| immunogenicity of conjugate vaccines consisting of pneumococcal capsular polysaccharide types 6b, 14, 19f, and 23f and a meningococcal outer membrane protein complex. | in an effort to prepare pneumococcal (pn) capsular polysaccharide (ps) vaccines that would be immunogenic in infants, covalent conjugates were prepared for pn types 6b, 14, 19f, and 23f. each ps type was covalently bound to an outer membrane protein complex from neisseria meningitidis serogroup b and evaluated for immunogenicity in mice and infant monkeys. the conjugates induced specific anti-ps antibody responses in mice and in infant rhesus and african green monkeys; a conjugate of 6b and oute ... | 1992 | 1452327 |
| a vaccine carrier derived from neisseria meningitidis with mitogenic activity for lymphocytes. | protein carriers vary in their ability to increase the immunogenicity of poorly immunogenic or t-lymphocyte-independent antigens. we examined one such carrier, the outer membrane protein complex derived from neisseria meningitidis serogroup b strain b11, in an attempt to determine why this outer membrane protein complex was more immunogenic in young infants and in relevant animal models than two other carriers used in conjugates made with haemophilus influenzae type b polysaccharide, a t-cell-in ... | 1992 | 1533934 |
| specificity of the immune response to the group b polysaccharide of neisseria meningitidis. | a panel of monoclonal antibodies (mab) and polyclonal sera of murine, human and equine origin, of igm isotype and with specificity for neisseria meningitidis group b polysaccharide, an alpha(2----8)-linked homopolymer of sialic acid, were examined for their antigenic and biological specificities. the nature of the antigenic determinants on b polysaccharide was investigated using a series of n-acyl derivatives of b polysaccharide, two sialic acid polymers containing alpha(2----9)-linkages and a s ... | 1991 | 1722773 |
| rapid detection of bacteria in cerebrospinal fluid by immunofluorescence staining on membrane filters. | a filter-fluorescent-antibody (ffa) staining procedure was developed for detection of bacteria in cerebrospinal fluid (csf). the sensitivity of this procedure was determined and compared with that of the slide gram stain of centrifuged samples, latex agglutination, and a previously developed filter gram stain. serial 10-fold dilutions of filter-sterilized csf seeded with logarithmic-phase organisms were examined by each method and cultured to determine colony-forming bacteria. the bacteria inclu ... | 1990 | 2185258 |
| immunoresponses to neisseria meningitidis epitopes: suppression of secondary response to phosphorylcholine is carrier specific. | results of our previous work have shown that neisseria meningitidis serogroup b m986 can induce a phosphorylcholine (pc)-specific plaque-forming cell immunoresponse in mice. also, a single injection of a relatively low dose of meningococci in nbf1 female mice induced a priming time-dependent suppression on subsequent meningococcus challenge. this suppression was not due to switching to another class of immunoglobulin nor to the presence of a capsule on n. meningitidis. in this study we show that ... | 1986 | 2416688 |
| purification and characterization of h.8 antigen from group b neisseria meningitidis. | the surface antigen (h.8) common to the pathogenic neisseria species was purified by a simple procedure by use of high-performance liquid chromatography. the purified h.8 antigen was characterized as to its amino acid composition, susceptibilities to several proteolytic enzymes, isoelectric point, and susceptibilities to an acid and a base. the amino acid composition of purified h.8 antigen from two strains of neisseria meningitidis group b, namely, 44/76 and 8047, were compared. it was found th ... | 1988 | 2450067 |
| molecular characterization and expression in escherichia coli of the gene complex encoding the polysaccharide capsule of neisseria meningitidis group b. | the gene complex encoding all determinants of the biosynthesis pathway of the capsule of group b meningococci (cps) has been cloned in escherichia coli. a 24-kilobase large chromosomal fragment is necessary for capsule expression on the e. coli surface. by transposon and deletion mutagenesis, two separate steps in transport of the polysaccharide from the cytoplasm to the periplasm and further to the cell surface became evident. mutants were also isolated that accumulate soluble poly(sialic acid) ... | 1989 | 2493648 |
| immunoresponses to neisseria meningitidis epitopes: primary versus secondary antiphosphorylcholine responses. | specific antiphosphorylcholine immune responses were found to be elicited by different neisseria meningitidis group b m986 preparations. our results suggest the functional presence of phosphorylcholine in the bacteria. the immune responses, mostly immunoglobulin m, were measured with a plaque-forming cell assay. the secondary phosphorylcholine-specific immune response induced by intact meningococci was significantly lower than the primary phosphorylcholine-specific immune response induced by the ... | 1985 | 2580791 |
| murine monoclonal antibodies for detection of antigens and culture identification of neisseria meningitidis group b and escherichia coli k-1. | four murine monoclonal antibodies which reacted with a (2----8)alpha-linked sialic acid polysaccharide were produced. three of the antibodies reacted specifically with neisseria meningitidis serogroup b and escherichia coli k-1 polysaccharide antigens, whereas one antibody cross-reacted with n. meningitidis group c polysaccharide antigen, a (2----9)alpha-linked homopolymer of sialic acid. by using the most avid antibody (mb 62), a latex particle agglutination test was developed which could detec ... | 1987 | 3116036 |
| neisseria meningitidis in a primary school. | a prospective study of the nasopharyngeal carriage of sulphonamide resistant neisseria meningitidis, group b, type 15 p1.16, was undertaken after a cluster of four cases of meningococcal infections had occurred, two of which were fatal, during a three year period among children attending an inner london primary school. throughout the year of the study the overall carriage and acquisition rates of meningococci were less than 6% and 1%, respectively, and were no different from those of control chi ... | 1987 | 3120654 |
