Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0348321 (Haemophilus)
 15,372 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

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 IgG subclass antibodies and with IgG1 and IgG3 anti-Rhesus D, and the activities of CD32 with IgG1 and IgG3 anti-Rhesus D. With respect to the allotypes of CD16, polymorphonuclear leucocytes (PMN) homozygous for Fc gamma RIIb-NA2 exhibited a lower (21-25%) IgG1-mediated phagocytosis of Staphylococcus aureus strain Wood (STAW), Haemophilus influenzae type b (Hib), and Neisseria meningitidis group B (NMen) than IIIb-NA1 PMN. The difference was apparent only when the micro-organisms were opsonized in the absence of complement, and was furthermore enhanced (34-52%) upon blockade of Fc gamma RIIa. In addition, monoclonal IgG3 anti-D-mediated rosette formation and phagocytosis was consistently found to be lower (16%) with Fc gamma RIIIb-NA2 than with IIIb-NA1 PMN. For the allotypes of CD32 we now show that IgG3 anti-D sensitized erythrocytes formed more (50%) rosettes and were phagocytosed at a higher rate with PMN carrying Fc gamma RIIa-H131 than with PMN carrying IIa-R131. Heterozygous Fc gamma RIIa-H/R131 PMN exhibited intermediate phagocytic activity in this respect. This study illustrates a critical role of Fc gamma R allotypes in functional interactions with biologically relevant IgG subclass antibodies.
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PMID: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. 787 42

The purpose of our experiment is to examine the level of anti-Haemophilus influenza polysaccharide antibody titer in the Korean population. Using ELISA, the level of Hib-PS antibodies in 384 infants and children who were all free from Hib invasive diseases, was tested. And the blood of 50 mothers within 24 hours of delivery and cord blood from their respective full-term neonates was also tested. The transport of Hib-PS IgG and IgG subclasses in paired sera from mothers and neonates was also measured. The titer of Hib-PS IgG varies with age. At birth the mean optical density of cord blood was 1.028; however, it declined to 0.609 up to 6 months and further decline was noted up to 2 years to 0.488. Then the mean O.D. remained around 0.5 from 3 to 14 years of age. The mean O.D. of Hib-PS IgG in the mothers blood was 0.856. The ratio of mean O.D. of anti-Hib PS IgG antibody in the cord blood to that in the maternal blood was 1.20. The mean optical densities of IgG subclasses were: 1.18 for anti-Hib PS IgG1, 1.07 for anti-Hib PS IgG2, 1.01 for anti-Hib PS IgG3, and 1.09 for anti-Hib PS IgG4. The sera from Korean children of almost all age groups reacted to Hib-PS antigen on ELISA. Also the active transport of anti-Hib PS IgG antibody through placenta was observed. Among four IgG subclasses, only IgG1 transport had significant experimental meaning.
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PMID:Reaction of the sera of the Korean children free from Hib invasive diseases against H. influenzae type B capsular polysaccharide antigen. 806 14

The host-parasite relationship in the nasopharynx of young children with bacterial colonization and antigen uptake in the mucosa and lymphatic tissue provides an opportunity to investigate infectious/inflammatory processes and responses. IL-1 beta, IL-6 and tumour necrosis factor-alpha (TNF-alpha) were analysed in nasopharyngeal secretions and serum from children with or without recurrent episodes of acute otitis media, from healthy adults and adults with or without recurrent episodes of acute otitis media, from healthy adults and adults with hypogammaglobulinaemia or selective deficiency of IgG3. Nasopharyngeal secretions generally contained substantial amounts of IL-1 beta, IL-6 and TNF-alpha. In contrast, IL-1 beta, IL-6 and TNF-alpha were not detectable in sera on the same occasion. Children were found to have higher levels of IL-1 beta, IL-6 and TNF-alpha than healthy adults and than adults with immunodeficiency. High levels of IL-1 beta were associated with low or undetectable levels of IL-6 and TNF-alpha, whereas the opposite pattern was seen in association with low levels of IL-1 beta. This was especially true for children with recurrent episodes of acute otitis media (RAOM). In children with nasopharyngeal colonization with Haemophilus influenzae, significantly higher levels of IL-1 beta, IL-6 and TNF-alpha (P = 0.0001, respectively) were found compared with non-colonized children. Notably, the RAOM children exhibited significantly lower levels of IL-1 beta, IL-6, and TNF-alpha in nasopharyngeal secretions (P = 0.0001, 0.01 and 0.0001, respectively) than healthy children. These results demonstrate local production of inflammatory cytokines in nasopharynx, related to bacterial colonization, and suggest that children with RAOM are poor nasopharyngeal cytokine producers.
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PMID:Cytokines in nasopharyngeal secretions; evidence for defective IL-1 beta production in children with recurrent episodes of acute otitis media. 808 94

