the 20, 60, and 200μg dose levels, respectively, had seroprotective (≥ 1:4) hSBA titres against six serogroup B strains. The bivalent r-fHBP vaccine was well tolerated and induced robust bactericidal activity against six diverse serogroup B strains in young adults at the 60 and 200μg dose levels.; P.C. Richmond...

Safety, immunogenicity, and tolerability of meningococcal serogroup B bivalent recombinant lipoprotein 2086 vaccine in healthy adolescents: a randomised, single-blind, placebo-controlled, phase 2 trial

Richmond, P.; Marshall, H.; Nissen, M.; Jiang, Q.; Jansen, K.; Garces-Sanchez, M.; Martinon-Torres, F.; Beeslaar, J.; Szenborn, L.; Wysocki, J.; Eiden, J.; Harris, S.; Jones, T.; Perez, J.
Fonte: The Lancet Publishing Group Publicador: The Lancet Publishing Group
Tipo: Artigo de Revista Científica
Publicado em //2012 EN
Relevância na Pesquisa
86.48%
Background: Neisseria meningitidis serogroup B is a major cause of invasive meningococcal disease, but a broadly protective vaccine is not currently licensed. A bivalent recombinant factor H-binding protein vaccine (recombinant lipoprotein 2086) has been developed to provide broad coverage against diverse invasive meningococcus serogroup B strains. Our aim was to test the immune response of this vaccine. Methods: This randomised, placebo-controlled trial enrolled healthy adolescents from 25 sites in Australia, Poland, and Spain. Exclusion criteria were previous invasive meningococcal disease or serogroup B vaccination, previous adverse reaction or known hypersensitivity to the vaccine, any signifi cant comorbidities, and immunosuppressive therapy or receipt of blood products in the past 6 months. Participants were randomly assigned with a computerised block randomisation scheme to receive ascending doses of vaccine (60, 120, or 200 μg) or placebo at 0, 2, and 6 months. Principal investigators, participants and their guardians, and laboratory personnel were masked to the allocation; dispensing staff were not. Immunogenicity was measured by serum bactericidal assays using human complement (hSBA) against eight diverse meningococcus serogroup B strains. The co-primary endpoints were seroconversion for the two indicator strains (PMB1745 and PMB17) analysed by the Clopper-Pearson method. Local and systemic reactions and adverse events were recorded. The study is registered at ClinicalTrials.gov...

Safety and immunogenicity of a meningococcal B bivalent rLP2086 vaccine in healthy toddlers aged 18-36 months: A phase 1 randomized-controlled clinical trial

Marshall, H.; Richmond, P.; Nissen, M.; Jiang, Q.; Anderson, A.; Jansen, K.; Reynolds, G.; Ziegler, J.; Harris, S.; Jones, T.; Perez, J.
Fonte: Lippincott Williams & Wilkins Publicador: Lippincott Williams & Wilkins
Tipo: Artigo de Revista Científica
Publicado em //2012 EN
Relevância na Pesquisa
76.25%
BACKGROUND: A bivalent, recombinant, factor H–binding protein (rLP2086) vaccine was developed to protect against invasive Neisseria meningitidis serogroup B (MnB) in children and adolescents. METHODS: Healthy toddlers (N = 99) were enrolled to 3 ascending dose-level cohorts (20, 60 or 200 μg). Within each cohort (n = 33), subjects were randomized to receive an initial formulation of the bivalent rLP2086 vaccine at 0, 1 and 6 months or hepatitis A vaccine/placebo control (2:1 ratio). Reactogenicity was assessed by parental reporting of local and systemic reactions using electronic diaries and reports of unsolicited adverse events. Immunogenicity was assessed by serum bactericidal activity assay using human complement and rLP2086-specific IgG binding. RESULTS: The vaccine was considered to be well tolerated. Tenderness was the most frequently reported local reaction. Upper respiratory tract infection was the most commonly reported adverse event and occurred more frequently in the control group. Three cases (200 μg dose) of severe erythema that did not interfere with limb movement were reported. Four toddlers developed fever >40.0°C, 3 in the 200 μg group and 1 in the 60 μg group. Postdose 3, seroconversion (serum bactericidal activity assay using human complement ≥4-fold rise from baseline) was observed in 61.1–88.9% of participants against MnB strains expressing LP2086 variants homologous or nearly homologous to vaccine antigens and 11.1–44.4% against MnB strains expressing heterologous LP2086 variants. Seroconversion was observed in 77.8–100% of participants against additional...