| rapid identification of bacterial antigen in blood cultures and cerebrospinal fluid. | the ability of antibody coated latex particle suspensions to aid the diagnosis of septicaemia and meningitis in children was assessed in 272 blood culture sets and 85 cerebrospinal fluid specimens. this was also assessed in cases caused by neisseria meningitidis group b infection. the method was 100% sensitive and 99% specific, with good predictive values (range 63% to 100%) and provided valuable support to the routine bacteriological examination of blood culture and cerebrospinal fluid. | 1988 | 3385001 |
| immunity and protection of mice against neisseria meningitidis group b by vaccination, using polysaccharide complexed with outer membrane proteins: a comparison with purified b polysaccharide. | a methodology for preparing outer membrane proteins (type specific) complexed to group b polysaccharide of neisseria meningitidis is described. these complexes, low in nucleic acid and lipopolysaccharide content, were immunogenic in mice with induction of humoral antigroup b and antiprotein responses. immunized mice were also protected against challenge with n. meningitidis group b strains of the same or a different type from that used for vaccination. both immunity and protection were enhanced ... | 1985 | 3917979 |
| role of lipid intermediate(s) in the synthesis of serogroup b neisseria meningitidis capsular polysaccharide. | neisseria meningitidis serogroup b strain m986 was examined for the involvement of lipid intermediate(s) participating in the biosynthesis of the sialic acid capsular polysaccharide. the addition of exogenous undecaprenyl phosphate, phosphatidylethanolamine, or phosphatidylglycerol to particulate membranes, in the presence of cytidine 5'-monophosphosialic acid, resulted in the stimulation of sialyltransferase activity specifically by undecaprenyl phosphate. sialyltransferase activity, after deli ... | 1985 | 3918990 |
| protection against infection with neisseria meningitidis group b serotype 2b by passive immunization with serotype-specific monoclonal antibody. | hybridomas derived from mice immunized with neisseria meningitidis serogroup b serotype 2b (b,2b) outer membrane preparations produced monoclonal antibodies (mabs) specific for major outer membrane proteins of classes 1, 2, and 5. the mabs were examined by enzyme-linked immunosorbent assay against a selected panel of seven strains of n. meningitidis (b,2b) of different sodium dodecyl sulfate-polyacrylamide gel electrophoresis patterns, a serotype 2a, and a nontypable strain. the five mabs select ... | 1985 | 3932211 |
| physiology of sialic acid capsular polysaccharide synthesis in serogroup b neisseria meningitidis. | the pathway for biosynthesis of sialic acid capsular polysaccharide was examined in neisseria meningitidis serogroup b strain m986 and in strain prm102, an isogenic mutant defective in polysaccharide production. strain prm102 was found to possess only 25% of the level of sialyltransferase activity that was found in strain m986, but it had wild-type levels of both the n-acetylneuraminic acid (nana) condensing enzyme and the cmp-nana synthetase. a new meningococcal enzyme, a cmp-nana hydrolase, wa ... | 1983 | 6302082 |
| cloning and analysis of the k1 capsule biosynthesis genes of escherichia coli: lack of homology with neisseria meningitidis group b dna sequences. | genes coding for production of the k1 polysaccharide capsule of escherichia coli have been cloned. complementation, insertion, and deletion analyses were used to localize the k1 genes and demonstrated that a minimum of 9 kilobases of dna split into at least two gene blocks is involved in synthesis and assembly of the capsule. one of the gene blocks is responsible for biosynthesis of the polysaccharide, and the other is responsible for extracellular appearance of capsular material. using cloned k ... | 1983 | 6408005 |
| development of a neisseria meningitidis group b serotype 2b protein vaccine and evaluation in a mouse model. | although serotype 2 remains the predominant cause of group b neisseria meningitidis disease in many parts of the world, most cases of this disease are now due to serotype 2b rather than 2a. for this reason, we adapted the serotype 2a vaccine method of c. e. frasch and m. s. peppler (infect. immun. 37:271-280, 1982) to the production of a serotype 2b protein vaccine. a spontaneously occurring nonencapsulated mutant of the group b serotype 2b strain 3006 was obtained by selection on group b antise ... | 1984 | 6437983 |
| increased virulence of neisseria meningitidis after in vitro iron-limited growth at low ph. | at low ph (6.6) and under conditions of iron limitation, neisseria meningitidis group b (strain sd1c) exhibited an atypical outer membrane protein profile and an increased relative virulence for the mouse. cells grown in a buffered medium were effectively deprived of iron by the addition of ethylenediamine-diorthohydroxyphenylacetate. the ph of the medium selected for characteristic colonial morphologies: type m3 predominated at ph 6.6, and type m5 predominated at ph 7.7. a mixed population of m ... | 1981 | 6790443 |
| human immunoglobulin m paraproteins cross-reactive with neisseria meningitidis group b polysaccharide and fetal brain. | three hundred fifty-nine serum samples from patients with immunoglobulin m (igm) or igg monoclonal gammopathies were tested for binding to the capsular polysaccharide (ps) of neisseria meningitidis group b (menb ps, poly-alpha[2-->8]-n-acetylneuraminic acid). of 159 igm paraproteins, 7 (4.4%) were positive, compared with 0 of 200 igg paraproteins (p < 0.05). since menb ps reactivity was limited to the igm paraproteins, the 159 igm paraproteins were tested by enzyme-linked immunosorbent assay (el ... | 1995 | 7729901 |
| nucleotide sequence and genetic analysis of the neud and neub genes in region 2 of the polysialic acid gene cluster of escherichia coli k1. | the k1 capsular polysaccharide, a polymer of sialic acid, is an important virulence determinant of extraintestinal pathogenic escherichia coli. the genes responsible for the synthesis and expression of the polysialic acid capsule of e. coli k1 are located on the 17-kb kps gene cluster, which is functionally divided into three regions. central region 2 encodes proteins necessary for the synthesis, activation, and polymerization of sialic acid, while flanking regions 1 and 3 are involved in polyme ... | 1995 | 7814319 |
