Journal of Clinical Immunology

, Volume 25, Issue 4, pp 365–375

Non-Pathogenic Mycobacterium smegmatis Induces the Differentiation of Human Monocytes Directly into Fully Mature Dendritic Cells

  • Angelo Martino
  • Alessandra Sacchi
  • Elisabetta Volpe
  • Chiara Agrati
  • Rafaella De Santis
  • Leopoldo Paolo Pucillo
  • Vittorio Colizzi
  • Silvia Vendetti
Article

DOI: 10.1007/s10875-005-4188-x

Cite this article as:
Martino, A., Sacchi, A., Volpe, E. et al. J Clin Immunol (2005) 25: 365. doi:10.1007/s10875-005-4188-x

Abstract

Mycobacterium smegmatis infects human monocytes that can be precursors of dendritic cells. We tested whether the interaction of M. smegmatis with monocytes modulated their differentiation into dendritic cells. We found that M. smegmatis-infected monocytes differentiated into CD1aCCR7+ dendritic cells in the presence of GM-CSF and IL-4 and acquired a mature phenotype since they expressed CD83 molecules in the absence of maturation stimuli. Dendritic cells derived from M. smegmatis-infected monocytes stimulated with bacterial products, produced IL-10 and still retained the capacity to produce IL-12. Consequently, they polarized naïve T lymphocytes towards a mixed Th1/Th2 immune response inducing both IFN-γ and IL-4 production. These findings suggest that the exposure to environmental mycobacteria could modulate the differentiation of dendritic cells making them able to migrate into secondary lymphoid organs and modulate the adaptive immune response. This could explain one of the mechanisms by which environmental mycobacteria can influence the immune response to pathogenic species.

Key Words

M. smegmatisdendritic cellsmonocyte differentiationCD1a

Copyright information

© Springer Science + Business Media, Inc. 2005

Authors and Affiliations

  • Angelo Martino
    • 1
  • Alessandra Sacchi
    • 1
  • Elisabetta Volpe
    • 2
  • Chiara Agrati
    • 1
  • Rafaella De Santis
    • 1
  • Leopoldo Paolo Pucillo
    • 1
  • Vittorio Colizzi
    • 4
  • Silvia Vendetti
    • 1
    • 3
    • 5
  1. 1.National Institute for Infectious Diseases “Lazzaro Spallanzani,”RomeItaly
  2. 2.Institute of Neurobiology and Molecular MedicineNational Research CouncilRomeItaly
  3. 3.Department of InfectiousParasitic and Immune-Mediated Diseases, Istituto Superiore di SanitàRomeItaly
  4. 4.Department of BiologyUniversity of Tor VergataRomeItaly
  5. 5.Department of InfectiousParasitic and Immune-Mediated Diseases, Istituto Superiore di SanitàRomeItaly