A phase 2 open-label safety and immunogenicity study of a meningococcal B bivalent rLP2086 vaccine in healthy adults

Marshall, H.; Richmond, P.; Nissen, M.; Wouters, A.; Baber, J.; Jiang, Q.; Anderson, A.; Jones, T.; Harris, S.; Jansen, K.; Perez, J.
Fonte: Elsevier Sci Ltd Publicador: Elsevier Sci Ltd
Tipo: Artigo de Revista Científica
Publicado em //2013 EN
Relevância na Pesquisa
76.24%
BACKGROUND: Neisseria meningitidis serogroup B (MnB) is a leading cause of bacterial meningitis and septicemia in adolescents and young adults. No currently licensed and available vaccine has been shown to provide broad protection against endemic MnB disease. A bivalent rLP2086 vaccine based on two factor H-binding proteins (fHBPs) has been developed to provide broad protection against MnB disease-causing strains. METHODS: This study assessed the safety and immunogenicity of the final formulation of a bivalent rLP2086 vaccine in 60 healthy adults (18-40 years of age) receiving 120 μg doses at 0, 1, and 6 months. Safety was assessed by collecting solicited reactogenicity data and participant-reporting of adverse events. Immunogenicity was evaluated by human serum bactericidal assay (hSBA) against 5 MnB strains expressing distinct fHBP variants and fHBP-specific immunoglobulin G titre. RESULTS: After each immunisation, local reactions such as pain at the injection site and erythema were generally mild or moderate. The most common vaccine-related adverse event was upper respiratory tract infection, which was reported by two participants. Seroprotection (hSBA titres ≥ 1:4) was achieved in 94.3% of participants against a MnB strain expressing the vaccine-homologous fHBP variant A05 and 70.0%-94.7% against MnB strains expressing the heterologous fHBP variants B02...

Three-year antibody persistence and safety after a single dose of combined haemophilus influenzae type b (Hib)-Neisseria meningitidis Serogroup C-tetanus toxoid conjugate vaccine in hib-primed toddlers

Booy, R.; Richmond, P.; Nolan, T.; McVernon, J.; Marshall, H.; Nissen, M.; Reynolds, G.; Ziegler, J.; Stoney, T.; Heron, L.; Lambert, S.; Mesaros, N.; Peddiraju, K.; Miller, J.
Fonte: Lippincott Williams & Wilkins Publicador: Lippincott Williams & Wilkins
Tipo: Artigo de Revista Científica
Publicado em //2013 EN
Relevância na Pesquisa
66.45%
BACKGROUND: Persistence of seroprotective bactericidal antibody titers is important for long-term protection against meningococcal serogroup C disease in young children. Antibody persistence values were determined in children up to 3 years after vaccination with a single dose of the combined Haemophilus influenzae type b (Hib)–Neisseria meningitidis serogroup C (MenC)-tetanus toxoid (TT) conjugate vaccine (Hib-MenC-TT; www.ClinicalTrials.gov: NCT00326118). METHODS: The children had been randomized at ages 12–18 months to receive either 1 dose of Hib-MenC-TT (Hib-MenC group) or separately administered Hib-TT conjugate vaccine and MenC-CRM197 (MCC) vaccine (Hib plus MCC group). All children had been primed in infancy with a Hib vaccine. Antibodies against MenC were measured by a serum bactericidal assay using rabbit complement (rSBA-MenC) and antibodies against Hib polyribosylribitol phosphate were assessed by enzyme-linked immunosorbent assay. RESULTS: The rSBA-MenC titers >=1:8 were demonstrated 3 years after vaccination in 64.2% and 53.2% of participants in the Hib-MenC group and in the Hib plus MCC group, respectively. Antipolyribosylribitol phosphate concentrations >=0.15 µg/mL persisted in >98% of participants in both groups. The rSBA–MenC geometric mean titers and antipolyribosylribitol phosphate geometric mean concentrations remained higher 3 years after vaccination than before vaccination. No serious adverse events assessed by the investigator as being related to vaccination were reported. CONCLUSION: In this antibody persistence study of Hib-primed but MenC-naïve toddlers who received a single dose of Hib-MenC-TT...

