Bovis BCG (bovi + bcg)

Distribution by Scientific Domains
Life Sciences69%
Medical Sciences30%

Kinds of Bovis BCG

  • m. bovi bcg
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  • mycobacterium bovi bcg
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    Selected Abstracts

    Comparative proteome analysis of culture supernatant proteins from virulent Mycobacterium tuberculosis H37Rv and attenuated M. bovis BCG Copenhagen

    ELECTROPHORESIS, Issue 19-20 2003
    Jens Mattow
    Abstract A comprehensive analysis of culture supernatant (CSN) proteins of Mycobacterium tuberculosis H37Rv was accomplished by combination of two-dimensional electrophoresis (2-DE), mass spectrometry, and N -terminal sequencing by Edman degradation. Analytical 2-DE gels resolved approximately 1250 protein spots from CSN of M. tuberculosis H37Rv, 381 of which were identified by mass spectrometry and/or Edman degradation. This study revealed 137 different proteins, 42 of which had previously been described as secreted. Comparative proteome analysis of CSN from virulent M. tuberculosis H37Rv and attenuated Mycobacterium bovis BCG Copenhagen identified 39 M. tuberculosis- specific spots containing 27 different proteins, representing candidate antigens for novel vaccines and diagnostics in tuberculosis. These included five proteins encoded by open reading frames absent from M. bovis BCG, e.g., early secretory antigen target (Esat6), as well as 22 novel differential proteins, such as acetyl-CoA C-acetyltransferase (Rv0243) and two putative Esat6-like proteins (Rv1198, Rv1793). [source]

    Apparent growth phase-dependent phosphorylation of malonyl coenzyme A:acyl carrier protein transacylase (MCAT), a major fatty acid synthase II component in Mycobacterium bovis BCG

    FEMS MICROBIOLOGY LETTERS, Issue 1 2003
    Indrajit Sinha
    Abstract Probing protein extracts from exponentially growing and stationary phase cultures of Mycobacterium bovis BCG with anti-phospho amino acid antibodies revealed a 31-kDa anti-phospho threonine antibody-reactive protein specific to growing culture. The corresponding protein was purified via two-dimensional gel electrophoresis and identified via mass spectrometry to be malonyl coenzyme A:acyl carrier protein transacylase (MCAT), a component of the fatty acid biosynthetic pathway. MCAT tagged with histidine reacted with anti-phospho threonine antibody and was positive in an in-gel chemical assay for phospho proteins. Analysis of the growth phase dependence of MCAT-His phosphorylation and protein levels showed that phosphorylated MCAT-His can be detected only in growing culture. In contrast, MCAT-His protein level was growth phase-independent. These results suggest that MCAT may be a substrate of a protein kinase and phosphatase, and that aspects of fatty acid synthesis in tubercle bacilli are regulated by protein phosphorylation. [source]

    Accelerated induction of mycobacterial antigen-specific CD8+ T cells in the Mycobacterium tuberculosis -infected lung by subcutaneous vaccination with Mycobacterium bovis bacille Calmette,Guérin

