Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:O95477 (membrane-bound)
 29,236 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

After stimulation by ovalbumin + Bordetella pertussis, rat peritoneal mast cells can form rosettes with antigen-coated erythrocytes. This phenomenon is inhibited by previous incubation of mast cells with antigen; it is attributed to apparition of membrane-bound anaphylactic antibody. The variations of percentage of rosette forming mast cells during the course of immunization are reported and compared with P.C.A. titers.
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PMID:[Mast-cell rosettes in the immunized rat]. 18 72

The purpose of this study was to identify and characterize functional G proteins that couple regulatory peptides with lacrimal secretory functions. Membranes were prepared from isolated rat exorbital lacrimal gland acini, and guanosine 5'-triphosphate (GTP)-dependence of adenylyl cyclase activity, known to be coupled with regulation of secretion, was measured. The guanine nucleotide GTP produced a biphasic response in the activity of membrane-bound adenylyl cyclase during a 10 min incubation with a maximum stimulation at 10(-5) mol/l GTP. Significant inhibition occurred at a dose of 10(-3) mol/l GTP, with cyclic adenosine monophosphate (cAMP) production reduced to less than basal levels. The effect of ADP-ribosylation of membrane proteins by the toxins produced by Vibrio cholera or Bordetella pertussis on lacrimal adenylyl cyclase was assessed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, autoradiography, and laser densitometry. Cholera toxin treatment of membranes resulted in dose-(0.5-100 micrograms/ml) and time-dependent (0-45 min) adenosine diphosphate (ADP)-ribosylation of two membrane proteins with M(r) values of 42,000 and 45,000. Pertussis toxin treatment resulted in the specific ADP-ribosylation of a single protein that migrates with an M(r) value of 41,000. This also was dose (0.5-25 micrograms/ml) and time dependent (0-30 min). Incorporation of 32P into the 45,000 M(r) and 42,000 M(r) proteins in the presence of 50 micrograms/ml cholera toxin was guanine nucleotide dependent, with a two- to threefold increase in labeling when the membranes were incubated with 1 or 0.5 mmol/l GTP. This effect was enhanced in the presence of the nonhydrolyzable GTP analog GTP gamma S.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Guanine nucleotide binding proteins in the dual regulation of lacrimal function. 146 5

N:NIH mice were vaccinated according to the WHO recommendations for the potency test with the Second International Standard for Pertussis Vaccine (ISPV). Blood for serological investigation was taken from the animals on day 14 post immunization before intracerebral challenge with Bordetella pertussis 18323 was done. The relationship between anti-pertussis toxin, anti-filamentous hemagglutinin and anti-adenylate cyclase antibody levels as measured by ELISA and protection from intracerebral challenge was studied. The proportion of surviving mice increased in correlation with increasing anti-PT titres; a protective level of 4 ELISA units/ml was found. Such relationship between protection against intracerebral challenge and antibody titres was not found for anti-FHA nor for anti-AC antibodies, thus suggesting that these antibodies do not play an important role in protection in this model. The excellent correlation between anti-PT antibody titres and protection suggests that the measure of anti-PT response could be a useful tool for estimating the potency of whole-cell vaccines. The development of an alternative method for testing the potency of pertussis whole-cell vaccines based on the anti-PT response should be considered.
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PMID:Pertussis whole cell vaccine: relation between intracerebral protection in mice and antibody response to pertussis toxin, filamentous hemagglutinin and adenylate cyclase. 152 Sep 70

All mice immunized with toxoid LPF and FHA molecules were found to be protected against infections by intranasal instillation of Bordetella pertussis. While a significant weight loss was observed in control mice within ten days following challenge, immunized mice were found to gain weight. Mice immunized with 20 micrograms doses of toxoid LPF were found to be also protected against intracerebral infection. FHA did not protect mice against such an infection.
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PMID:[Determination of the immune potency of lymphocyte-promoting factor (LPF) and filamentous hemagglutinin (FHA) molecules by intranasal challenge in mice]. 174 45