Antibodies directed to capsular polysaccharides form an essential component in the defence against infections with encapsulated bacteria such as Streptococcus pneumoniae and Haemophilus influenzae type b. Immune responses to polysaccharide antigens can occur in the absence of a functional thymus and the antigens are therefore designated as thymus independent. However, regulatory T cells may influence the magnitude of the antibody response to capsular polysaccharide antigens. So-called thymus independent type 2 antigens share several features of their immune response such as late development of antibody synthesis in ontogeny, no memory formation and a restricted isotype (IgM, IgG2) and idiotype usage. In infants and young children up to the age of 2 years the antibody response to capsular polysaccharides is inadequate resulting in an increased incidence of diseases such as pneumonia, meningitis, otitis and other forms of bacteremic disease. Anti-capsular polysaccharide antibody deficiency does occur in a number of well defined immunodeficiency syndromes including hypo- or agammaglobulinaemia, selective IgA and/or IgG subclass deficiency, Wiskott-Aldrich syndrome, DiGeorge anomaly and also in acquired immune deficiencies such as AIDS, and some forms of lymphoid malignancies. In elderly and in conditions such as splenectomy an increased incidence of infections with encapsulated bacteria does occur, sometimes but not always on basis of a defect in antibody formation. Clinicians are often confronted with young patients older than 2 years of age suffering from recurrent severe bacterial infections of the respiratory tract. In these patients no overt immunodeficiency is demonstrable but recent results indicated that a small percentage may show a selective defect in the antibody response since upon vaccination with polysaccharide vaccines no increase in antibody titer does occur. Though antibodies to polysaccharide antigens in young children are mainly of the IgM and IgG1 (IgG3) isotype, in older children and adults the polysaccharide antibodies are predominantly localized in the IgG2 subclass. The bridge between IgG2 type antibodies and phagocytosis of encapsulated bacteria is constituted by Fc gamma receptors for IgG2 on effector cells. The recent finding that allotypes of Fc gamma RIIa do exist that either bind or do not bind IgG2 type antibodies strongly suggests that the defence of a given individual to encapsulated bacteria apart from an intact antibody formation and the complement system also is determined by the allotype of the appropriate Fc gamma receptor.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Anti-capsular polysaccharide antibody deficiency states. 816 45

Structural analysis of the human immunoglobulin repertoire holds promise for determining the basis of variable region gene usage in response to a variety of auto and exogenous antigens. Here we report the nucleotide sequences of the heavy and light chain variable regions expressed by three human monoclonal antibodies specific for two clinically relevant bacterial pathogens, Bordetella pertussis and Haemophilus influenzae type b. The cell lines were derived by in vitro stimulation of lymphocytes from spleen or tonsillar tissue, respectively, and bind to different antigens from the two organisms. The single B. pertussis antibody is of the IgM lambda isotype and utilizes the single VH6 gene segment in combination with a V lambda 2 gene and demonstrates limited somatic mutation, yet is highly indicative of an antigen-driven immune response. One H. influenzae antibody is of the IgG2 lambda isotype and expresses a VH3 gene segment with a V lambda 1 gene, while the second cell line produces an IgG3 lambda antibody expressing a combination of VH2/V lambda 3. Both molecules show evidence of somatic mutation. The D gene segments of the heavy chains vary in length and display limited sequence homology with known germline D segments. As demonstrated previously, JH4 predominates (two JH4 and one JH3) and all three utilize the J lambda 3 gene segment. In addition, we have isolated and sequenced a number of germline VH2 gene segments in an attempt to better understand the nature of the VH2 germline repertoire. In addition to contributing to the understanding of the human antibody repertoire, such clinically relevant molecules may prove to be a source of passive immunotherapy for those at risk to developing disease.
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PMID:Molecular characterization of human antibodies to bacterial antigens: utilization of the less frequently expressed VH2 and VH6 heavy chain variable region gene families. 824 31

