Figure 4

Exclusion of artifacts caused by adherence of RBCs and residual bodies to THP-1 cells. (A) Fluorescence of THP-1 cells fed with np-RBC-fed treated or not with water to lyse adherent intact RBCs. (B) Fluorescence of THP-1 cells fed with p-RBC in presence or absence of residual bodies (RBs). (A, B) CF-SE fluorescence vs side scatter dot plots of THP-1 cells fed with treated or untreated RBCs are very similar excluding artefactual adherence of RBCs or RBs to THP-1 cells. One representative experiment out of four (A) or three (B) with similar results. Data are percentages of phagocytically active THP-1 cells counted above the fluorescence threshold set in each experiment (for details, see Methods).