| current status of meningococcal group b vaccine candidates: capsular or noncapsular? | meningococcal meningitis is a severe, life-threatening infection for which no adequate vaccine exists. current vaccines, based on the group-specific capsular polysaccharides, provide short-term protection in adults against serogroups a and c but are ineffective in infants and do not induce protection against group b strains, the predominant cause of infection in western countries, because the purified serogroup b polysaccharide fails to elicit human bactericidal antibodies. because of the poor i ... | 1994 | 7834605 |
| ribotyping as an additional molecular marker for studying neisseria meningitidis serogroup b epidemic strains. | 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 ch ... | 1994 | 7852566 |
| role of neutrophil fc gamma riia (cd32) and fc gamma riiib (cd16) polymorphic forms in phagocytosis of human igg1- and igg3-opsonized bacteria and erythrocytes. | the four subclasses of igg have different biological activities associated with their fc regions. fc gamma receptors on leucocytes (fc gamma r) mediate binding and phagocytosis of opsonized particles. two structurally and functionally distinct allelic polymorphisms of the fc gamma r have been defined: the h/r131 forms of fc gamma riia (cd32), and the neutrophil antigen 1 (na1)/na2 forms of fc gamma riiib (cd16). in this study the activities of allotypes of cd16 are analysed with antibacterial ig ... | 1994 | 7875742 |
| immune response of brazilian children to a neisseria meningitidis serogroup b outer membrane protein vaccine: comparison with efficacy. | since 1986, serogroup b neisseria meningitidis has caused approximately 80% of the meningococcal disease in brazil. in 1988, an epidemic caused by n. meningitidis b:4:p1.15 was recognized in the greater são paulo area of brazil. the são paulo state government decided to vaccinate children from 3 to 83 months of age with a vaccine consisting of serotype 4 outer membrane protein and group c meningococcal polysaccharide that was produced in cuba. about 2.7 million children were vaccinated during tw ... | 1994 | 7927704 |
| molecular cloning and analysis of genes for sialic acid synthesis in neisseria meningitidis group b and purification of the meningococcal cmp-neunac synthetase enzyme. | the gene encoding for the cmp-neunac synthetase enzyme of neisseria meningitidis group b was cloned by complementation of a mutant of escherichia coli defective for this enzyme. the gene (neua) was isolated on a 4.1-kb fragment of meningococcal chromosomal dna. determination of the nucleotide sequence of this fragment revealed the presence of three genes, termed neua, neub, and neuc, organized in a single operon. the presence of a truncated ctra gene at one end of the cloned dna and a truncated ... | 1994 | 8045888 |
| variable region sequences and idiotypic expression of a protective human immunoglobulin m antibody to capsular polysaccharides of neisseria meningitidis group b and escherichia coli k1. | we determined the heavy (h)- and light (l)-chain variable (v) region nucleotide and translated amino acid sequences of the human immunoglobulin m(kappa) monoclonal antibody (mab) 5e1, which is specific for the polysaccharide capsule of escherichia coli k1 and neisseria meningitidis group b (poly[alpha(2-->8)-n-acetylneuraminic acid]) and which is protective in animal models of infection. the 5e1 vh gene is a member of the vhiiib family and is 97% homologous to the 9.1 germ line gene. the 5e1 vl ... | 1994 | 8168940 |
| cloning, sequencing, expression, and complementation analysis of the escherichia coli k1 kps region 1 gene, kpse, and identification of an upstream open reading frame encoding a protein with homology to gutq. | the kps locus for polysialic acid capsule expression in escherichia coli k1 is composed of a central group of biosynthetic neu genes, designated region 2, flanked on either side by region 1 or region 3 kps genes with poorly defined functions. chromosomal mutagenesis with mudj and subsequent complementation analysis, maxicell and in vitro protein expression studies, and nucleotide sequencing identified the region 1 gene, kpse, which encodes a 39-kda polypeptide. polarity of the kpse::lacz mutatio ... | 1993 | 8253690 |
| neuraminic acid is alpha 2-->3 linked in the lipooligosaccharide of neisseria meningitidis serogroup b strain 6275. | we have analyzed the sialylated lipooligosaccharide of neisseria meningitidis 6275. sialylated oligosaccharide released from strain 6275 lipooligosaccharide by mild hydrolysis was determined to contain n-acetylneuraminic acid linked alpha 2-->3 to terminal galactose as shown below. [formula: see text] | 1993 | 8331087 |
| antibody responses to the capsular polysaccharide of neisseria meningitidis serogroup b in patients with meningococcal disease. | we measured antibody responses to meningococcal serogroup b (menb) polysaccharide (ps) by enzyme-linked immunosorbent assay (elisa) in sera from 94 patients from the netherlands with disease caused by neisseria meningitidis group b. the patients ranged in age from 3 to 73 years (mean age, 18.8 years). in initial studies we showed that the binding of a panel of menb ps-reactive human immunoglobulin m (igm) paraproteins to biotinylated menb ps bound to avidin-coated microtiter wells was inhibited ... | 1995 | 8548537 |
| inner core biosynthesis of lipooligosaccharide (los) in neisseria meningitidis serogroup b: identification and role in los assembly of the alpha1,2 n-acetylglucosamine transferase (rfak). | a lipooligosaccharide (los) mutant of neisseria meningitidis serogroup b strain nmb (immunotype l3,7,9) was identified in a tn916 (tetm) mutant bank by loss of reactivity with monoclonal antibody 3f11, which recognizes the terminal galbeta1-->4glcnac epitope in the lacto-n-neotetraose moiety of the wild-type los structure. the mutant, designated 559, was found to express a truncated los of 3.0 kda. southern and pcr analyses demonstrated that there was a single intact tn916 insertion (class i) in ... | 1996 | 8631701 |
| molecular subtyping of neisseria meningitidis serogroup b: comparison of five methods. | 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 ... | 1996 | 8735100 |
