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)

Monoclonal IgA paraproteins of subclasses 1 and 2, isolated from the sera of myeloma patients, were incubated for 4, 24, 48 and 72 hours with B. pertussis, B. parapertussis, B. bronchiseptica cultures, as well as Haemophilus influenzae strain. The fragmentation of IgA was studied by immunielectrophoresis with antisera to alpha-chain, to Fab alpha + Fc alpha, to Fab alpha and with antisera to light chains corresponding to the type of paraprotein. B. pertussis and B. parapertussis were found to have subclass-unspecific IgA protease which splitted off a cathode fragment, similar to Fab-fragment and, probably, corresponding to the variable domain of alpha-chain (Fv), after 48-hour incubation. Similar IgA protease was detected in H. influenzae, found to have classical IgA1 protease as well. All Bordetella species under study splitted off anode components from IgA paraproteins of both subclasses. These components, containing the determinants of heavy and light IgA chains, were either IgA - alpha I-antitrypsin complexes or some IgA fragments with high electrophoretic motility. None of the strains under study splitted monoclonal IgG.
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PMID:[IgA protease activity of microbes in the genus Bordetella]. 286 69

It has previously been shown that secretory immunoglobulin A (S-IgA) influences the sorption of oral streptococci to hydroxyapatite as well as to cell surfaces. The present experiments demonstrate that bacterial IgA proteases, which cleave S-IgA in the hinge region, are capable of interfering with this mechanism. This result was obtained with an IgA1 specific protease from Haemophilus influenzae and with a protease from Clostridium ramosum that cleaves IgA1 as well as IgA2 of A2m(1) allotype. The modulation of S-IgA-mediated effects by IgA proteases were studied by means of an in vitro method which permits quantitative determination of the sorption of radiolabeled oral bacteria to hydroxyapatite beads. Other authors have suggested that IgA protease-mediated effects may be explained by a strongly reduced antigen-binding capacity of released Fab alpha fragments. Here we present evidence that streptococci, after exposure to specific S-IgA and IgA protease, are coated with Fab alpha fragments.
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PMID:Interference of IgA protease with the effect of secretory IgA on adherence of oral streptococci to saliva-coated hydroxyapatite. 304 Aug 26

In vitro production of human antibody to the Haemophilus influenzae type b capsular polysaccharide (PRP) and to tetanus toxoid (TT) and diphtheria toxoid was measured in culture supernatants of peripheral blood mononuclear cells and by enumeration of antibody secreting cells (AbSC) in an enzyme-linked immunosorbent-plaquing assay. Normal adult peripheral blood mononuclear cells stimulated with Epstein-Barr virus secreted anti-PRP antibody with a frequency of 1/552 to 1/1190 relative to total Ig secreting cells; the frequency of AbSC to tetanus toxoid (TT) was 7.5 times higher (p less than 0.05). These frequencies did not change significantly after in vivo immunization, although the isotype distribution shifted toward increased IgG for TT and increased IgG and IgA for PRP. At 8 days postimmunization, spontaneous AbSC to PRP and TT were detected; frequencies for total anti-TT AbSC again being higher than anti-PRP, but there were significantly more IgA plaques among anti-PRP AbSC. Spontaneous AbSC were suppressed in culture by pokeweed mitogen and enhanced by cyclosporine. Three wk after in vivo immunization with PRP and TT, in vitro stimulation with pokeweed mitogen, Staphylococcus aureus Cowan 1 bacteria, or antigen induced anti-TT but not anti-PRP in vitro antibody secretion, although Epstein-Barr virus induced both. These data suggest that PRP, a polysaccharide, and TT, a protein, differ in their requirements for in vitro activation with antigen and mitogens.
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PMID:In vitro human antibody production to the Haemophilus influenzae type b capsular polysaccharide. 304 Aug 62

The serum antibody response to Haemophilus influenzae type b capsular polysaccharide or its protein conjugate vaccine (PRP and PRP-D, respectively) was studied in 28 children initially immunized at the age of 24 mo with either vaccine and in 10 children immunized for the third time with PRP-D at the age of 18 mo. The methods used were isotype-resolving enzyme immunoassay, Farr-type radioimmunoassay, and the in vitro bactericidal activity (BCA) test. Immunization with PRP evoked a higher proportion of IgA antibodies than did either the first or third dose of PRP-D, whereas the latter vaccine evoked a somewhat higher IgG response, but the differences were not statistically significant. In all groups the IgG antibody responses were predominantly IgG1, with the mean proportions being 82.2%, 84.2%, and 65.9% in the PRP, first-dose PRP-D, and third-dose PRP-D groups, respectively. Postimmunization antibodies were functionally active in the BCA test.
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PMID:Isotype distribution and bactericidal activity of antibodies after immunization with Haemophilus influenzae type b vaccines at 18-24 months of age. 305 31

