Meningococcal vaccines.
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Bacterial Outer Membrane Proteins↗
Biomedical subjects
J T Poolman
Publications and source records attributed to J T Poolman.
Typing of group-B Neisseria meningitidis with monoclonal antibodies in the whole-cell ELISA.
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Antibodies, Monoclonal↗
Correlation of serological typing and clonal typing methods for Neisseria meningitidis sero-group A.
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Antibodies, Monoclonal↗
Development of IgG antipolyribosylribitolphosphate antibodies in the course of H. influenzae type b meningitis in infants below 2 years of age.
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Antibody Formation↗
Comparison of meningococcal outer membrane protein vaccines solubilized with detergent or C polysaccharide.
Outer membrane proteins (OMPs) were isolated from meningococcal strain H44/76 (B:15:P1.16) by detergent extraction of bacteria. A final product containing class 1 (P1.16), 3(15), 4 OMPs and 5% (w/w) lipooligosaccharide was obtained. Two experimental vaccines were prepared: OMP-detergent and OMP-C polysaccharide. The OMP-detergent vaccine tended to show a better bactericidal: ELISA ratio for the antibodies induced as compared to the OMP-C polysaccharide vaccine. The vaccine induced bactericidal antibodies appeared for the greater part to be directed against the class 1 OMP (P1.16). By comparison of cultures grown in Mueller Hinton Broth with and without 0.25% (w/v) glucose, it was found that monoclonal antibodies against the serotype OMP (class 2 or 3) were not bactericidal against meningococci grown in MHB without glucose. Antibodies against class 1 OMP and lipooligosaccharide were not influenced by this. A new major outer membrane protein (appr. 40 kd) is described that may function as a cation-specific porin.
Animals↗
Differential expression of "Fe-repressible" and "growth-rate-sensitive" proteins in Neisseria meningitidis and Neisseria gonorrhoeae.
By varying growth conditions, we were able to differentiate (SDS-PAGE) between true "Fe-repressible" proteins and "growth-rate-sensitive" proteins (GSP's) (60-110 Kd) in outer membranes of iron-starved meningococci and gonococci. Immunological characterization with monoclonal antibodies raised against the GSP's revealed (GIRA) crossreactivity between different GSP's. On the basis of common epitopes, two groups of proteins could be distinguished. Immuno-electron-microscopy showed that proteins of both groups were exposed at the cell surface.
Antibodies, Monoclonal↗
Protective efficacy of monoclonal antibodies to class 1 and class 3 outer membrane proteins of Neisseria meningitidis B:15:P1.16 in infant rat infection model: new prospects for vaccine development.
The protective efficacy of monoclonal antibodies to class 1 and class 3 outer membrane proteins of Neisseria meningitidis B:15:P1.16 was tested in an infant rat infection model. Four monoclonal antibodies to class 1 protein had bactericidal titres exceeding 20,000 and they protected infant rats completely against bacterial challenge with meningococci carrying the same class 1 protein, P1.16. One monoclonal antibody to class 3 protein was highly bactericidal (titer greater than 20,000), whereas two others had no bactericidal activity. All these antibodies gave some protection from infection, resulting in mortalities varying from 66 to 83% as compared to 100% in control rats who had received either unrelated monoclonal antibody or saline. These results strongly speak for class 1 outer membrane protein as a vaccine candidate for meningococcus group B.
Animals↗
Meningococcal serotypes and serogroup B disease in north-west Europe.
Examination of the trends of meningococcal infection in Norway, Iceland, Faroe Islands, Denmark, England and Wales, and the Netherlands, has shown that Neisseria meningitidis B:2b:P1.2 and/or B:2a:P1.2 phenotypes were associated with peaks of infection in the Netherlands in 1966, in Iceland 1976-77, and in England and Wales in 1973-75. These strains were present in all six countries in the decade 1970-80 but their prevalence is now practically negligible. In contrast the prevalence of the B:15:P1.16 phenotype has risen. In the Faroe Islands and northern Norway this change in serotype prevalence has been followed by rises in incidence of meningococcal disease; the same is happening in England and Wales but not yet in the other countries.
