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Braunschweig, Germany

Perez De Val B.,Autonomous University of Barcelona | Villarreal-Ramos B.,Animal Health and Veterinary Laboratories Agency Weybridge | Nofrarias M.,Autonomous University of Barcelona | Lopez-Soria S.,Autonomous University of Barcelona | And 6 more authors.
Clinical and Vaccine Immunology | Year: 2012

This is the first efficacy study using the experimental goat model, a natural host of tuberculosis (TB), to evaluate the efficacy of heterologous Mycobacterium bovis bacillus Calmette-Guérin (BCG) prime followed by boosting with a replication-deficient adenovirus expressing the antigen Ag85A (AdAg85A). Three experimental groups of 11 goat kids each were used: BCG vaccinated, BCG vaccinated and AdAg85A boosted, and nonvaccinated. Twenty-two goat kids were vaccinated with ∼5 × 105 CFU of BCG (week 0), and 11 of them were boosted at week 8 with 109 PFU of AdAg85A. At week 14, all goats were challenged by the endobronchial route with ∼1.5 × 103 CFU of Mycobacterium caprae. The animals were euthanized at week 28. Cellular and humoral immunity induced by vaccination and M. caprae infection was measured throughout the study. After challenge BCG-AdAg85A-vaccinated animals exhibited reduced pathology compared to BCG-vaccinated animals in lungs and in pulmonary lymph nodes. There were significant reductions in bacterial load in both groups of vaccinated goats, but the reduction was more pronounced in prime-boosted animals. Antigen-specific gamma interferon (IFN-γ) and humoral responses were identified as prognostic biomarkers of vaccination outcome depending on their correlation with pathological and bacteriological results. As far as we know, this is the first report using multidetector computed tomography (MDCT) to measure vaccine efficacy against pulmonary TB in an animal model. The use in vaccine trials of animals that are natural hosts of TB may improve research into human TB vaccines. Copyright © 2012, American Society for Microbiology. All Rights Reserved.

Lewis D.J.M.,University of Surrey | Wang Y.,Kings College London | Huo Z.,University of Surrey | Giemza R.,Kings College London | And 5 more authors.
Journal of Virology | Year: 2014

The international effort to prevent HIV-1 infection by vaccination has failed to develop an effective vaccine. The aim of this vaccine trial in women was to administer by the vaginal mucosal route a vaccine consisting of HIV-1 gp140 linked to the chaperone 70-kDa heat shock protein (HSP70). The primary objective was to determine the safety of the vaccine. The secondary objective was to examine HIV-1 infectivity ex vivo and innate and adaptive immunity to HIV-1. Protocol-defined female volunteers were recruited. HIV-1 CN54gp140 linked to HSP70 was administered by the vaginal route. Significant adverse reactions were not detected. HIV-1 was significantly inhibited ex vivo in postimmunization CD4+ T cells compared with preimmunization CD4+ T cells. The innate antiviral restrictive factor APOBEC3G was significantly upregulated, as were CC chemokines which induce downregulation of CCR5 in CD4+ T cells. Indeed, a significant inverse correlation between the proportion of CCR5+ T cells and the concentration of CCL-3 or CCL-5 was found. Importantly, the upregulation of APOBEC3G showed a significant inverse correlation, whereas CCR5 exhibited a trend to correlate with inhibition of HIV-1 infection (r=0.51). Furthermore, specific CD4+ and CD8+ T cell proliferative responses were significantly increased and CD4+ T cells showed a trend to have an inverse correlation with the viral load (r=-0.60). However, HIVgp140-specific IgG or IgA antibodies were not detected. The results provide proof of concept that an innate mechanism consisting of CC chemokines, APOBEC3G, and adaptive immunity by CD4 and CD8 T cells might be involved in controlling HIV-1 infectivity following vaginal mucosal immunization in women. (This study has been registered at ClinicalTrials.gov under registration no. NCT01285141). © 2014, American Society for Microbiology.

Wang Y.,Kings College London | Whittall T.,Kings College London | Rahman D.,Kings College London | Bunnik E.M.,AMC Medical Research | And 7 more authors.
PLoS ONE | Year: 2012

