Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0043167 (pertussis)
 19,595 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The surface antigen, P69 of Bordetella pertussis, an N-terminal fragment of the precursor protein, P93, is likely to be an important component of future subunit vaccines against whooping cough. We have expressed several defined N-terminal fragments of P93 in E. coli and compared their electrophoretic mobilities with that of purified P69 from B. pertussis. These experiments show that P69 is considerably smaller than the 69 kD originally estimated from its gel mobility and is probably 60.4 kD in size. Our initial plasmids expressed only very low levels of this antigen. We diagnosed the limiting factor to be a poor ribosome binding site (RBS) by demonstrating a large stimulation of expression on a two-cistron plasmid. The limitation of expression could be completely overcome by only two base changes close to the initiation codon, resulting in a further increase in expression of P69 at levels to 30-40% total cell protein. Although the protein accumulated as insoluble inclusion bodies, it could be solubilized by guanidinium chloride.
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PMID:Protective surface antigen P69 of Bordetella pertussis: its characterization and very high level expression in Escherichia coli. 136 30

Single base deletions in the lac promoter which reduced the 18bp spacing between the -35 and -10 homology regions to 17bp, increased the strength of the promoter. A single base substitution (T----G) in the -35 region to generate the consensus sequence TTG-ACA increased the strength further and no longer required a 17bp spacing. The mutated lac promoter was as powerful as a shorter form of the tac promoter which lacked two AT-rich regions upstream of the -35 region, and expressed the P69 surface antigen (pertactin) of Bordetella pertussis to 30-40% total cell protein and tetanus toxin fragment C to 16-20% total cell protein.
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PMID:High level heterologous expression in E. coli using mutant forms of the lac promoter. 204 79

In most developing countries hepatitis B virus is endemic and prevention has to be carried out early in life and on a mass scale. In these regions, simultaneous administration of multiple antigens is normal practice. We have therefore, investigated the interaction of hepatitis B vaccine with DTP-Polio vaccine. Studies include the immune response post one and two injections to diphtheria and tetanus toxoid, pertussis and hepatitis B surface antigen. The vaccines were given simultaneously or not at a 6 months interval. The immune response to HBsAg vaccine and DTP-Polio vaccine injected simultaneously was equal to the immune response observed after administration of vaccines alone. Moreover, no adverse reactions were noted. This trial also demonstrated that immunization with two doses of DTP-Polio vaccine, containing 30 Lf of diphtheria and tetanus toxoids, at a 6 months interval is sufficient to obtain a very good immune response.
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PMID:Simultaneous administration of diphtheria/tetanus/pertussis/polio vaccine and hepatitis B vaccine in a simplified immunization programme. 288 21

Bordetella pertussis strain UT25 was isolated on Bordet-Gengou(B-G) agar from a child with whooping cough in 1977. Derivative strains were isolated from UT25 by serial passages on Trypticase Soy Agar (TSA) containing blood,followed by serial passages on plain TSA. At passage 69, UT25 was subcultured in parallel on TSA and B-G. For experiments, strains were grown in defined liquid medium, adjusted to a standard turbidity, and tested in parallel. Tests were performed to detect changes in immunogenicity, production of dermonecrotic toxin, histamine sensitizing ability, serologic properties, infectivity for mice by the intranasl route, production of adenylate cyclase, patterns of outer membrane proteins. Notable changes occurred in the properties of UT25 at passage 16, just when stable growth on blood-fresh medium was established. After 5 additional passages on TSA, however, the strain resembled the original isolate. At about passage 45, biological activity began to decline, and by passage 60 most biological activities were sharply diminished or undetectable. No recovery of biological activity was observed during a further 15 passages on TSA. Strains derived from the sixty-ninth passage of UT25, after passage on B-G for 5 subcultures, showed partial recovery of biological activity. Ten additional subcultures on B-G yielded strains which showed even higher biological activity. Fluorescent antibody staining confirmed that all strains studied were B. pertussis, and maintained reactive surface antigen(s), in spite of loss of agglutinability in specific antiserum.
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PMID:Variability in derivative strains of Bordetella pertussis. 624 89

The surface antigen P.69/pertactin of Bordetella pertussis has been expressed using the polyhedron promoter of baculovirus in cultured insect cells. Either full-length or truncated prn DNA was used to express P.69 pertactin. The full-length gene gave rise to low levels of P.93 precursor protein, some of which was processed to P.69. The shortened prn expressed P.69 pertactin directly at levels up to 3.5 mg per litre. P.69 vaccinated animals were protected against aerosol challenge with virulent B. pertussis bacteria.
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PMID:Expression of P.69/pertactin from Bordetella pertussis in a baculovirus/insect cell expression system: protective properties of the recombinant protein. 819 Sep 94