Serum IgG contains 4 subclasses, IgG1 (60-66%), IgG2 (20-30%), IgG3 (less than or equal to 5%) and IgG4. Individual subclasses vary with respect to their physicochemical and biological properties. IgG subclass concentrations in serum are age dependent. IgG1 and IgG3 reach near to adult levels around the age of 3, IgG2 and IgG4 after the age of 6. Antibodies of certain specificities generally belong to a certain isotype (subclass) due to the isotype restriction. Patients with subclass deficiencies often suffer from recurrent infections. Those with IgG2 deficiency (often occurring with IgA and IgG4 deficiency) develop recurrent infection of the upper and lower respiratory tract often caused by pyogenic microorganisms (Haemophilus, Pneumococcus). Since early initiation of IVIG substitution therapy has a beneficial effect on long term prognosis the importance of early diagnosis is apparent.
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PMID:[Clinico-immunologic aspects of IgG subclass deficiency]. 305 27

Km allotype antigens are serologic markers expressed on kappa light chains of human immunoglobulins. To determine whether th Km phenotype of an individual is related to his ability to make antibodies to polysaccharide antigens, we correlated the Km allotypes of 129 healthy caucasian adults with the concentrations of specific antibodies to three bacterial polysaccharide antigens after immunization. The 14 individuals expressing the Km(1) allotype had lower concentrations of IgG, IgM, and IgA antibodies by enzyme-linked immunosorbent assay and total antibody by radioimmunoassay to Haemophilus influenzae type b and Neisseria meningitidis group C capsular polysaccharides when compared with the 115 Km(1) negative individuals. The Km-associated differences in H. influenzae type b and N. meningitidis group C antibody concentrations were confined to kappa light chain-containing antibody (P = 0.029 and 0.003, respectively). Similarly, the Km(1) positives had slightly lower kappa chain-containing Ig than the Km(1) negatives (P = 0.079). We conclude that genes in or near the kappa light chain locus play a role in the regulation of kappa-containing antibody production to some bacterial polysaccharides and perhaps to other antigens.
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PMID:Correlation of the Km(1) immunoglobulin allotype with anti-polysaccharide antibodies in Caucasian adults. 309 Jan 2

Three immunoglobulin preparations for intravenous infusion were compared in vivo to determine their relative protective capacity against several gram-negative and gram-positive pathogens. Polyglobin N is a conventional IgG concentrate. Psomaglobin N is identical in formulation to Polyglobin N but is prepared from the plasma of donors who have naturally high levels of antibody to lipopolysaccharide antigens of Pseudomonas aeruginosa. IgGMA is a conventional IgG concentrate containing 12% IgG and 16% IgA. In a murine model of burn wound sepsis the three IgG preparations were similarly protective against three or ten strains of P. aeruginosa. Psomaglobin N and Polyglobin N were significantly (p less than or equal to 0.015) more protective than IgGMA against six of ten and three of ten strains of P. aeruginosa, respectively. In a murine model of Streptococcus pneumoniae type 3 pneumonia, the three Ig preparations were similarly protective. IgGMA was significantly more protective (p less than or equal to 0.025) than Psomaglobin N and Polyglobin N against Salmonella typhimurium in murine peritonitis. However, the mean protective dose (PD50) of the two later preparations was less than or equal to 20 mg/kg body weight. In models of peritonitis both Psomaglobin N and Polyglobin N were more protective than IgGMA (p less than or equal to 0.004) against Haemophilus influenzae b, Klebsiella pneumoniae, Serratia marcescens 06:H3 and group B Streptococcus types 1b and 1c. Psomaglobin N and ciprofloxacin were employed to treat established polymicrobial murine burn wound sepsis resulting from contamination of the burn site with mixtures of P. aeruginosa and Staphylococcus aureus.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Prevention of gram-negative and gram-positive infections with 3 intravenous immunoglobulin preparations and therapy of experimental polymicrobial burn infection with intravenous Pseudomonas immunoglobulin G and ciprofloxacin in an animal model]. 311 21