Four murine monoclonal antibodies (MAbs) reactive with the outer-core region of the lipopolysaccharide (LPS) from Haemophilus influenzae were generated after immunization with azide-killed H. influenzae RM.7004 AH1-2 and their epitope specificities studied. The monoclonal antibodies: MAHI 6 (IgM), MAHI 5 (IgG2a), MAHI 8 (IgG3), and MAHI 11 (IgG2b) bound to synthetic glycoconjugates or glycolipids with terminal galabiosyl (Gal alpha 1-->4Gal beta 1-) or globotriaosyl (Gal alpha 1-->4Gal beta 1 1-->4GLc) residues as evaluated in enzyme immunoassays (EIA). Glycoconjugates or glycolipids with internally placed galabiose elements were not active, indicating selectively of the MAbs for recognition of the epitope. Nine LPSs from H. influenzae inhibited the binding of the four MAbs. The presence of the galabiosyl disaccharide element in these nine LPSs was evidence by the binding of 125I-labeled Shiga toxin isolated from the bacterium Shigella dysenteriae type 1, reported to have as receptor the Gal alpha 1-->4Gal beta disaccharide (Lindberg et al., J Biol Chem, 1987, 262: 1779-85). Structural studies of these H. influenzae LPSs were also in accord with the presence of the galabiosyl disaccharide, in addition 1H-NMR spectroscopy showed the presence of O-acetyl groups in the RM.7004 AH1-2 LPS. However, differential binding specificities of the MAbs to modified RM.7004 AH1-2 LPSs were observed. MAHI 6 and MAHI 11 bound equally well to LPS, polysaccharides obtained after mild acidic treatment, and dephosphorylated LPS samples as shown in inhibition EIA. In contrast, both dephosphorylated LPS samples and polysaccharides were poorer inhibitors of the binding of MAHI 5 and MAHI 8 to native RM.7004 AH1-2 LPS. Neither the de-O-acylated nor the de-O,N-acylated LPSs were effective inhibitors of any of the four MAbs. These results suggest that the MAbs recognition involves Gal alpha 1-->4Gal and O-acetyl and other saccharide residue(s) from the oligosaccharide moiety of the LPS. The epitopes are also expressed and accessible to recognition in clinical isolates coming from different sources of Neisseria spp., Haemophilus spp., and Moraxella catarrhalis, but not in Bordetella spp., Aeromonas spp. or Enterobacteriaceae as evaluated by whole-bacteria EIA and colony-dot-immunoblotting.
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PMID:Binding specificity for four monoclonal antibodies recognizing terminal Gal alpha 1-->4Gal residues in Haemophilus influenzae lipopolysaccharide. 855 43

Only a small number of patients with IgG subclass deficiencies (IgGSD) have been observed to have bronchiectasis. Moreover, in the series of patients with bronchiectasis, IgGSD have not been found at any frequency, and the etiology of bronchiectasis remains unclear in 29 to 49% of cases. Serum concentrations of total IgG, IgA, and IgG subclasses as well as pulmonary function were measured in 65 patients (aged: 10 to 74 yr) with bronchiectasis of unknown etiology. An ELISA test was performed to quantify subclasses 1 through 4 using subclass-specific antihuman monoclonal antibodies. IgG subclass estimation in a healthy population with age-stratified normal ranges was derived from 100 adults, 37 children aged between 10 and 12 yr, and 27 adolescents aged between 13 and 16 yr. Serum concentrations of specific IgG antibodies to Haemophilus influenzae type b capsular polysaccharide (Hib-PRP) were also assayed by an ELISA test in 19 of the patients (10 with IgGSD and nine with non-IgGSD) and in 58 healthy individuals before and 3 wk after immunization with Hib-PRP conjugated to meningococcal outer membrane protein complex (OMPC). Thirty-one patients (48%) had low serum concentrations of one or more IgG subclasses (19 IgG2 deficiencies, 2 IgG3 deficiencies, 3 IgG4 deficiencies, and 7 combined subclass deficiencies). All patients showed increased levels of total IgG, IgG1, and IgA, but this rise was significantly higher in patients without IgGSD. Patients with IgGSD showed impaired antibody response to Hib-PRP compared with patients with non-IgGSD and the control group. IgGSD, particularly IgG2 deficiency, are not an unusual cause of bronchiectasis. Therefore, serum levels of IgG subclasses must be assayed whenever other causes of bronchiectasis have been ruled out.
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PMID:IgG subclass deficiencies associated with bronchiectasis. 856 13