    IMMUNOLOGY, Issue 4 2009
    Dilara Begum
    Summary Both CD4+ and CD8+ T cells are important in protection against Mycobacterium tuberculosis infection. To evaluate the effect of vaccination with Mycobacterium bovis bacille Calmette,Guérin (BCG) on the CD8+ T-cell response to pulmonary M. tuberculosis infection, we analyzed the kinetics of CD8+ T cells specific to the mycobacterial Mtb32a309,318 epitope, which is shared by M. tuberculosis and M. bovis BCG, in the lung of mice infected with M. tuberculosis. The CD8+ T cells were detected by staining lymphocytes with pentameric major histocompatibility complex (MHC) class I H-2Db,Mtb32a209,318 peptide complex and were analysed by flow cytometry. Mtb32a-specific CD8+ T cells became detectable on day 14, and reached a plateau on day 21, in the lung of M. tuberculosis -infected unvaccinated mice. Subcutaneous vaccination with M. bovis BCG in the footpads induced Mtb32a-specific CD8+ T cells in the draining lymph nodes (LNs) on day 7 and their numbers further increased on day 14. When M. bovis BCG-vaccinated mice were exposed to pulmonaryinfection with M. tuberculosis 4 weeks after vaccination, the Mtb32a-specific CD8+ T cells in the infected lung became detectable on day 7 and reached a plateau on day 14, which was 1 week earlier than in the unvaccinated mice. The pulmonary CD8+ T cells from the BCG-vaccinated M. tuberculosis -infected mice produced interferon-, in response to Mtb32a209,318 peptide on day 7 of the infection, whereas those of unvaccinated mice did not. The results demonstrate that induction of mycobacterial antigen-specific protective CD8+ T cells in the M. tuberculosis -infected lung is accelerated by subcutaneous vaccination with M. bovis BCG. [source]

    Effect of recombinant Rv1009 protein on promoting the growth of Mycobacterium tuberculosis

    JOURNAL OF APPLIED MICROBIOLOGY, Issue 4 2008
    X. Wu
    Abstract Aims:, To determine whether resuscitation-promoting factor (RPF) from Mycobacterium tuberculosis can promote mycobacterial growth and shorten culture time. Method and Results:, We cloned, expressed and purified an RPF from M. tuberculosis, Rv1009 protein and subsequently studied the biological activity of the recombinant Rv1009 (rRv1009) in liquid and on solid media. Our results indicate that the molecular weight of rRv1009 protein expressed in Escherichia coli BL21 was approximately 39 kDa. At picomolar and micromolar concentrations, rRv1009 protein could increase the optical density of freeze-dried Mycobacterium bovis BCG three to fivefold in Middlebrook 7H9 medium, stimulate the growth of viable mycobacteria on solid medium, and shorten positive growth detection time of a small number of M. tuberculosis in BACTEC 960 medium. Conclusions:, The rRv1009 could promote proliferation of mycobacteria. It may be useful for culture of mycobacteria presented in clinical samples. Significance and Impact of the Study:, rRv1009 protein can be used as a growth-promoting reagent of mycobacteria in the medium to shorten the time of culture. [source]

    Loss of RD1 contributed to the attenuation of the live tuberculosis vaccines Mycobacterium bovis BCG and Mycobacterium microti

    MOLECULAR MICROBIOLOGY, Issue 3 2002
    Alexander S. Pym
    Summary Although large human populations have been safely immunized against tuberculosis with two live vaccines, Mycobacterium bovis BCG or Mycobacterium microti, the vole bacillus, the molecular basis for the avirulence of these vaccine strains remains unknown. Comparative genomics has identified a series of chromosomal deletions common to both virulent and avirulent species but only a single locus, RD1, that has been deleted from M. bovis BCG and M. microti. Restoration of RD1, by gene knock-in, resulted in a marked change in colonial morphology towards that of virulent tubercle bacilli. Three RD1-encoded proteins were localized in the cell wall, and two of them, the immunodominant T-cell antigens ESAT-6 and CFP-10, were also found in culture supernatants. The BCG::RD1 and M. microti::RD1 knock-ins grew more vigorously than controls in immunodeficient mice, inducing extensive splenomegaly and granuloma formation. Increased persistence and partial reversal of attenuation were observed when immunocompetent mice were infected with the BCG::RD1 knock-in, whereas BCG controls were cleared. Knocking-in five other RD loci did not affect the virulence of BCG. This study describes a genetic lesion that contributes to safety and opens new avenues for vaccine development. [source]

    Immunotherapy with live BCG plus heat killed Leishmania induces a T helper 1-like response in American cutaneous leishmaniasis patients

