Phagocytosis of A.fumigatus conidia

We were investigating phagocytosis of Aspergillus fumigatus conidia by primary human neutrophils and monocytes using a novel technique. FITC-labelled conidia were allowed to be phagocytosed and then stained with an APC-labelled anti-FITC antibody to allow for discrimination of cells with internalised conidia (FITC+ APC-) or adherent conidia (FITC+ APC+). This assay was done for different time points using either resting / dormant or pre-swollen conidia.
Conclusion:
Our proposed method to analyze phagocytosis of FITC-labeled conidia by human primary phagocytes and to distinguish internalization and adherence by counterstaining with an anti-FITC antibody is an easy, reliable and flexible way to quantify host-pathogen interaction. Samples with conidia were controlled by samples without conidia (unstimulated). FITC labeled conidia are controlled by unlabeled conidia. CST beads were used to check cytometer performance regularly.