| invasion of primary nasopharyngeal epithelial cells by neisseria meningitidis is controlled by phase variation of multiple surface antigens. | we have investigated bacterial factors required for the entry of neisseria meningitidis serogroup b into mucosal cells using a novel in vitro infection model of primary cultures of human nasopharyngeal epithelium. an invasive meningococcal phenotype was obtained after several cycles of selection for intracellular bacteria with gentamicin. invasive bacteria differed from those in the initial inoculum in that they lacked a capsule and pili, exhibited a nonsialylated low-molecular-weight type of li ... | 1996 | 8757826 |
| modulation of the biological activities of meningococcal endotoxins by association with outer membrane proteins is not inevitably linked to toxicity. | meningococcal sepsis results partly from overproduction of host cytokines after macrophages interact with endotoxin. to obtain less toxic and highly immunomodulatory meningococcal endotoxins for prophylactic purposes, we investigated the relationship between endotoxicity and immunomodulatory activity of several endotoxin preparations from neisseria meningitidis group b. using the d-galactosamine-sensitized mouse model to determine endotoxin lethality, we found that the toxicity of purified lipoo ... | 1997 | 9125592 |
| identification and characterization of a dna region involved in the export of capsular polysaccharide by actinobacillus pleuropneumoniae serotype 5a. | actinobacillus pleuropneumoniae synthesizes a serotype-specific capsular polysaccharide that acts as a protective barrier to phagocytosis and complement-mediated killing. to begin understanding the role of a. pleuropneumoniae capsule in virulence, we sought to identify the genes involved in capsular polysaccharide export and biosynthesis. a 5.3-kb xbai fragment of a. pleuropneumoniae serotype 5a j45 genomic dna that hybridized with dna probes specific for the haemophilus influenzae type b cap ex ... | 1997 | 9169799 |
| humoral immune responses to neisseria meningitidis in children. | an understanding of the nature of immunity to serogroup b meningococci in childhood is necessary in order to establish the reasons for poor responses to candidate vaccines in infancy. we sought to examine the nature of humoral immune responses following infection in relation to age. serum bactericidal activity was poor in children under 12 months of age despite recent infection with neisseria meningitidis. the highest levels of bactericidal activity were seen in children over 10 years of age. ho ... | 1999 | 10225907 |
| cellular immune responses to neisseria meningitidis in children. | there is an urgent need for effective vaccines against serogroup b neisseria meningitidis. current experimental vaccines based on the outer membrane proteins (omps) of this organism provide a measure of protection in older children but have been ineffective in infants. we postulated that the inability of omp vaccines to protect infants might be due to age-dependent defects in cellular immunity. we measured proliferation and in vitro production of gamma interferon (ifn-gamma), tumor necrosis fact ... | 1999 | 10225908 |
| meningococcal disease and healthcare workers. | | 1999 | 10541486 |
| mannose-binding lectin binds to a range of clinically relevant microorganisms and promotes complement deposition. | mannose-binding lectin (mbl) is a collagenous serum lectin believed to be of importance in innate immunity. genetically determined low levels of the protein are known to predispose to infections. in this study the binding of purified mbl to pathogens isolated from immunocompromised children was investigated by flow cytometry. diverse candida species, aspergillus fumigatus, staphylococcus aureus, and beta-hemolytic group a streptococci exhibited strong binding of mbl, whereas escherichia coli, kl ... | 2000 | 10639434 |
| elevated levels of maternal anti-tetanus toxin antibodies do not suppress the immune response to a haemophilus influenzae type b polyribosylphosphate-tetanus toxoid conjugate vaccine. | reported are the effects of elevated levels of anti-tetanus antibodies on the safety and immune response to a haemophilus influenzae type b polyribosylphosphate (prp)-tetanus toxoid conjugate (prp-t) vaccine. a group of thai infants (n = 177) born to women immunized against tetanus during pregnancy were vaccinated with either a combined diphtheria-tetanus-pertussis (dtp) prp-t vaccine or dtp and a prp-conjugate vaccine using neisseria meningitidis group b outer-membrane proteins as a carrier (pe ... | 2000 | 10812736 |
| nmesi restriction-modification system identified by representational difference analysis of a hypervirulent neisseria meningitidis strain. | neisseria meningitidis is a gram-negative bacterium that may cause meningitis, sepsis, or both. the increase in the incidence of meningococcal disease in various countries in the past 2 decades is mainly due the genotypically related lineage iii meningococci. the chromosomal dna differences between lineage iii strains and non-lineage iii strains were identified using representational difference analysis. thus, a 1.8-kb locus that is specific for lineage iii meningococci was identified. the locus ... | 2001 | 11179359 |
| monoclonal antibodies specific for neisseria meningitidis group b polysaccharide and their peptide mimotopes. | from five mice immunized with escherichia coli k1 bacteria, we produced 12 immunoglobulin m hybridomas secreting monoclonal antibodies (mabs) that bind to neisseria meningitidis group b (nmgb). the 12 mabs also bound the capsular polysaccharide (ps) of e. coli k1 [which, like nmgb, is alpha(2-8)-linked polysialic acid (psa)] and bound to ev36, a nonpathogenic e. coli k-12 strain producing alpha(2-8) psa. except for hmenb5, which cross-reacted with n. meningitidis group c, none of the mabs bound ... | 2001 | 11292756 |
| come, a competence protein from neisseria gonorrhoeae with dna-binding activity. | neisseria gonorrhoeae is naturally able to take up exogenous dna and undergo genetic transformation. this ability correlates with the presence of functional type iv pili, and uptake of dna is dependent on the presence of a specific 10-bp sequence. among the known competence factors in n. gonorrhoeae, none has been shown to interact with the incoming dna. here we describe come, a dna-binding protein involved in neisserial competence. the gene come was identified through similarity searches in the ... | 2001 | 11325945 |