A randomized, controlled, phase 1/2 trial of a Neisseria meningitidis serogroup B bivalent rLP2086 vaccine in healthy children and adolescents

Nissen, M.; Marshall, H.; Richmond, P.; Jiang, Q.; Harris, S.; Jones, T.; Jansen, K.; Perez, J.
Fonte: Lippincott Williams & Wilkins Publicador: Lippincott Williams & Wilkins
Tipo: Artigo de Revista Científica
Publicado em //2013 EN
Relevância na Pesquisa
96.39%
BACKGROUND: Neisseria meningitidis serogroup B (MnB) is a significant cause of invasive meningococcal disease. Factor H binding protein (also known as LP2086) is a conserved outer membrane neisserial lipoprotein that has emerged as a strong candidate protein antigen for MnB vaccination. This study examined the safety, tolerability and immunogenicity of an initial formulation of a bivalent recombinant LP2086 (rLP2086) vaccine in healthy children and adolescents. METHODS: In this randomized, observer-blinded, parallel-group, multicenter trial conducted at 6 centers in Australia, 127 healthy participants aged 8-14 years were assigned to receive 20, 60 or 200 µg of the bivalent rLP2086 vaccine (n = 16, 45 and 45, respectively) or active control (Twinrix, n = 21) at 0, 1 and 6 months. Immunogenicity was assessed before the first dose and 1 month after doses 2 and 3. Local reactions, systemic events and other adverse events were recorded. The primary immunogenicity endpoint was the rate of seroconversion (≥4-fold rise in human complement serum bactericidal assay titer) against MnB strains expressing the homologous A05 or heterologous B02 LP2086 variants. RESULTS: The bivalent rLP2086 vaccine was generally well-tolerated, with mostly mild to moderate local reactions. The most common adverse events...

Molecular subtyping of Neisseria meningitidis serogroup B: comparison of five methods.

Swaminathan, B; Matar, G M; Reeves, M W; Graves, L M; Ajello, G; Bibb, W F; Helsel, L O; Morales, M; Dronavalli, H; el-Swify, M; DeWitt, W; Hunter, S B
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /06/1996 EN
Relevância na Pesquisa
76.41%
In order to compare methods for subtyping Neisseria meningitidis serogroup B isolates, 96 isolates obtained from various locations in the United States and northwestern Europe were subtyped by five methods: monoclonal antibody (MAb)-based serotyping and serosubtyping, DNA macrorestriction analysis by pulsed-field gel electrophoresis (PFGE), multilocus enzyme electrophoresis (MEE), ribotyping, and PCR-restriction fragment length polymorphism of the internally transcribed spacer region of the rRNA operon (ITS PCR-RFLP). All N. meningitidis serogroup B isolates were typeable by PFGE, MEE, ribotyping, and ITS PCR-RFLP. Only 44.8% of the isolates were completely typeable (both serotype and serosubtype determination) by MAb-based serotyping and serosubtyping. 60.4% of the isolates could be serotyped but not serosubtyped, and 90.6% of the isolates could be either serotyped or serosubtyped. Simpson's discrimination indices of diversity for the methods were as follows: PFGE, 99.7%; MEE, 99.4%; ribotyping, 98.8%; MAb serotyping, 75.8%; MAb serotyping and/or serosubtyping 97.5%; and ITS PCR-RFLP, 84.2%. The high degree of diversity observed by PFGE, MEE, and ribotyping can be explained by the fact that isolates were collected from different geographic locations at various times. PFGE...