Adult↗
Meningococcal disease in The Netherlands, 1959-1981: the occurrence of serogroups and serotypes 2a and 2b of Neisseria meningitidis.
By means of a filter radioimmunoassay and the use of monoclonal anti-2a and anti-2b antibodies, we have serotyped 3164 of 3688 strains of Neisseria meningitidis isolated from patients in The Netherlands between 1959 and 1981. Serotypes 2a and 2b were distributed differently among the major serogroups A, B, C, and W-135. Neither of the types was found among group A strains. Type 2b strains of serogroup B emerged in 1965, causing a country-wide epidemic which reached a peak incidence in March and April of 1966 and continued to predominate within group B until 1979. Type 2a strains of serogroup C were responsible for a substantial number of sporadic cases over a long period without any association with outbreaks or with a shift in the pattern of the serogroup. After the appearance of group W-135 in 1971, W-135 strains caused a small non-focal epidemic wave. The upsurge of disease due to virulent sub-populations of strains B:2b and C:2a appeared to be closely related to a basic pattern of regular cyclical waves with peak intervals which differed for serogroups A, B, and C. In recent years both serotype 2a and 2b strains within the different serogroups fell to insignificant numbers. Our results show that retrospective large-scale serotyping of collected strains provides insight into the epidemiological patterns of endemic meningococcal disease.
Antibodies, Bacterial↗
Class 1/3 outer membrane protein vaccine against group B, type 15, subtype 16 meningococci.
Neisseria meningitidis capsular polysaccharides and outer membrane proteins have been incorporated in vaccines and the potential of these vaccines has been evaluated in man. Polysaccharides are the most attractive candidates for a vaccine against group A and C meningococci whereas outer membrane proteins may have a potential for a vaccine against group B meningococci. This paper describes the characteristics of the five classes of outer membrane proteins of group B meningococci and the protective (bactericidal) activity of monoclonal antibodies against class 1 and 2 or 3 outer membrane proteins. Monoclonal antibodies against class 1 outer membrane proteins were bactericidal irrespective of the growth conditions of the bacterium. On the other hand, these conditions influenced the bactericidal activity of monoclonal antibodies against class 2 or 3 outer membrane proteins. These data indicate that class 1 outer membrane protein is an attractive component of a vaccine. The Blake and Gotschlich procedure for the isolation of gonococcal outer membrane protein II (1) was adapted for the isolation of a combination of class 1 and 3 outer membrane proteins from group B, type 15 meningococci. The combination of both outer membrane proteins was adsorbed to ALPO4 in the presence of the detergent Zwittergent 3-14. The vaccine was injected into mice. The antibodies were strongly bactericidal and Western blot analysis indicated that both outer membrane proteins induced antibodies. The vaccine may have a potential to combat an epidemic caused by group B, type 15 meningococci. Such an epidemic was observed in some N.W. - European countries.
Animals↗
Disseminated gonococcal infection in elderly patients.
Four elderly patients (71, 53, 57, and 62 years old) had disseminated gonococcal infection. Three patients presented with suppurative arthritis and the fourth with fever, skin lesions, and malaise. Although the signs and symptoms did not differ from those in the younger age group, the diagnosis was not considered clinically. All gonococci were susceptible to penicillin.
Age Factors↗
Colony variants of Neisseria meningitidis strain 2996 (B:2b:P1.2): influence of class-5 outer membrane proteins and lipopolysaccharides.
Different colonial morphologies were found among colonies of Neisseria meningitidis strain 2996 (B:2b:P1.2). Examination of cultures, selected on the basis of colony transparency or opacity, revealed that both lipopolysaccharides (LPS) and class-5 outer membrane proteins (OMP) are associated with differences in colonial morphology. Among 13 variants, four LPS variants and two class-5 OMP variants were recognised. All variants were non-fimbriate. The LPS variations were confirmed by immunoprecipitation. In addition to these qualitative variations of LPS, meningococci synthesise LPS of different molecular size depending upon growth phase; larger LPS molecules were found after analysis of stationary-phase cultures than with exponential-phase cultures. These changes did not cause a change in serotyping characteristics. The recognition in this study of intra-strain heterogeneity of meningococcal LPS and class-5 OMPs is important for the understanding of meningococcal pathogenicity. This heterogeneity was also detected in simultaneous isolates from different sites of a patient.
