Related Experiment Video
Updated: Jun 26, 2025
Macrophage Cholesterol Depletion and Its Effect on the Phagocytosis of Cryptococcus neoformans
Published on: December 19, 2014
Assessing Phagocytosis of Cryptococcus neoformans Cells in Human Monocytes or the J774 Murine Macrophage Cell Line
Emmanuel Lafont1, Aude Sturny-Leclère2, Carolina Coelho3
1Translational Mycology Research Group, Institut Pasteur, Université Paris Cité, National Reference Center for Invasive Mycoses and Antifungals, Mycology Department, Paris, France.
Abstract:
Monocyte/macrophage cells play a central role in innate immunity against C. neoformans and C. gattii, species known to cause human disease. Cryptococcus is the only fungal genus known to possess such a large extracellular polysaccharide capsule, which impacts interactions of innate cells with the yeast. This interaction results in different fates, such as phagocytosis and intracellular proliferation and, as the interaction progresses, vomocytosis, cell-to-cell transfer, lysis of macrophages, or yeast killing. Differentiating internalized versus external Cryptococcus cells is thus essential to evaluate monocyte-macrophage phagocytosis. We describe here a protocol that allows quantification of Cryptococcus spp. phagocytosis using quantitative flow cytometry in human monocytes and a murine macrophage cell line (J774).
Insights
This study presents a new method to quantify Cryptococcus phagocytosis by immune cells. The protocol uses flow cytometry to differentiate between internal and external yeast, aiding innate immunity research.
Area of Science:
- Immunology
- Mycology
- Cell Biology
Background:
- Monocyte/macrophage cells are crucial for innate immunity against fungal pathogens like Cryptococcus neoformans and Cryptococcus gattii.
- The large polysaccharide capsule of Cryptococcus influences interactions with innate immune cells, leading to varied outcomes including phagocytosis, intracellular proliferation, and macrophage lysis.
- Distinguishing between internalized and external Cryptococcus cells is critical for accurately assessing phagocytosis by monocytes and macrophages.
Purpose of the Study:
- To develop and describe a reliable protocol for quantifying Cryptococcus spp. phagocytosis.
- To enable accurate assessment of monocyte-macrophage interactions with Cryptococcus, differentiating internalized from external yeast cells.
Main Methods:
- Quantitative flow cytometry protocol.
- Utilizes human monocytes and the murine macrophage cell line J774.
- Differentiates internalized versus external Cryptococcus cells.
Main Results:
- A protocol for quantifying Cryptococcus spp. phagocytosis was successfully established.
- The method allows for the differentiation of internalized versus external Cryptococcus cells.
- The protocol is applicable to both human monocytes and a murine macrophage cell line.
Conclusions:
- The described quantitative flow cytometry protocol provides an essential tool for studying Cryptococcus-host interactions.
- Accurate quantification of phagocytosis is vital for understanding innate immunity against Cryptococcus fungal infections.
- This method facilitates research into the complex interplay between macrophages and Cryptococcus yeasts.