| activity and cross-reactivity of antibodies induced in mice by immunization with a group b meningococcal conjugate. | the capsular polysaccharide of group b neisseria meningitidis is composed of a linear homopolymer of alpha(2-8) n-acetyl neuraminic acid or polysialic acid (psa) that is also carried by isoforms of the mammalian neural cell adhesion molecule (ncam), which is especially expressed on brain cells during development. here we analyzed the ability of antibodies induced by the candidate vaccine n-propionyl polysaccharide tetanus toxoid conjugate to recognize psa-ncam. we hyperimmunized mice to produce ... | 2001 | 11598089 |
| transcriptome analysis of neisseria meningitidis during infection. | neisseria meningitidis is the cause of septicemia and meningococcal meningitis. during the course of infection, n. meningitidis encounters multiple environments within its host, which makes rapid adaptation to environmental changes a crucial factor for neisserial pathogenicity. employing oligonucleotide-based dna microarrays, we analyzed the transcriptome of n. meningitidis during two key steps of meningococcal infection, i.e., the interaction with epithelial cells (hela cells) and endothelial c ... | 2003 | 12486052 |
| management of diagnostic uncertainty in children with possible meningitis: a qualitative study. | neisseria meningitidis serogroup b is the most common cause of bacterial meningitis in children and young adults. early recognition and prompt intervention with antibiotics are thought to be key to preventing serious complications. | 2003 | 14601339 |
| diversity in coding tandem repeats in related neisseria spp. | tandem repeats contained within coding regions can mediate phase variation when the repeated units change the reading frame of the coding sequence in a copy number dependent manner. coding tandem repeats are those which do not alter the reading frame with copy number, and the changes in copy number of these repeats may then potentially alter the function or antigenicity of the protein encoded. three complete neisserial genomes were analyzed and compared to identify coding tandem repeats where th ... | 2003 | 14611665 |
| microarray genomotyping of key experimental strains of neisseria gonorrhoeae reveals gene complement diversity and five new neisserial genes associated with minimal mobile elements. | there are four widely used experimental strains of n. gonorrhoeae, one of which has been sequenced and used as the basis for the construction of a multi-strain, mutli-species pan-neisserial microarray. although the n. gonorrhoeae population structure is thought to be less diverse than n. meningitidis, there are some recognized gene-complement differences between strains, including the 59 genes of the gonococcal genetic island. in this study we have investigated the three experimental strains tha ... | 2004 | 15084227 |
| a gonococcal homologue of meningococcal gamma-glutamyl transpeptidase gene is a new type of bacterial pseudogene that is transcriptionally active but phenotypically silent. | it has been speculated that the gamma-glutamyl transpeptidase (ggt) gene is present only in neisseria meningitidis and not among related species such as neisseria gonorrhoeae and neisseria lactamica, because n. meningitidis is the only bacterium with ggt activity. however, nucleotide sequences highly homologous to the meningococcal ggt gene were found in the genomes of n. gonorrhoeae isolates. | 2005 | 16202144 |
| toward a genome-wide systems biology analysis of host-pathogen interactions in group a streptococcus. | genome-wide analysis of microbial pathogens and molecular pathogenesis processes has become an area of considerable activity in the last 5 years. these studies have been made possible by several advances, including completion of the human genome sequence, publication of genome sequences for many human pathogens, development of microarray technology and high-throughput proteomics, and maturation of bioinformatics. despite these advances, relatively little effort has been expended in the bacterial ... | 2005 | 16314461 |
| variations in gene organization and dna uptake signal sequence in the folp region between commensal and pathogenic neisseria species. | horizontal gene transfer is an important source of genetic variation among neisseria species and has contributed to the spread of resistance to penicillin and sulfonamide drugs in the pathogen neisseria meningitidis. sulfonamide resistance in neisseria meningitidis is mediated by altered chromosomal folp genes. at least some folp alleles conferring resistance have been horizontally acquired from other species, presumably from commensal neisseriae. in this work, the dna sequence surrounding folp ... | 2006 | 16503987 |
| microsatellite polymorphism across the m. tuberculosis and m. bovis genomes: implications on genome evolution and plasticity. | microsatellites are the tandem repeats of nucleotide motifs of size 1-6 bp observed in all known genomes. these repeats show length polymorphism characterized by either insertion or deletion (indels) of the repeat units, which in and around the coding regions affect transcription and translation of genes. | 2006 | 16603092 |
| the majority of genes in the pathogenic neisseria species are present in non-pathogenic neisseria lactamica, including those designated as 'virulence genes'. | neisseria meningitidis causes the life-threatening diseases meningococcal meningitis and meningococcal septicemia. neisseria gonorrhoeae is closely related to the meningococcus, but is the cause of the very different infection, gonorrhea. a number of genes have been implicated in the virulence of these related yet distinct pathogens, but the genes that define and differentiate the species and their behaviours have not been established. further, a related species, neisseria lactamica is not assoc ... | 2006 | 16734888 |
| expression of innate immune complement regulators on brain epithelial cells during human bacterial meningitis. | in meningitis, the cerebrospinal fluid contains high levels of innate immune molecules (e.g. complement) which are essential to ward off the infectious challenge and to promote the infiltration of phagocytes (neutrophils, monocytes). however, epithelial cells of either the ependymal layer, one of the established niche for adult neural stem cells, or of the choroid plexus may be extremely vulnerable to bystander attack by cytotoxic and cytolytic complement components. | 2006 | 16948860 |