Bacterial Outer Membrane Proteins↗
Monoclonal antibody activity against native and denatured forms of gonococcal outer membrane proteins as detected within ultrathin, longitudinal slices of polyacrylamide gels.
Monoclonal antibodies were used to analyze the antigenic properties of denatured and native forms of gonococcal outer membrane proteins. The protein samples were only partially dissociated by treatment for 30 min at 40 degrees C with 0.1% (w/v) SDS, 0.5% (v/v) Triton X-100, and then processed by polyacrylamide gel electrophoresis without boiling. The resulting pattern included the native aggregated and trimeric forms of protein I and III as they exist in the gonococcal outer membrane, as well as the denatured monomeric forms. Two methods were compared to analyze these gels: gel immunoradioassay (GIRA), and Western blotting. With GIRA longitudinal 50 micron thin slices, up to 40 identical copies per gel, were produced with a microtome cryostat. These slices were exposed to the monoclonal antibody and antibody binding was detected by 125I-protein A and autoradiography. Serotype-specific, monoclonal antibodies reacted most commonly with the native polymeric form of gonococcal protein I and less frequently recognized the denatured, monomeric form. Monoclonal antibodies that recognized the polymeric form of protein I frequently produced antibody-mediated, complement-dependent, bactericidal activity for gonococci bearing the same protein I serotype. The antigen specificity of these functionally relevant antibodies could not be characterized by the Western blotting procedure, which produced incomplete transfer to nitrocellulose paper of the polymeric, high molecular weight protein aggregates. A third technique, radioimmunoprecipitation using partial dissociating conditions, did not permit differentiation between proteins I- and III-specific monoclonals after analysis of the precipitated material by denaturing SDS electrophoresis.
Animals↗
Filter radioimmunoassay, a method for large-scale serotyping of Neisseria meningitidis.
A simple and rapid filter radioimmunoassay method can be used to serotype meningococcal strains on a large scale. The technique consists of simultaneous inoculation of 96 strains on nitrocellulose filters. The resulting colonies can be processed in situ, by extraction and fixation, incubation with antibodies and 125I-labeled protein A, and, finally, autoradiography. Processing many filters simultaneously, one person can serotype thousands of meningococci in a week. Multiple filters with identical strain patterns can be stored after the fixation step for future screening. The use of monoclonal antibodies is essential; polyclonal antisera, even after extensive absorption, were not specific in this assay. When results from filter radioimmunoassay and Ouchterlony microprecipitation were compared for the serotyping of 201 Neisseria meningitidis strains for serotypes 2a and 2b, filter radioimmunoassay was sufficiently sensitive and specific to be useful in mass screening.
Antibodies, Bacterial↗
Immunogenicity of meningococcal antigens as detected in patient sera.
The immunogenicity of meningococcal surface antigens was tested in acute- and convalescent-phase sera from patients with meningococcal diseases by enzyme-linked immunosorbent assay and gel immunoradioassay. In gel immunoradioassay, the antigens are separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis before testing their antibody-binding capacity. Both 125I-labeled protein A and 125I-labeled anti-human immunoglobulin G were used to detect antibody binding. It appeared that the variable, low-molecular-weight, heat-modifiable major outer membrane proteins (molecular weights, 25,000 to 32,000) induced strong, strain-specific immunoglobulin G antibody responses. In addition, pili induced strong, cross-reactive antibody responses that could be detected with 125I-labeled protein A, but not with 125I-labeled anti-immunoglobulin G. Antibody responses against capsular polysaccharides, lipopolysaccharides, and minor outer membrane proteins could also be detected by gel immunoradioassay. When tested by enzyme-linked immunosorbent assay against outer membrane complexes, patient sera demonstrated a large amount of cross-reactivity against heterologous meningococcal strains.