    PARASITE IMMUNOLOGY, Issue 2 2000
    Maira Cabrera
    Previous work has shown that American cutaneous leishmaniasis (ACL) patients treated with viable BCG plus heat killed promastigotes of Leishmania amazonensis show the same rate of cure as patients receiving conventional chemotherapy. The treatment is safe and economical, but the immunological correlates of cure have not been examined. In the present study, T cell responses have been analysed in 43 ACL patients, including patient groups sampled before and after therapy, and in 10 endemic controls. Lymphocyte proliferation, interferon (IFN)-, and interleukin (IL)-5 responses to crude antigen (L. amazonensis, MEL; Mycobacterium tuberculosis PPD; M. bovis BCG) stimulation, and serum IL-5 levels, were analysed. In endemic volunteers, proliferative responses to BCG were high and IFN-, responses low. In contrast, localized cutaneous (LCL) and mucocutaneous (MCL) patients showed low proliferative and high IFN-, responses to BCG. Treatment enhanced the IFN-, response and further decreased the proliferative response to BCG, especially in MCL patients. LCL and MCL patients showed an increase in proliferative and IFN-, responses to MEL with treatment, but the response was not exaggerated in MCL patients, either before or after treatment, compared to LCL patients. IL-5 production was low in T cell assays, and > 62% of untreated patients had very low serum IL-5 levels. There were no significant changes in serum IL-5 with treatment. Overall results show enhanced antigen-specific IFN-, responses to the two components of the immunotherapy, live M. bovis BCG and heat killed L. amazonensis, which is consistent with a shift in balance of T cell response towards a T helper 1 response and clinical cure mediated by IFN-,. [source]

    Generation of self-renewing immature dendritic cells from mouse spleen that can take up mycobacteria and present antigens to T cells

    APMIS, Issue 10 2010
    RUBINA PAL
    Pal R, Marwaha S, Pepponi I, Mann JFS, Paul MJ, Reljic R. Generation of self-renewing immature dendritic cells from mouse spleen that can take up mycobacteria and present antigens to T cells. APMIS 2010; 118: 729,38. Dendritic cells (DC) play a key role in driving the adaptive immune response to Mycobacterium tuberculosis (MTB), the causative pathogen of tuberculosis (TB). However, studying these important yet very sparse immune cells in the context of MTB pathogenesis is severely restricted by the lack of suitable cell lines and the complexity of culturing of DC progenitors, usually obtained from the bone marrow. However, significant advances have been made towards generating long-term DC cultures from various lymphoid tissues. Here, we report the evidence for generating a long-term, self-renewing DC culture from the Balb/c mouse spleen. We demonstrate that these cells, termed IDC-3, have a myeloid DC origin, i.e. they are CD11c+CD11b++CD8-,,F4/80+/, and that they also display a phenotype MHC-II+CD16/32++CD80+/,CD86+, indicating that they are immature DC. Following incubation with Mycobacterium bovis BCG (Bacillus Calmette Guerin), the IDC-3 efficiently took up bacteria and acquired the morphology of mature DC. Importantly though, when IDC-3 were pre-stimulated with a mycobacterial antigen in vitro, they were able to induce proliferation of T lymphocytes from mice immunized with the same antigen. The T-cell stimulatory potential of IDC-3 was further enhanced when the cells were co-stimulated with an anti-CD40 mAb. We therefore suggest that the IDC-3 culture system could be a useful tool for studying the interaction of DC with mycobacteria. [source]

    The mannose cap of mycobacterial lipoarabinomannan does not dominate the Mycobacterium,host interaction