| a fast real-time polymerase chain reaction method for sensitive and specific detection of the neisseria gonorrhoeae pora pseudogene. | ever since the advent of molecular methods, the diagnostics of neisseria gonorrhoeae has been troubled by false negative and false positive results compared with culture. commensal neisseria species and neisseria meningitidis are closely related to n. gonorrhoeae and may cross-react when using molecular tests comprising too-low specificity. we have devised a real-time polymerase chain reaction (pcr), including an internal amplification control, that targets the n. gonorrhoeae pora pseudogene. dn ... | 2006 | 17065426 |
| polymorphisms in the mannose binding lectin-2 gene and acute respiratory distress syndrome. | the variant alleles in the mannose binding lectin-2 (mbl-2) gene have been associated with mbl deficiency and increased susceptibility to sepsis. we postulate that the variant mbl-2 genotypes are associated with increased susceptibility to and mortality in acute respiratory distress syndrome (ards). | 2007 | 17133182 |
| transcriptional profiling of actinobacillus pleuropneumoniae under iron-restricted conditions. | to better understand effects of iron restriction on actinobacillus pleuropneumoniae and to identify new potential vaccine targets, we conducted transcript profiling studies using a dna microarray containing all 2025 orfs of the genome of a. pleuropneumoniae serotype 5b strain l20. this is the first study involving the use of microarray technology to monitor the transcriptome of a. pleuropneumoniae grown under iron restriction. | 2007 | 17355629 |
| the capsule polysaccharide structure and biogenesis for non-o1 vibrio cholerae nrt36s: genes are embedded in the lps region. | in v. cholerae, the biogenesis of capsule polysaccharide is poorly understood. the elucidation of capsule structure and biogenesis is critical to understanding the evolution of surface polysaccharide and the internal relationship between the capsule and lps in this species. v. cholerae serogroup o31 nrt36s, a human pathogen that produces a heat-stable enterotoxin (nag-st), is encapsulated. here, we report the covalent structure and studies of the biogenesis of the capsule in v. cholerae nrt36s. | 2007 | 17362509 |
| burn injury reveals altered phenotype in mannan-binding lectin-deficient mice. | burn injury destroys skin, the second largest innate immune organ in the body, and triggers chaotic immune and inflammatory responses. the pattern recognition molecule, mannan-binding lectin (mbl), plays an important role in the first-line host defense against infectious agents. mbl initiates the lectin complement pathway and acts as an opsonin. recent studies suggest that mbl also modulates inflammatory responses. we report that local responses after burn in mbl null mice differ from those foun ... | 2007 | 17363917 |
| tlr4-dependent adjuvant activity of neisseria meningitidis lipid a. | the adjuvant activity of neisseria meningitidis serogroup b lipopoly(oligo)saccharide (los) from wild-type and genetically defined los mutants and unglycosylated meningococcal lipid a was assessed in c3h/hen and c3h/hej mice. meningococcal lipid a, a weak agonist for tlr4/md-2 in human macrophages, was found to have adjuvant activity similar to that of wild-type and kdo(2)-lipid a los in c3h/hen mice. all meningococcal los structures as adjuvants induced high titers of igg1, igg2a and igg2b but ... | 2007 | 17466419 |
| pathogen proteins eliciting antibodies do not share epitopes with host proteins: a bioinformatics approach. | the best way to prevent diseases caused by pathogens is by the use of vaccines. the advent of genomics enables genome-wide searches of new vaccine candidates, called reverse vaccinology. the most common strategy to apply reverse vaccinology is by designing subunit recombinant vaccines, which usually generate an humoral immune response due to b-cell epitopes in proteins. a major problem for this strategy is the identification of protective immunogenic proteins from the surfome of the pathogen. ep ... | 2007 | 17551592 |
| phagocytosis and intracellular killing of md-2 opsonized gram-negative bacteria depend on tlr4 signaling. | both toll-like receptor 4 (tlr4)- and md-2-deficient mice succumb to otherwise nonfatal gram-negative bacteria inocula, demonstrating the pivotal role played by these proteins in antibacterial defense in mammals. md-2 is a soluble endogenous ligand for tlr4 and a receptor for lipopolysaccharide (lps). lps-bound md-2 transmits an activating signal onto tlr4. in this report, we show that both recombinant and endogenous soluble md-2 bind tightly to the surface of live gram-negative bacteria. as a c ... | 2008 | 18203953 |
| triad pattern algorithm for predicting strong promoter candidates in bacterial genomes. | bacterial promoters, which increase the efficiency of gene expression, differ from other promoters by several characteristics. this difference, not yet widely exploited in bioinformatics, looks promising for the development of relevant computational tools to search for strong promoters in bacterial genomes. | 2008 | 18471287 |
| a role for mannose-binding lectin, a component of the innate immune system in pre-eclampsia. | mannose-binding lectin (mbl) is a pattern-recognition receptor that activates complement and modulates inflammation. homozygosity for the most common allele of the mbl2 gene that is associated with high mbl serum concentrations is more prevalent among patients with pre-eclampsia. the objective of this study was to determine maternal plasma mbl concentrations in normal pregnant women and patients with pre-eclampsia. | 2008 | 18727690 |
| snapshot of iron response in shewanella oneidensis by gene network reconstruction. | iron homeostasis of shewanella oneidensis, a gamma-proteobacterium possessing high iron content, is regulated by a global transcription factor fur. however, knowledge is incomplete about other biological pathways that respond to changes in iron concentration, as well as details of the responses. in this work, we integrate physiological, transcriptomics and genetic approaches to delineate the iron response of s. oneidensis. | 2009 | 19321007 |
| vaccines containing de-n-acetyl sialic acid elicit antibodies protective against neisseria meningitidis groups b and c. | murine mabs that were produced by immunization with a vaccine containing the n-propionyl derivative of neisseria meningitidis group b (menb) capsular polysaccharide (npr mbps) mediate protective responses against menb but were not reactive with unmodified mbps or chemically identical human polysialic acid (psa). recently, we showed that some of the mabs were reactive with mbps derivatives that contain de-n-acetyl sialic acid residues. in this study we evaluated the immunogenicity of de-n-acetyl ... | 2009 | 19414816 |