The AID/APOBEC family (activation induced deaminase/apolipoprotein B mRNA editing cytokine deaminase) in B cells play important roles in adaptive and innate immunity. Whereas APOBEC3G has been studied in CD4+ T cells and myeloid cells its functional potential in B cells has received little attention. AID combines two critical functions of antibodies, class switching and affinity maturation and may serve as a functional surrogate of protection. These functions were studied following systemic immunization of rhesus macaques with recombinant HLA constructs, linked with HIV and SIV antigens and HSP70 to dextran. The results showed significant upregulation of AID in CD20+ B cells, APOBEC 3G in CD27+ memory B cells and CD4+ effector memory T cells. After immunization the upregulated APOBEC 3G and AID were directly correlated in B cells (p<0.0001). Following challenge with SHIV SF162.P4 the viral load was inversely correlated with AID in B cells and APOBEC 3G in B and T cells, suggesting that both deaminases may have protective functions. Investigation of major interactions between DC, T cells and B cells showed significant increase in membrane associated IL-15 in DC and CD40L in CD4+ T cells. IL-15 binds the IL-15 receptor complex in CD4+ T and B cells, which may reactivate the DC, T and B cell interactions. The overall results are consistent with AID inhibiting pre-entry SHIV by eliciting IgG and IgA antibodies, whereas APOBEC 3G may contribute to the post-entry control of SHIV replication and cellular spread. © 2012 Wang et al.

Chiappini E.,University of Florence | della Bella C.,University of Florence | Bonsignori F.,University of Florence | Sollai S.,University of Florence | And 7 more authors.
PLoS ONE | Year: 2012

Background: Although currently available IGRA have been reported to be promising markers for TB infection, they cannot distinguish active tuberculosis (TB) from latent infection (LTBI). Objective: Children with LTBI, active TB disease or uninfected were prospectively evaluated by an in-house ELISPOT assay in order to investigate possible immunological markers for a differential diagnosis between LTBI and active TB. Methods: Children at risk for TB infection prospectively enrolled in our infectious disease unit were evaluated by in-house IFN-γ and IL-2 based ELISPOT assays using a panel of Mycobacterium tuberculosis antigens. Results: Twenty-nine children were classified as uninfected, 21 as LTBI and 25 as active TB cases (including 5 definite and 20 probable cases). Significantly higher IFN-γ ELISPOT responses were observed in infected vs. uninfected children for ESAT-6 (p<0.0001), CFP-10 (p<0.0001), TB 10.3 (p = 0.003), and AlaDH (p = 0.001), while differences were not significant considering Ag85B (p = 0.063), PstS1 (p = 0.512), and HspX (16 kDa) (p = 0.139). IL-2 ELISPOT assay responses were different for ESAT-6 (p<0.0001), CFP-10 (p<0.0001), TB 10.3 (p<0.0001), HspX (16 kDa) (p<0.0001), PstS1 (p<0.0001) and AlaDH (p = 0.001); but not for Ag85B (p = 0.063). Comparing results between children with LTBI and those with TB disease differences were significant for IFN-γ ELISPOT only for AlaDH antigen (p = 0.021) and for IL-2 ELISPOT assay for AlaDH (p<0.0001) and TB 10.3 antigen (p = 0.043). ROC analyses demonstrated sensitivity of 100% and specificity of 81% of AlaDH-IL-2 ELISPOT assay in discriminating between latent and active TB using a cut off of 12.5 SCF per million PBMCs. Conclusion: Our data suggest that IL-2 based ELISPOT with AlaDH antigen may be of help in discriminating children with active from those with latent TB. © 2012 Chiappini et al.

Corner L.A.L.,University College Dublin | Costello E.,Central Veterinary Research Laboratory | O'Meara D.,Central Veterinary Research Laboratory | Lesellier S.,University College Dublin | And 6 more authors.
Vaccine | Year: 2010

Eurasian badgers (Meles meles) are a reservoir host of Mycobacterium bovis and are implicated in the transmission of tuberculosis to cattle in Ireland and Great Britain. The development of a vaccine for use in badgers is considered a key element of any long-term sustainable campaign to eradicate the disease from livestock in both countries. The aim of this study was to investigate the protective response of badgers vaccinated orally with Bacille Calmette-Guérin (BCG) encapsulated in a lipid formulation, followed by experimental challenge with M. bovis. A group of badgers was vaccinated by inoculating the BCG-lipid mixture containing approximately 108colony forming units (cfu) of BCG into the oesophagus. The control group was sham inoculated with the lipid formulation only. Thirteen weeks after vaccination all the badgers were challenged with approximately 104cfu of M. bovis delivered by endobronchial inoculation. Blood samples were taken throughout the study and the cell mediated immune (CMI) responses in peripheral blood were monitored by the IFN-γ ELISA and ELISPOT assay. At 17 weeks after infection all the badgers were examined post-mortem to assess the pathological and bacteriological responses to challenge. All badgers in both groups were found to be infected. However, a significant protective effect of BCG vaccination was measured as a decrease in the number and severity of gross lesions, lower bacterial load in the lungs, and fewer sites of infection. The analysis of immune responses showed that vaccination with BCG did not generate any detectable CMI immunological responses, however the levels of the responses increased in both groups following M. bovis infection. The results of the study showed that vaccination with oral BCG in the lipid formulation generated a protective effect in the badgers. © 2010 Elsevier Ltd.

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