Normal serum IgA and secretory IgA (sIgA) of subclass IgA1 were isolated from pooled human serum and milk, respectively. They were tested for their susceptibility to bacterial IgA proteases from Haemophilus influenzae, Streptococcus pneumoniae, Neisseria gonorrhoeae, and Neisseria meningitidis that cleave IgA of only the IgA1 subclass. They were also tested for susceptibility to a novel IgA-protease from Clostridium ramosum that cleaves IgA of the IgA1 as well as the IgA2 subclass of the A2m(1) allotype. Both normal serum IgA1 and sIgA1 exhibited resistance to most IgA proteases. The one exception was the IgA protease from C. ramosum which readily cleaved both the serum IgA1 and sIgA1 into Fab and Fc fragments. Secretory component (SC) had nothing to do with the resistance of these IgAs. The resistance of these IgAs to most of the IgA proteases was found to be due to their enzyme-neutralizing antibody activity, since the Fab but not the Fc fragment of sIgA1 showed enzyme-inhibitory activity against these IgA proteases. Similar enzyme-neutralizing antibody activity was found in the pepsin-digested normal serum IgG-(Fab')2 fragment. These results indicate that the induction of the enzyme-neutralizing antibodies against the bacterial IgA proteases took place not only in mucosal sIgA but also in serum IgA and IgG. No enzyme-neutralizing antibody activity against the novel IgA-protease of C. ramosum was detected in any immunoglobulin preparations used in the present study or in the serum of a patient who carries the IgA protease-producing strain of C. ramosum in his feces.
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PMID:Resistance of normal serum IgA and secretory IgA to bacterial IgA proteases: evidence for the presence of enzyme-neutralizing antibodies in both serum and secretory IgA, and also in serum IgG. 312 62

Levels of antibodies against Haemophilus influenzae type b capsular polysaccharide were determined in acute-phase and convalescent-phase serum samples obtained from 21 children with invasive H. influenzae type b infections and from 44 children vaccinated with two H. influenzae type b vaccines. Amounts of immunoglobulin G (IgG), IgM, and IgA antibodies were measured by direct and indirect enzyme-linked immunosorbent assay (ELISA), and the total amount of antibodies was measured by radioimmunoassay (RIA). Results obtained by ELISA were calculated by multiple-point parallel-line comparison and by endpoint analysis. A very good correlation was obtained between direct and indirect ELISA values. In the lower range of antibody concentrations, the correlation between ELISA values obtained by endpoint analysis and those obtained by multiple-point parallel-line comparison was poor, since the latter method of calculation yielded values of up to 1 microgram/ml in sera that were negative according to endpoint analysis. These sera with negative endpoint titers also had undetectable or very low antibody concentrations as measured by RIA. Consistent with this finding, in acute-phase and prevaccination sera with undetectable or low antibody concentrations as measured by RIA, ELISA values calculated by multiple-point parallel-line comparison were much higher. In sera with higher antibody concentrations, however, parallel-line comparisons showed good correlation between RIA and ELISA values. Although no reference method for measuring true antibody concentrations is available, ELISA values as calculated by multiple-point parallel-line comparison appear to overestimate antibody concentrations in sera containing low antibody concentrations, whereas ELISA values obtained by endpoint analysis are less well correlated with RIA values at higher concentrations.
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PMID:Comparison between radioimmunoassay and direct and indirect enzyme-linked immunosorbent assays for determination of antibodies against Haemophilus influenzae type b capsular polysaccharide. 323 Jan 33

Haemophilus somnus expresses two types of receptors that bind to the Fc region of bovine IgG, IgA and IgM. In this study, the relationship between these two types of Fc receptors is characterized. The high molecular mass receptors (350, 270 and 120 kDa) were secreted into the culture medium and were also in the insoluble protein fraction of the culture medium. The 41 kDa Fc receptor, which is a major outer-membrane protein, was only present in the insoluble protein fraction. Peptide mapping of the two types of Fc receptors suggests that the 41 kDa receptor is related to the high molecular mass receptor complex. Disulphide linkage is unlikely to be the mechanism of association of the 41 kDa receptor with the high molecular mass receptors since reducing agents had no effect on separating the individual receptors. Although the 41 kDa receptor is a major protein in the outer membrane of H. somnus, it does not react with convalescent bovine sera in Western blots. In contrast, convalescent bovine sera reacts intensely with the high molecular mass receptors in Western blots.
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PMID:Characterization of two Haemophilus somnus Fc receptors. 324 93


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