The outcome of phagocytic cell division with infectious cargo depends on single phagosome formation

PLoS One. 2008 Sep 16;3(9):e3219. doi: 10.1371/journal.pone.0003219.


Given that macrophages can proliferate and that certain microbes survive inside phagocytic cells, the question arises as to the post-mitotic distribution of microbial cargo. Using macrophage-like cells we evaluated the post-mitotic distribution of intracellular Cryptococcus yeasts and polystyrene beads by comparing experimental data to a stochastic model. For beads, the post-mitotic distribution was that expected from chance alone. However, for yeast cells the post-mitotic distribution was unequal, implying preferential sorting to one daughter cell. This mechanism for unequal distribution was phagosomal fusion, which effectively reduced the intracellular particle number. Hence, post-mitotic intracellular particle distribution is stochastic, unless microbial and/or host factors promote unequal distribution into daughter cells. In our system unequal cargo distribution appeared to benefit the microbe by promoting host cell exocytosis. Post-mitotic infectious cargo distribution is a new parameter to consider in the study of intracellular pathogens since it could potentially define the outcome of phagocytic-microbial interactions.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Cell Line
  • Cell Proliferation
  • Cryptococcus neoformans / immunology
  • Exocytosis
  • Macrophages / metabolism
  • Macrophages / microbiology*
  • Mice
  • Mitosis
  • Models, Biological
  • Models, Theoretical
  • Phagocytes / immunology*
  • Phagocytosis / immunology*
  • Phagosomes / immunology*
  • Species Specificity
  • Stochastic Processes