کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
6135932 1593642 2011 12 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
The effects of macrophage source on the mechanism of phagocytosis and intracellular survival of Leishmania
موضوعات مرتبط
علوم زیستی و بیوفناوری ایمنی شناسی و میکروب شناسی ایمونولوژی
پیش نمایش صفحه اول مقاله
The effects of macrophage source on the mechanism of phagocytosis and intracellular survival of Leishmania
چکیده انگلیسی

Leishmania spp. protozoa are obligate intracellular parasites that replicate in macrophages during mammalian infection. Efficient phagocytosis and survival in macrophages are important determinants of parasite virulence. Macrophage lines differ dramatically in their ability to sustain intracellular Leishmania infantum chagasi (Lic). We report that the U937 monocytic cell line supported the intracellular replication and cell-to-cell spread of Lic during 72 h after parasite addition, whereas primary human monocyte-derived macrophages (MDMs) did not. Electron microscopy and live cell imaging illustrated that Lic promastigotes anchored to MDMs via their anterior ends and were engulfed through symmetrical pseudopods. In contrast, U937 cells bound Lic in diverse orientations, and extended membrane lamellae to reorient and internalize parasites through coiling phagocytosis. Lic associated tightly with the parasitophorous vacuole (PV) membrane in both cell types. PVs fused with LAMP-1-expressing compartments 24 h after phagocytosis by MDMs, whereas U937 cell PVs remained LAMP-1 negative. The expression of one phagocytic receptor (CR3) was higher in MDMs than U937 cells, leading us to speculate that parasite uptake proceeds through dissimilar pathways between these cells. We hypothesize that the mechanism of phagocytosis differs between primary versus immortalized human macrophage cells, with corresponding differences in the subsequent intracellular fate of the parasite.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Microbes and Infection - Volume 13, Issues 12–13, November 2011, Pages 1033-1044
نویسندگان
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