A recombinant hepatitis B vaccine was administered to over 5000 infants in a prospective, randomized and blinded study. Infants were given either recombinant hepatitis B vaccine (Engerix-B, SmithKline Beecham Pharmaceuticals, 10 micrograms dose-1) or a Haemophilus influenzae type b (Hib) conjugate vaccine at 2, 4 and 6 months of age simultaneously with diphtheria-tetanus-pertussis and oral polio vaccines. Adverse reactions were ascertained by parental reports and interviews, and review of medical records. Blood specimens collected from 269 infants given hepatitis B vaccine were assayed for antibody to hepatitis B surface antigen (anti-HBs) by enzyme immunoassay. Infants given hepatitis B vaccine experienced low rates of adverse reactions that were similar or lower than the rates in infants given Hib conjugate vaccine. The geometric mean anti-HBs concentrations were 9.6 mIU ml-1 after one dose, 333 mIU ml-1 after two doses and 1812 mIU ml-1 after three doses (99% had levels > or = 10 mIU ml-1). Antibody responses to diphtheria and tetanus toxoids were unaffected by simultaneous administration of hepatitis B or Hib conjugate vaccine. Engerix-B vaccine was safe and immunogenic when given with other routine childhood immunizations at 2, 4 and 6 months of age, and should provide long-term protection against hepatitis B virus infection.
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PMID:Safety and immunogenicity of a recombinant hepatitis B vaccine administered to infants at 2, 4 and 6 months of age. The Kaiser-UCLA Vaccine Study Group. 881 29

To determine hepatitis B immunisation rates in infants from ethnic groups with hepatitis B surface antigen chronic carrier prevalence over 5 per cent, a questionnaire was sent to all Maternal and Child Health Centres in Victoria, requesting information on the hepatitis B and diphtheria-tetanus-pertussis (DTP) or combined diphtheria-tetanus (CDT) immunisation status for all infants born between 1 July 1992 and 30 June 1993 and at risk of hepatitis B infection because of maternal ethnicity. We received data on 3611 of 5744 infants (62.9 per cent) in targeted ethnic groups. Of these, 12.8 per cent had not received hepatitis B vaccine, and 81.6 per cent, 76.8 per cent and 64.0 per cent had received at least one, two and three doses respectively, while 84 per cent had received at least three doses of DTP vaccine and/or CDT vaccine. Coverage with DTP or CDT was higher than for hepatitis B vaccine (P < 0.001), and coverage was better in areas with a higher percentage of infants in high-prevalence ethnic groups (P < 0.001). Changes in the program in Victoria in terms of timing of the first dose of vaccine plus greater attention to follow-up may lead to improved hepatitis B immunisation rates among infants in targeted ethnic groups. Adoption of universal infant hepatitis B immunisation, by increasing familiarity with hepatitis B vaccine, is likely to be the best way to increase immunisation coverage for these infants.
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PMID:Hepatitis B immunisation rates among infants in ethnic groups with high prevalences of hepatitis B surface antigen carriers. 927 Jan 56

A study of the immunogenicity of a recombinant hepatitis B vaccine was conducted among 385 Egyptian infants, 191 (49.6%) of whom were born to mothers with moderately active Schistosoma mansoni infection (mean egg count = 224 eggs/g of feces). All mothers were seronegative for hepatitis B surface antigen (HBsAg) and hepatitis B e antigen. Infants were vaccinated with a 2.5-microg dose of this vaccine, given along with diphtheria, tetanus, and pertussis (DTP) vaccine, at the ages of two, four, and six months. Serum samples taken from each infant at nine months of age were tested for HBsAg, antibody to hepatitis B core antigen, and quantitatively for antibody to hepatitis B surface antigen (anti-HBs). There was no significant difference (P = 0.1) between anti-HBs titers in infants of S. mansoni-infected mothers (mean = 539 mIU/ml) and in infants of noninfected mothers (mean = 377 mIU/ml). This study shows that there was no apparent effect of maternal schistosomiasis infection on the immune response of these infants to vaccination.
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PMID:Immunogenicity of recombinant hepatitis B vaccine among infants of mothers with active schistosomiasis. 928 16