Production of outer membrane vesicles (OMV) in batch cultivation of Neisseria meningitidis serogroup B

Santos,Silvia; Baruque-Ramos,Júlia; Tanizaki,Marta Massako; Lebrun,Ivo; Schenkman,Rocilda Perazzini Furtado
Fonte: Sociedade Brasileira de Microbiologia Publicador: Sociedade Brasileira de Microbiologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2006 EN
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Meningococcal disease is an important cause of death and morbidity throughout the world. Nearly 330,000 cases and 35,000 deaths occur yearly. Neisseria meningitidis, serogroup B strain N.44/89, is prevalent in Brazil. Its outer membrane vesicles (OMV) with iron regulated proteins (IRP) are released to the culture medium and are used as antigen for vaccine production. In order to have knowledge about the kinetic parameters, especially the final OMV concentration values, 20-h batch cultivations were carried out in Catlin medium with iron restriction. Process conditions comprised: 7 L bioreactor, 36ºC, 0.5 atm, overlay air flowrate of 1 L/min, agitation varying from 250 rpm to 850 rpm and dissolved oxygen control set at 10% of saturation condition. Biomass was determined by optical density at 540 nm and dry weight. Glycerol, lactate, pH and dissolved oxygen were measured from samples taken during cultivation. Outer membrane vesicle (OMV) concentration was determined by Lowry's method after ultracentrifugation. IRP presence was verified by SDS-PAGE. Highest biomass value, corresponding to the highest initial lactate concentration (7.84 g/L) was achieved at the 9th hour process time corresponding to 1.0 g/L dry biomass and 2.3 optical density at 540 nm. Lactate consumption was directly related to cell growth (yield factor: 0.24 g dry biomass / g lactate). Glycerol concentration in the medium did not change significantly during the process. OMV concentration reached the highest value of 80 mg/L at end cultivation time. The obtained results suggest that lactate is a main limiting growth factor and the maximum amount of antigen is obtained during stationary growth and cell death phases.

Relação genética entre cepas de Neisseria meningitidis sorogrupo B sorotipo 4; Genetic relationships among serogroup B: serotype 4 Neisseria meningitidis strains

LEMOS, Ana Paula S.; SACCHI, Claudio T.; PAIVA, Maria V.; YARA, Teresa I.; MELLES, Carmo Elias A.; MAYER, Leonard W.
Fonte: Universidade de São Paulo. Instituto de Medicina Tropical de São Paulo Publicador: Universidade de São Paulo. Instituto de Medicina Tropical de São Paulo
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; ; ; Formato: application/pdf
Publicado em 01/06/2001 ENG
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We compared the results obtained by serotyping of PorB epitopes using an expanded panel of monoclonal antibodies (mAb) including mAb 7 and mAb 10, with results obtained by RFLP of rRNA genes (ribotyping). The purpose of this study was to assess the correlation between phenotypic- and genotypic- methods for typing N. meningitidis. The ribotypes obtained using ClaI or EcoRV endonucleases grouped the strains in seven and two different patterns, respectively. This additional characterization of PorB epitopes improved the correlation between these two methods of typing N. meningitidis.; Nós comparamos os resultados obtidos pela sorotipagem usando um painel de anticorpos monoclonais (mAb) ao qual se incluíam os mAbs 7 e 10, com os resultados obtidos pelo RFLP do gene rRNA (ribotipagem). O propósito deste estudo foi avaliar a correlação entre os métodos fenotípico e genotípico de tipagem de N. meningitidis. Os ribotipos obtidos usando as endonucleases de restrição ClaI e EcoRV foram hábeis em dividir as cepas em sete e dois diferentes perfis de restrição, respectivamente. A caracterização adicional de epítopos na proteína PorB melhorou a correlação entre os dois métodos de tipagem de N. meningitidis.