MicroRNA-155 knockout mice are susceptible to Mycobacterium tuberculosis infection

Tuberculosis (Edinb). 2015 May;95(3):246-50. doi: 10.1016/j.tube.2015.03.006. Epub 2015 Mar 21.


MicroRNAs (miRNAs) are short, conserved, non-coding RNA molecules that repress translation, followed by the decay of miRNA-targeted mRNAs that encode molecules involved in cell differentiation, development, immunity and apoptosis. At least six miRNAs, including microRNA-155 (miR-155), were up-regulated when born marrow-derived macrophages from C57BL/6 mice were infected with Mycobacterium tuberculosis Erdman. C57BL/6 mice intravenously infected with Erdman showed up-regulation of miR-155 in livers and lungs. Following infection, miR-155-deficient C57BL/6 mice died significantly earlier and had significantly higher numbers of CFU in lungs than wild-type mice. Moreover, fewer CD4(+) T cells, but higher numbers of monocytes and neutrophils, were present in the lungs of Erdman-infected miR-155 knockout (miR-155(-/-)) than of wild-type mice. These findings indicated that miR-155 plays a critical role in immune responses to M. tuberculosis.

Keywords: Mycobacterium tuberculosis; miR-155; microRNA.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • CD4-Positive T-Lymphocytes / immunology
  • CD4-Positive T-Lymphocytes / microbiology
  • Cytokines / blood
  • Disease Models, Animal
  • Genetic Predisposition to Disease
  • Liver / metabolism
  • Lung / immunology
  • Lung / metabolism
  • Lung / microbiology*
  • Male
  • Mice, Inbred C57BL
  • Mice, Knockout
  • MicroRNAs / genetics*
  • MicroRNAs / metabolism
  • Monocytes / immunology
  • Monocytes / microbiology
  • Mycobacterium tuberculosis / immunology
  • Mycobacterium tuberculosis / pathogenicity*
  • Neutrophils / immunology
  • Neutrophils / microbiology
  • Phenotype
  • Time Factors
  • Tuberculosis, Pulmonary / blood
  • Tuberculosis, Pulmonary / genetics*
  • Tuberculosis, Pulmonary / immunology
  • Tuberculosis, Pulmonary / microbiology*


  • Cytokines
  • MicroRNAs
  • Mirn155 microRNA, mouse