Acute Disease↗
Immunochemical characterization of Neisseria meningitidis serotype antigens by immunodiffusion and SDS-polyacrylamide gel electrophoresis immunoperoxidase techniques and the distribution of serotypes among cases and carriers.
The chemical nature of the antigens of the meningococcal serotypes described by Frasch and colleagues was determined by a combination of immunodiffusion and the SDS-polyacrylamide gel electrophoresis immunoperoxidase technique (SGIP). It was confirmed that the serotype antigens of the outer membrane of serotypes 1, 2, 6, 9, 11 and 12 were proteins, whilst those of serotypes 4,5 and 8 were lipopolysaccharides. Serotype 2 can now be divided into three related types, provisionally called 2a (originally serotype 2), 2b and 2c with the specific antigens being proteins having molecular weights of 41,000, 41,500 and 41,500, respectively. A total of 195 strains of meningococci isolated from patients and carriers in the Netherlands and 20 serogroup Y strains from patients in the U.S.A. were serotyped by means of immunodiffusion. Serotype 2a could be demonstrated in some strains belonging to the serogroups B (only those from carriers), C, W-135 and Y (only those from the U.S.A.). The W-135 strains isolated from patients in this series more often belonged to serotype 2a than did the W-135 strains from carriers. Serotype 2b was present in about half of the serogroup B and a few serogroup C strains isolated from patients with meningitis, but absent in serogroup B and C strains from carriers. Serotype 2c could only be demonstrated in serogroup Y strains, both from the Netherlands and the U.S.A. The other serotypes were found only sporadically.
Antigens, Bacterial↗
Variability of low-molecular-weight, heat-modifiable outer membrane proteins of Neisseria meningitidis.
Analysis of major outer membrane protein (MOMP) profiles of various meningococci by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis (SDS-PAGE) revealed the presence of 0 to 2 low-molecular-weight, heat-modifiable MOMPs (molecular weight, 25,000 to 32,000) and 1 to 3 high-molecular-weight MOMPs (molecular weight, 32,000 to 46,000). Heat modifiability was investigated by comparing MOMP profiles after heating in SDS solutions at 100 degrees C for 5 min or at 40 degrees C for 1 h. Low-molecular-weight MOMPs shifted to higher apparent molecular weights after being heated at 100 degrees C. Heat modifiability of high-molecular-weight MOMPs varied among strains; whenever modified these proteins shifted to lower apparent molecular weights after complete denaturation. Variability of low-molecular-weight, heat-modifiable MOMPs was demonstrated when MOMP profiles were compared of (i) isolates from index cases and associated cases and carriers among contacts, (ii) different isolates from the same individual, and (iii) isolates from a small epidemic caused by serogroup W-135. In some cases high-molecular-weight MOMPs revealed quantitative differences among related strains. The observed variability and quantitative differences indicate that MOMP serotyping and typing on the basis of SDS-PAGE profiles (PAGE typing) need careful reevaluation.
Adolescent↗
Application of cystamine and N,N'-Bis(glycyl)cystamine as linkers in polysaccharide-protein conjugation.
Pneumococcal polysaccharide type 6B, 14, or 23F (35-70 kDa) was activated with cyanogen bromide and modified with cystamine. After reduction of the spacer, the thiol-containing (i.e. cysteamine-modified) polysaccharide obtained was added in a 5-10-fold molar excess to bromoacetylated tetanus toxoid to give thioether-linked polysaccharide-protein conjugates in a yield of 10-20%. This approach failed for preparing a type 19F polysaccharide-protein conjugate, possibly due to intramolecular elimination of cysteamine from the reduced 19F polysaccharide. When N,N'-bis(glycyl)cystamine was introduced as a spacer molecule, the elimination of the reduced spacer was suppressed, thus allowing preparation of a 19F polysaccharide-tetanus toxoid conjugate (15%).
Carbohydrate Conformation↗