Fig. 2. F-actin accumulation around parasites during or following phagocytosis. (A) Macrophages untreated () or treated with IFN- (, [UNK]) were infected with L. amazonensis metacyclic promastigotes (, ) or amastigotes ([UNK]) and then fixed and permeabilized at the different time points indicated. F-actin was stained with Alexa Fluor 488 phalloidin (green staining) and parasites with a mouse anti-Leishmania immune serum and a Texas Red conjugate (red staining) before examination of the cells by fluorescence microscopy. The percentages of promastigotes or amastigotes surrounded by F-actin were determined after counting about 100 parasites for each time point. Data are the means±s.d. of three experiments () or are from a single experiment (,[UNK]). (B,C) Fluorescence confocal microscopy of macrophages incubated for 10 minutes with L. amazonensis metacyclic promastigotes (B) or amastigotes (C). F-actin and parasites were stained as in A. A 3D reconstruction and an optical section (0.5 µm thickness) are shown in B and C, respectively. Bar, 2 µm.