Infants born to HBsAg- (hepatitis B surface antigen) carrier mothers are highly likely to become chronic hepatitis B (HB) carriers themselves unless their status is recognised at birth and they are immunised with three doses of HB vaccine, the first within 48 hours of birth, concurrent with hepatitis B immune globulin (HBIG). This study was designed to determine how many infants born in Victoria to carrier mothers completed three doses of HB vaccine. We sent the names of all infants of HBsAg-carrier mothers notified in Victoria between 1.7.91 and 30.6.92 to the appropriate local government immunisation providers and requested information on how many doses of HB vaccine, DTP (diphtheria-tetanus-pertussis) or CDT (combined diphtheria-tetanus), and OPV (oral polio vaccine) they had received. The HBsAg-carrier prevalence of women giving birth in Victoria in 1991-92 was at least 0.52%. Of the 336 infants notified, 239 (71.1%) were recorded in local government records. Of these 239, 90.8% received at least two doses and 80.8% received at least three doses of hepatitis B vaccine. There was no significant difference in the number who received three doses of HB vaccine compared with three doses of DTP or CDT vaccine. Of the entire cohort of 336, only 57.4% were documented as being completely immunised against hepatitis B. HB immunisation coverage for these infants needs to be improved. The high rate of loss to follow-up, especially between the maternity hospital and the community, is disturbing. Mechanisms for intensive prospective follow-up of these infants should be developed to prevent loss to follow-up and to encourage full immunisation against HB. Improving HB immunisation coverage of infants in high HBsAg-prevalence ethnic groups and introduction of universal infant HB immunisation may lead to increased coverage of infants of carriers by serving as back-up mechanisms for those lost to follow-up.
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PMID:Hepatitis B immunisation coverage of infants born to chronic carrier mothers in Victoria. 948 90

The identification of stromal cell-derived factor (SDF)-1alpha as a chemoattractant for human progenitor cells suggests that this chemokine and its receptor might represent critical determinants for the homing, retention, and exit of precursor cells from hematopoietic organs. In this study, we investigated the expression profile of CXCR4 receptor and the biological activity of SDF-1alpha during megakaryocytopoiesis. CD34(+) cells from bone marrow and cord blood were purified and induced to differentiate toward the megakaryocyte lineage by a combination of stem-cell factor (SCF) and recombinant human pegylated megakaryocyte growth and development factor (PEG-rhuMGDF). After 6 days of culture, a time where mature and immature megakaryocytes were present, CD41(+) cells were immunopurified and CXCR4mRNA expression was studied. High transcript levels were detected by a RNase protection assay in cultured megakaryocytes derived from cord blood CD34(+) cells as well as in peripheral blood platelets. The transcript levels were about equivalent to that found in activated T cells. By flow cytometry, a large fraction (ranging from 30% to 100%) of CD41(+) cells showed high levels of CXCR4 antigen on their surface, its expression increasing in parallel with the CD41 antigen during megakaryocytic differentiation. CXCR4 protein was also detected on peripheral blood platelets. SDF-1alpha acts on megakaryocytes by inducing intracellular calcium mobilization and actin polymerization. In addition, in in vitro transmigration experiments, a significant proportion of megakaryocytes was observed to respond to this chemokine. This cell migration was inhibited by pertussis toxin, indicating coupling of this signal to heterotrimeric guanine nucleotide binding proteins. Although a close correlation between CD41a and CXCR4 expession was observed, cell surface markers as well as morphological criteria indicate a preferential attraction of immature megakaryocytes (low level of CD41a and CD42a), suggesting that SDF-1alpha is a potent attractant for immature megakaryocytic cells but is less active on fully mature megakaryocytes. This hypothesis was further supported by the observation that SDF-1alpha induced the migration of colony forming unit-megakaryocyte progenitors (CFU-MK) and the expression of activation-dependent P-selectin (CD62P) surface antigen on early megakaryocytes, although no effect was observed on mature megakaryocytes and platelets. These results indicate that CXCR4 is expressed by human megakaryocytes and platelets. Furthermore, based on the lower responses of mature megakaryocytes and platelets to SDF-1alpha as compared with early precursors, these data suggest a role for this chemokine in the maintenance and homing during early stages of megakaryocyte development. Moreover, because megakaryocytes are also reported to express CD4, it becomes important to reevaluate the role of direct infection of these cells by the human immunodeficiency virus (HIV)-1 in HIV-1-related thrombocytopenia.
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PMID:Phenotypic and functional evidence for the expression of CXCR4 receptor during megakaryocytopoiesis. 1002 79


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