The Bordetella pertussis P.69 protein is an immunogen with vaccine potential. The role of this protein in pathogenesis is unclear; it has been associated with the toxic adenylate cyclase and adhesion to eukaryotic cells. For further analysis of the role of P.69 in the biology of B. pertussis, we have constructed strains which specifically lack P.69. The cloned P.69 (prn) gene of B. pertussis was insertionally inactivated with a kanamycin-resistance cassette. This inactivated gene was used to construct P.69- mutants of B. pertussis by allelic exchange using plasmid pRTP1. B. pertussis P.69- strains produced normal levels of other vir-regulated factors, including adenylate cyclase. The serotype of B. pertussis, determined by Eldering and Preston typing sera and monoclonal antibodies, was also unaffected by the presence or absence of P.69. The ability of a prn mutant to adhere to and invade HEp2 cells was not significantly different from that of its parent strain. A strain containing a mutation in fhaB was significantly less adhesive and invasive than its parent, and a prn fhaB double mutant exhibited an even greater reduction in adhesiveness and invasiveness down to levels comparable with a Vir- strain. However, strains harbouring mutations in FHA and/or P.69 were able to colonize or multiply in the murine respiratory tract, although a Vir- strain was unable to survive and proliferate in the same infection model.
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PMID:Construction and characterization of Bordetella pertussis mutants lacking the vir-regulated P.69 outer membrane protein. 178 93

The aim of this study was to examine whether there is a correlation between parental information on the child's history of whooping cough and the presence or absence of serum antibodies against two antigens of Bordetella pertussis, pertussis toxin and filamentous hemagglutinin, in nonvaccinated Swedish children. The parents of 266 Swedish children aged 1 to 4 years answered a questionnaire regarding the child's history of whooping cough, and a serum sample was obtained from the child for determination of IgG, IgM, and IgA antibodies to pertussis toxin and filamentous hemagglutinin. The study was performed from 1984 to 1986, five to seven years after the cessation of general vaccination against pertussis in Sweden; none of the children had received pertussis vaccine. Antibodies to both toxin and filamentous hemagglutinin increased with age. Of the children aged 4 years, 50% had antibodies to both antigens. Of all 266 children, 100 had antibodies to both antigens, 6 to toxin alone, and 49 to filamentous hemagglutinin alone. There was a good correlation between the presence of antibodies and a history of whooping cough. Of 91 children with a history of whooping cough, 77 had antibodies against both antigens and 13 against one antigen; only one child lacked detectable antibodies against both antigens. Of the 175 children with no history of whooping cough, 110 lacked detectable antibodies to both antigens, 23 had antibodies to both, 2 to toxin alone, and 40 to filamentous hemagglutinin alone. The data indicate that parental information on a previous history of whooping cough in their nonimmunized child is reliable, and that many infections with B. pertussis are subclinical or atypical. Exposure to other Bordetella species than B. pertussis, which is the only toxin-producing species, might be important for the development of FHA antibodies. A follow-up 2 to 4 years after the collection of serum samples of children without a history of whooping cough but with antibodies to one or both antigens indicated that serum antibodies to toxin, but not to filamentous hemagglutinin, may be protective against disease.
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PMID:History of whooping cough in nonvaccinated Swedish children, related to serum antibodies to pertussis toxin and filamentous hemagglutinin. 238 Aug 41

The enzyme-linked immunosorbent assay (ELISA) has been used for the determination of the isotype and the specificity of Bordetella pertussis serum antibodies induced by natural infection and by vaccination. In a previous study (J. Med. Microbiol., 16, 417-426 (1984)) it was shown that the presence of pertussis serum IgA antibodies could be used as an indicator of infection: IgA antibodies were not induced by vaccination nor transported from the mother to the serum of the child. In the present study ELISA was used for the determination of IgA, IgM and IgG antibodies. From the results obtained with sera from suspected pertussis cases, it was concluded that antibodies against FHA are hardly induced by infection, in contrast to anti-LPF (determined in a fetuin sandwich ELISA) and anti-LPS antibodies. In view of the lower standard deviation of the mean anti-LPF antibody titer these antibodies were studied more extensively. From a number of bacteriologically proved pertussis cases, it was shown that high levels of IgG anti-LPF antibodies were found before IgA antibodies could be detected. On the other hand, we had the impression that IgG antibodies declined more rapidly than IgA antibodies. One has, however, to take into account that IgG antibodies are transferred from mother to child. From assay of sera from infants prior to, during and two months after vaccination (ages of vaccination: 3, 4, 5 and 12 months) it was concluded that IgG anti-LPF antibodies were induced to a much lower level by DTP-polio vaccination (10 O.U. per dose) than by natural infection.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Improved serodiagnosis of whooping cough caused by Bordetella pertussis by determination of IgG anti-LPF antibody levels. 287 20