    CELLULAR MICROBIOLOGY, Issue 4 2008
    B. J. Appelmelk
    Summary Pathogenic mycobacteria have the ability to persist in phagocytic cells and to suppress the immune system. The glycolipid lipoarabinomannan (LAM), in particular its mannose cap, has been shown to inhibit phagolysosome fusion and to induce immunosuppressive IL,10 production via interaction with the mannose receptor or DC-SIGN. Hence, the current paradigm is that the mannose cap of LAM is a crucial factor in mycobacterial virulence. However, the above studies were performed with purified LAM, never with live bacteria. Here we evaluate the biological properties of capless mutants of Mycobacterium marinum and M. bovis BCG, made by inactivating homologues of Rv1635c. We show that its gene product is an undecaprenyl phosphomannose-dependent mannosyltransferase. Compared with parent strain, capless M. marinum induced slightly less uptake by and slightly more phagolysosome fusion in infected macrophages but this did not lead to decreased survival of the bacteria in vitro, nor in vivo in zebra fish. Loss of caps in M. bovis BCG resulted in a sometimes decreased binding to human dendritic cells or DC-SIGN-transfected Raji cells, but no differences in IL-10 induction were observed. In mice, capless M. bovis BCG did not survive less well in lung, spleen or liver and induced a similar cytokine profile. Our data contradict the current paradigm and demonstrate that mannose-capped LAM does not dominate the Mycobacterium,host interaction. [source]

    Coronin is involved in uptake of Mycobacterium bovis BCG in human macrophages but not in phagosome maintenance

    CELLULAR MICROBIOLOGY, Issue 12 2001
    Stephanie Schüller
    By applying density gradient electrophoresis (DGE) to human macrophages infected with Mycobacterium bovis BCG, we were able to separate three different bacterial fractions representing arrested phagosomes, phagolysosomes and mycobacterial clumps. After further purification of the phagosomal population, we found that isolated phagosomes containing live BCG were arrested in maturation as they exhibited only low amounts of the lysosomal glycoprotein LAMP-1 and processing of the lysosomal hydrolase cathepsin D was blocked. In addition, low amounts of MHC class I and class II molecules and the absence of HLA-DM suggest sequestration of mycobacterial phagosomes from antigen-processing pathways. We further investigated the involvement of the actin-binding protein coronin in intracellular survival of mycobacteria and showed that human coronin, as well as F-actin, were associated with early stages of mycobacterial phagocytosis but not with phagosome maintenance. Therefore, we conclude that the unique DGE migration pattern of arrested phagosomes is not as a result of retention of coronin, but that there are other proteins or lipids responsible for the block in maturation in human macrophages. [source]

    Vaccination of neonatal calves with Mycobacterium bovis BCG induces protection against intranasal challenge with virulent M. bovis

    CLINICAL & EXPERIMENTAL IMMUNOLOGY, Issue 1 2005
    J. C. Hope
    Summary Vaccination of neonates with Mycobacterium bovis bacillus Calmette,Guérin (BCG) may be a strategy that overcomes reduced vaccine efficacy associated with exposure to environmental mycobacteria in humans and cattle. Preliminary comparisons indicated that 2-week-old calves produced an immune response to vaccination at least as intense as that observed in adults. Subsequently, five gnotobiotic hysterotomy derived calves aged 1 day were inoculated with BCG and 3 months later were challenged intranasally with virulent M. bovis. The number of tissues with lesions and the pathological extent of these lesions was reduced significantly in vaccinates. Furthermore, lesions were evident in the lung or associated chest lymph nodes of four of five controls but none of five vaccinates. BCG vaccination reduced significantly the level of bacterial colonization. However, lesions in the head associated lymph nodes were observed in three of five BCG-vaccinated cattle. Levels of interferon gamma (IFN-,) detected by enzyme-linked immunosorbent assay (ELISA) or enzyme-linked immunospot (ELISPOT) in individual vaccinated animals at challenge did not correlate with subsequent resistance and in general immune responses post-challenge were lower in vaccinated calves. Low IL-10 responses were evident but IL-4 was not detected. Responses to ESAT-6 and/or CFP-10 were evident in four of four control calves that had lesions. Two of the BCG vaccinates with lesions did not produce a response to ESAT-6 and CFP-10, indicating that these antigens did not distinguish vaccinated immune animals from vaccinated animals with lesions. Overall, vaccination of neonatal calves with BCG induced significant protection against disease and has potential as a strategy for the reduction of the incidence of bovine tuberculosis. [source]