Publications by authors named "Rosana V Rocha"

A vaccine for bovine tuberculosis is urgently needed. The BCG vaccine (the Bacille Calmette-Guérin), currently the only licensed vaccine for tuberculosis in humans, offers variable protection in cattle. However, BCG is a highly safe vaccine, and any alternative vaccine must not only offer greater protection than BCG but also match and improve its safety profile.

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Article Synopsis
  • * In a trial, 74 heifers were vaccinated with different strains and then exposed to naturally infected animals, but the initial vaccination did not produce an adequate immune response, and re-vaccination did not show significant protection against the disease.
  • * The study found a 23% transmission of wild-style strains in non-vaccinated animals, and while some vaccine candidates showed promise in reducing lesions, overall results indicated that further evaluation is needed, as current vaccines did not ensure improved outcomes.
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Bovine tuberculosis (bTB) represents a threat to livestock production. Mycobacterium bovis is the main causative agent of bTB and a pathogen capable of infecting wildlife and humans. Eradication programs based on surveillance in slaughterhouses with mandatory testing and culling of reactive cattle have failed to eradicate bTB in many regions worldwide.

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Introduction: Granulocyte-macrophage colony stimulating factor (GM-CSF) and interleukin-4 (IL-4) are cytokines widely used in monocyte differentiation experiments, vaccine formulations and disease treatment. The aim of this study was to produce recombinant bovine GM-CSF and IL-4 in an episomal expression system that conserves the postransductional modification of the native proteins and to use the products to differentiate bovine monocytes into dendritic cells.

Material And Methods: The recombinant proteins rGM-CSF and rIL-4 were expressed in PEAKrapid CRL-2828 human kidney cells, ATCC CRL-2828.

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Bovine tuberculosis (bTB) is a disease produced by Mycobacterium bovis that affects livestock, wild animals, and humans. The classical diagnostic method to detect bTB is measuring the response induced with the intradermal injection of purified protein derivative of M. bovis (PPDb).

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In this study, we characterized the role of Rv2617c in the virulence of . Rv2617c is a protein of unknown function unique to complex (MTC) and , this protein interacts with the virulence factor P36 (also named Erp) and KdpF, a protein linked to nitrosative stress. Here, we showed that knockout of the gene in CDC1551 reduced the replication of the pathogen in a mouse model of infection and favored the trafficking of mycobacteria to phagolysosomes.

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Article Synopsis
  • - Mycobacterium bovis, which causes bovine tuberculosis, is genetically different from Mycobacterium tuberculosis, particularly in the PhoPR two-component system that affects its virulence.
  • - Research revealed that deleting the phoP gene in a M. bovis strain weakened its ability to cause phagosomal arrest in bovine immune cells.
  • - The study found that PhoP regulates important proteins related to stress response and biofilm formation, suggesting it plays a key role in helping M. bovis manage its redox balance and survive in hostile environments.
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In this study, a Mycobacterium bovis knockout strain in phoP-phoR and mce2 operons was tested as an antituberculosis experimental vaccine in animal models. The double mutant strain was significantly more attenuated than the wild type strain in inmunocompetent and inmunodeficient mice. Vaccination with the double mutant protected mice against challenge with a virulent M.

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Background: Tuberculosis is one of the leading causes of mortality throughout the world. Mycobacterium tuberculosis, the agent of human tuberculosis, has developed strategies involving proteins and other compounds called virulence factors to subvert human host defences and damage and invade the human host. Among these virulence-related proteins are the Mce proteins, which are encoded in the mce1, mce2, mce3 and mce4 operons of M.

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