| intradermal immunization improves protective efficacy of a novel tb vaccine candidate. | we have developed the mycobacterium tuberculosis (mtb) fusion protein (id83), which contains the three mtb proteins rv1813, rv3620 and rv2608. we evaluated the immunogenicity and protective efficacy of id83 in combination with several emulsion-formulated toll-like receptor agonists. the id83 subunit vaccines containing synthetic tlr4 or tlr9 agonists generated a t helper-1 immune response and protected mice against challenge with mtb regardless of route. the id83 vaccine formulated with gardiqui ... | 2009 | 19428920 |
| sensitivity of erythrocyte sedimentation rate and c-reactive protein in childhood bone and joint infections. | in addition to the examination of clinical signs, several laboratory markers have been measured for diagnostics and monitoring of pediatric septic bone and joint infections. traditionally erythrocyte sedimentation rate (esr) and leukocyte cell count have been used, whereas c-reactive protein (crp) has gained in popularity. we monitored 265 children at ages 3 months to 15 years with culture-positive osteoarticular infections with a predetermined series of esr, crp, and leukocyte count measurement ... | 2010 | 19533263 |
| sensitivity of erythrocyte sedimentation rate and c-reactive protein in childhood bone and joint infections. | in addition to the examination of clinical signs, several laboratory markers have been measured for diagnostics and monitoring of pediatric septic bone and joint infections. traditionally erythrocyte sedimentation rate (esr) and leukocyte cell count have been used, whereas c-reactive protein (crp) has gained in popularity. we monitored 265 children at ages 3 months to 15 years with culture-positive osteoarticular infections with a predetermined series of esr, crp, and leukocyte count measurement ... | 2010 | 19533263 |
| developmental biology of the innate immune response: implications for neonatal and infant vaccine development. | molecular characterization of mechanisms by which human pattern recognition receptors (prrs) detect danger signals has greatly expanded our understanding of the innate immune system. prrs include toll-like receptors, nucleotide oligomerization domain-like receptors, retinoic acid inducible gene-like receptors, and c-type lectin receptors. characterization of the developmental expression of these systems in the fetus, newborn, and infant is incomplete but has yielded important insights into neona ... | 2009 | 19918215 |
| effect of human serum on de-n-acetyl sialic acid epitope expression and antibody activity against n. meningitidis group b. | antibody-mediated complement-dependent bactericidal activity (bca) against neisseria meningitidis (nm) is correlated with protection against invasive disease. recently, we showed that murine antibodies elicited by neuraminic acid-containing polysialic acid (neupsa) antigens conferred protection against nm group b (nmb) strains in an infant rat model of meningococcal bacteremia [moe gr, bhandari ts, flitter ba. vaccines containing de-n-acetyl sialic acid elicit antibodies protective against neiss ... | 2010 | 20637761 |
| genome-wide gene order distances support clustering the gram-positive bacteria. | initially using 143 genomes, we developed a method for calculating the pair-wise distance between prokaryotic genomes using a monte carlo method to estimate the conservation of gene order. the method was based on repeatedly selecting five or six non-adjacent random orthologs from each of two genomes and determining if the chosen orthologs were in the same order. the raw distances were then corrected for gene order convergence using an adaptation of the jukes-cantor model, as well as using the co ... | 2015 | 25653643 |
| genome-wide gene order distances support clustering the gram-positive bacteria. | initially using 143 genomes, we developed a method for calculating the pair-wise distance between prokaryotic genomes using a monte carlo method to estimate the conservation of gene order. the method was based on repeatedly selecting five or six non-adjacent random orthologs from each of two genomes and determining if the chosen orthologs were in the same order. the raw distances were then corrected for gene order convergence using an adaptation of the jukes-cantor model, as well as using the co ... | 2015 | 25653643 |
| clustering the annotation space of proteins. | current protein clustering methods rely on either sequence or functional similarities between proteins, thereby limiting inferences to one of these areas. | 2005 | 15703069 |
| meta-analysis of general bacterial subclades in whole-genome phylogenies using tree topology profiling. | in the last two decades, a large number of whole-genome phylogenies have been inferred to reconstruct the tree of life (tol). underlying data models range from gene or functionality content in species to phylogenetic gene family trees and multiple sequence alignments of concatenated protein sequences. diversity in data models together with the use of different tree reconstruction techniques, disruptive biological effects and the steadily increasing number of genomes have led to a huge diversity ... | 2012 | 22915837 |
| the bactericidal/permeability-increasing protein (bpi) in infection and inflammatory disease. | gram-negative bacteria (gnb) and their endotoxin present a constant environmental challenge. endotoxins can potently signal mobilization of host defenses against invading gnb but also potentially induce severe pathophysiology, necessitating controlled initiation and resolution of endotoxin-induced inflammation to maintain host integrity. the bactericidal/permeability-increasing protein (bpi) is a pluripotent protein expressed, in humans, mainly neutrophils. bpi exhibits strong antimicrobial acti ... | 2007 | 17678885 |
| bacterial etiologies of five core syndromes: laboratory-based syndromic surveillance conducted in guangxi, china. | under the existing national surveillance system in china for selected infectious diseases, bacterial cultures are performed for only a small percentage of reported cases. we set up a laboratory-based syndromic surveillance system to elucidate bacterial etiologic spectrum and detect infection by rare etiologies (or serogroups) for five core syndromes in the given study area. | 2014 | 25360596 |