The level of antitoxin i.e. neutralizing antibodies to pertussis toxin, or lymphocytosis promoting factor, was determined in six pertussis immune globulin preparations from different manufactures. A comparison with antitoxin levels after natural pertussis disease in adults showed that pertussis immune globulins did not contain more antitoxin than convalescent phase sera, i.e. they had very low antitoxin content for specific immune globulins. Agglutinin and anti-FHA titres were relatively higher in immune globulins, probably reflecting a difference between the antibody response elicited by whole cell vaccines used for hyperimmunization in immune globulin production and by natural disease. The low antitoxin content of currently available pertussis immune globulin preparations could explain the inefficacy or conflicting results obtained with these products in prophylaxis and therapy of whooping cough.
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PMID:Antitoxin in human pertussis immune globulins. 288 31

Bordetella pertussis, the causative organism of whooping cough, produces a calmodulin-sensitive adenylate cyclase. Confer & Eaton [(1982) Science 217, 948-950] have shown that an extract from B. pertussis increases intracellular cyclic AMP levels in neutrophils and suggested that this increase is caused by the bacterial adenylate cyclase which penetrates these cells. We demonstrate in the present study that adenylate cyclase activity in lysates from lymphocytes exposed to a partially purified preparation of the bacterial enzyme has properties completely different from those of the intrinsic membrane-bound enzyme. Adenylate cyclase activity in lysates from lymphocytes exposed to the invasive enzyme is insensitive to N-ethylmaleimide, readily inactivated by acetic anhydride and relatively stable to SDS. Similar properties are exhibited by the bacterial enzyme itself. By contrast, the intrinsic membrane-bound enzyme activated by forskolin and guanosine 5'-gamma-thiotriphosphate is sensitive to N-ethylmaleimide and SDS and relatively stable to acetic anhydride. This strongly supports the notion that B. pertussis adenylate cyclase penetrates cells. Using the partially purified preparation of the invasive enzyme, we have studied the kinetics of its penetration. The intracellular catalytic activity reaches a steady state within 20 min, irrespective of enzyme or cell concentration. Steady-state levels are maintained for at least 2 h provided that the invasive enzyme is present in the incubation medium. Upon its removal, a rapid decrease (t1/2 approximately equal to 15 min) in the intracellular cyclase level is observed. This decrease reflects intracellular inactivation of the bacterial enzyme and is not caused by the release of the enzyme to the cell medium.
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PMID:The invasive adenylate cyclase of Bordetella pertussis. Properties and penetration kinetics. 288 19

Clearly, B. pertussis has evolved very elaborate mechanisms to maintain itself in the human host. Three different proteins (FHA, pertussis toxin and fimbriae) have been implicated in adherence. Furthermore, a number of toxins are produced (pertussis toxin, adenylate cyclase, dermonecrotic toxin, and tracheal cytotoxin) which destroy the clearance mechanisms of the respiratory tract, or suppress the immune response. There is evidence that B. pertussis may survive intracellularly, and the possibility that it is a facultative intracellular parasite should certainly be explored. The availability of a large number of cloned virulence genes, and a system to construct well defined mutants by allelic exchange (Stibbitz et al. 1986) will greatly facilitate the study of Bordetella virulence factors at the molecular level. It opens the possibility to construct avirulent strains, which are still able to colonize and stimulate the local immune response. Such strains may be used as live, oral vaccines, to present (heterologous) antigens to the mucosal immune system of the respiratory tract.
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PMID:Virulence factors of Bordetella pertussis. 290


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