A total of 117 consecutive patients with primary antibody deficiencies were followed for up to 5 years with regard to acute respiratory tract infections. Nontypeable Haemophilus influenzae (NTHI) was the sole pathogen in 61% (202/330) of the samples from which a potential pathogen was recovered. Common variable immunodeficiency (CVI) was the most prevalent condition (27/39 patients) in the group where H. influenzae was isolated. In patients where H. influenzae was not found only 9/78 patients had CVI. 49 of these 78 patients had isolated IgG3 or IgA deficiency. Both of these entities seemed to be associated with a lower prevalence of NTHI infections. 13 of 18 patients with at least 2 isolates of NTHI were colonized with the same strain from 3 to 43 months as shown by total genomic DNA-fingerprinting. Recurrent symptomatic infections occurred in these patients despite substitution therapy with gammaglobulins and repeated antibiotic treatments. All but 2 of the 224 H. influenzae isolates were beta-lactamase negative and sensitive to ampicillin. The use of 10 lipopolysaccharide-specific monoclonal antibodies in a whole cell ELISA showed that the LPS-epitopes on the 224 H. influenzae isolates from the hypogammaglobulinemic group were very similar to 499 NTHI isolates from immunocompetent patients with respiratory infections. One may therefore conclude that i) patients with CVI, were prone to be permanently colonized with NTHI, and ii) the colonizing bacteria were ordinary strains showing the same LPS-phenotypes as those strains that cause acute respiratory tract infections in immunocompetent individuals.
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PMID:Characterization of Haemophilus influenzae isolates from the respiratory tract of patients with primary antibody deficiencies: evidence for persistent colonizations. 865 61

Seven murine monoclonal antibodies (mAbs) against serotype 1 of Actinobacillus (Haemophilus) pleuropneumoniae (reference strain Shope 4074) were produced and characterized. All hybridomas secreting mAbs were reactive with whole-cell antigens from reference strains of serotypes 1, 9 and 11, except for mAb 5D6 that failed to recognized serotype 9. They did not react with other taxonomically related Gram-negative organisms tested. The predominant isotype was immunoglobulin (Ig) M, although IgG2a, IgG2b, and IgG3 were also obtained. The epitopes identified by these mAbs were resistant to proteinase K treatment and boiling in the presence of sodium dodecyl sulfate and reducing conditions; however, they were sensitive to sodium periodate treatment. Enhanced chemiluminescence-immunodetection assay showed that mAbs could be divided in two groups according to the patterns of immunoreaction observed. Group 1 (mAbs 3E10, 4B7, 9H5 and 11C3) recognized a ladder-like banding profile consistent with the O antigen of lipopolysaccharide (LPS) from smooth strains. Group II (mAbs 3B10 and 9H1) recognized a long smear of high molecular weight which ranged from 60 to 200 kDa. The mAbs were tested against 96 field isolates belonging to serotypes 1, 5, 9, 11 and 12, which had previously been classified by a combination of serological techniques based on polyclonal rabbit sera (counterimmunoelectrophoresis, immunodiffusion and coagglutination). The panel of mAbs identified all isolates of serotypes 9 and 11, but only 66% of those belonging to serotype 1. This may suggest the existence of antigenic heterogeneity among isolates of A. pleuropneumoniae serotype 1. These mAbs reacted with epitopes common to serotypes 1, 9 and 11 of Actinobacillus pleuropneumoniae which were located on the O antigen of LPS.
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PMID:Characterization of monoclonal antibodies that recognize common epitopes located on O antigen of lipopolysaccharide of serotypes 1, 9 and 11 of Actinobacillus pleuropneumoniae. 911 34

Children with acute otitis media as the result of nontypable Haemophilus influenzae often develop serum bactericidal and/or opsonic IgG antibodies to this organism during convalescence. Outer membrane proteins appear to be the principal targets for such antibodies. In this study we characterized the IgG subclass responses to major outer membrane proteins of nontypable H. influenzae in otitis-prone children in whom this organism had colonized. Three of the major outer membrane proteins (P2, P5, and P6) were isolated from the homologous nontypable H. influenzae strain recovered from the middle ear at the time of acute infection. Sera were obtained during the acute phase and at 1 and 6 months thereafter. The outer membrane proteins, which were isolated by preparative sodium dodecylsulfate-polyacrylamide gel electrophoresis, were used as test antigens in a quantitative IgG subclass enzyme immunoassay. The results of this analysis indicate that the temporal characteristics and distribution of IgG subclass antibodies were found to differ for each of the outer membrane proteins. Moreover, substantial variation between patients was observed with respect to both temporal characteristics and subclass distribution of the IgG response to the three outer membrane proteins. Significantly, sera from two of three otitis-prone subjects contained detectable levels of IgG antibody to the conserved P6 outer membrane protein at the time of acute infection, with serum from one subject also containing detectable levels of IgG3 antibody to this same protein. Nevertheless, the organism persisted in the middle ears of these patients. The results of this study indicate that otitis-prone children manifest a highly variable IgG subclass response to both conserved (P6) and variable (P2) outer membrane proteins of nontypable H. influenzae. Further study is required to ascertain whether these IgG subclass antibodies are biologically efficacious and whether otitis-prone children possess the immunologic maturity to respond to nontypable H. influenzae outer membrane protein-based vaccines in a predictable manner.
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PMID:Immunoglobulin G subclass response to major outer membrane proteins of nontypable Haemophilus influenzae in children with acute otitis media. 912 92


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