| fatal meningococcemia. | within the past six years, a case of bothwaterhouse-freidrichsen syndrome and fulminant meningococcemia have presented to union memorial hospital. both cases presented in markedly different fashions, differed in microbiologic serogrouping, showed minimal histopathologic similarities; however achieved ultimately the same outcome through two different pathological pathways. the following case reports illustrate two mechanisms through which n. meningitis may pathogenize a host, both leading to comp ... | 2011 | 23882342 |
| fatal meningococcemia. | within the past six years, a case of bothwaterhouse-freidrichsen syndrome and fulminant meningococcemia have presented to union memorial hospital. both cases presented in markedly different fashions, differed in microbiologic serogrouping, showed minimal histopathologic similarities; however achieved ultimately the same outcome through two different pathological pathways. the following case reports illustrate two mechanisms through which n. meningitis may pathogenize a host, both leading to comp ... | 2011 | 23882342 |
| vaccines against drug abuse. | the currently available medications for the treatment of drug abuse have had only limited success. anti-addiction vaccines, aimed at eliciting antibodies that block the pharmacological effects of drugs, have great potential for treating drug abuse. we review the status of two vaccines that are undergoing clinical trials (for cocaine and nicotine addiction) and two that are still in preclinical development (for methamphetamine and heroin addiction). we also outline the challenges and ethical conc ... | 2011 | 22130115 |
| vaccines against drug abuse. | the currently available medications for the treatment of drug abuse have had only limited success. anti-addiction vaccines, aimed at eliciting antibodies that block the pharmacological effects of drugs, have great potential for treating drug abuse. we review the status of two vaccines that are undergoing clinical trials (for cocaine and nicotine addiction) and two that are still in preclinical development (for methamphetamine and heroin addiction). we also outline the challenges and ethical conc ... | 2011 | 22130115 |
| fh-dependent complement evasion by disease-causing meningococcal strains with absent fhbp genes or frameshift mutations. | meningococci bind human fh to down-regulate complement, which enhances survival of the bacteria in serum. a major fh ligand is the vaccine candidate, factor h-binding protein (fhbp). although fhbp has been considered an essential meningococcal virulence factor, rarely, invasive isolates with absent fhbp genes or frameshift mutations have been identified. in previous studies fh binding to these isolates was not detected. the aim of the present study was to investigate fh binding and complement ev ... | 2013 | 23791680 |
| the solute carrier family 10 (slc10): beyond bile acid transport. | the solute carrier (slc) family 10 (slc10) comprises influx transporters of bile acids, steroidal hormones, various drugs, and several other substrates. because the seminal transporters of this family, namely, sodium/taurocholate cotransporting polypeptide (ntcp; slc10a1) and the apical sodium-dependent bile acid transporter (asbt; slc10a2), were primarily bile acid transporters, the term "sodium bile salt cotransporting family" was used for the slc10 family. however, this notion became obsolete ... | 2013 | 23506869 |
| prevalence and detection of stenotrophomonas maltophilia carrying metallo-β-lactamase blal1 in beijing, china. | intrinsic β-lactam resistance in stenotrophomonas maltophilia is caused by bla l1 and/or bla l2, a kind of metallo-β-lactamase with a broad substrate spectrum including carbapenems. a rapid and sensitive molecular method for the detection of bla l1 in clinical samples is needed to guide therapeutic treatment. in present study, we first described a loop-mediated isothermal amplification (lamp) method for the rapid detection of bla l1 in clinical samples by using two methods including a chromogeni ... | 2014 | 25538701 |
| epidemiological characteristics of meningococcal meningitis in the area of zenica-doboj canton in period from 2008 to 2012. | meningococcal meningitis now represents a significant public health problem, not only in developing countries but also in developed ones. the disease usually occurs sporadically, and much less in smaller epidemics. | 2014 | 25568534 |
| meningococcal serogroup b vaccine in italy: state-of-art, organizational aspects and perspectives. | neisseria meningitidis causes severe invasive meningococcal diseases (imds) in humans including meningitis and septicemia, responsible for serious clinical conditions and leading to life-long disabilities and death. serogroup b dominates imds burden in italy, accounting for over 60% of total cases. on january 2013 the european medicine agency (ema) licensed the first serogroup b meningococcal (menb) vaccine in europe. a number of european countries and regions have introduced the new menb vaccin ... | 2015 | 26788733 |
| monoclonal antibody combinations that present synergistic neutralizing activity: a platform for next-generation anti-toxin drugs. | monoclonal antibodies (mabs) are among the fastest-growing therapeutics and are being developed for a broad range of indications, including the neutralization of toxins, bacteria and viruses. nevertheless, mabs potency is still relatively low when compared to conventional polyclonal ab preparations. moreover, the efficacy of an individual neutralizing mab may significantly be hampered by the potential absence or modification of its target epitope in a mutant or subtype of the infectious agent. t ... | 2015 | 26035486 |
| asymmetric and unilateral hearing loss in children. | asymmetric and unilateral hearing losses in children have traditionally been underappreciated, but health care practitioners are now beginning to understand their effect on development and the underlying pathophysiologic mechanisms. the common wisdom among medical and educational professionals has been that at least one normal-hearing or near-normal-hearing ear was sufficient for typical speech and language development in children. the objective of this review is to illustrate, to the non-otolar ... | 2015 | 26004144 |