Christel Claes1, Johanna Van Den Daele1, Ruben Boon2, Sarah Schouteden2, Alessio Colombo3, Laura Sebastian Monasor3, Mark Fiers4, Laura Ordovás2, FatemehArefeh Nami2, Bernd Bohrmann5, Sabina Tahirovic3, Bart De Strooper4, Catherine M Verfaillie6. 1. Department of Development and Regeneration, Stem Cell Biology and Embryology, KU Leuven Stem Cell Institute, Leuven, Belgium; Laboratory for the Research of Neurodegenerative Diseases, VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium. 2. Department of Development and Regeneration, Stem Cell Biology and Embryology, KU Leuven Stem Cell Institute, Leuven, Belgium. 3. German Center for Neurodegenerative Diseases (DZNE), Munich, Germany. 4. Laboratory for the Research of Neurodegenerative Diseases, VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium. 5. Roche Pharmaceutical Research and Early Development NORD Discovery & Translational Area, Roche Innovation Center Basel, Basel, Switzerland. 6. Department of Development and Regeneration, Stem Cell Biology and Embryology, KU Leuven Stem Cell Institute, Leuven, Belgium. Electronic address: catherine.verfaillie@kuleuven.be.
Abstract
INTRODUCTION: Murine microglia expressing the Alzheimer's disease-linked TREM2R47H mutation display variable decrease in phagocytosis, while impaired phagocytosis is reported following loss of TREM2. However, no data exist on TREM2+/R47H human microglia. Therefore, we created human pluripotent stem cell (hPSC) monocytes and transdifferentiated microglia-like cells (tMGs) to examine the effect of the TREM2+/R47H mutation and loss of TREM2 on phagocytosis. METHODS: We generated isogenic TREM2+/R47H, TREM2+/-, and TREM2-/- hPSCs using CRISPR/Cas9. Following differentiation to monocytes and tMGs, we studied the uptake of Escherichia coli fragments and analyzed amyloid plaque clearance from cryosections of APP/PS1+/- mouse brains. RESULTS: We demonstrated that tMGs resemble cultured human microglia. TREM2+/- and TREM2-/- hPSC monocytes and tMGs phagocytosed significantly less E. coli fragments and cleared less amyloid plaques than wild-type hPSC progeny, with no difference for TREM2+/R47H progeny. DISCUSSION: In vitro phagocytosis of hPSC monocytes and tMGs was not affected by the TREM2+/R47H mutation but was significantly impaired in TREM2+/- and TREM2-/- progeny.
INTRODUCTION:Murine microglia expressing the Alzheimer's disease-linked TREM2R47H mutation display variable decrease in phagocytosis, while impaired phagocytosis is reported following loss of TREM2. However, no data exist on TREM2+/R47Hhuman microglia. Therefore, we created human pluripotent stem cell (hPSC) monocytes and transdifferentiated microglia-like cells (tMGs) to examine the effect of the TREM2+/R47H mutation and loss of TREM2 on phagocytosis. METHODS: We generated isogenic TREM2+/R47H, TREM2+/-, and TREM2-/- hPSCs using CRISPR/Cas9. Following differentiation to monocytes and tMGs, we studied the uptake of Escherichia coli fragments and analyzed amyloid plaque clearance from cryosections of APP/PS1+/- mouse brains. RESULTS: We demonstrated that tMGs resemble cultured human microglia. TREM2+/- and TREM2-/- hPSC monocytes and tMGs phagocytosed significantly less E. coli fragments and cleared less amyloid plaques than wild-type hPSC progeny, with no difference for TREM2+/R47H progeny. DISCUSSION: In vitro phagocytosis of hPSC monocytes and tMGs was not affected by the TREM2+/R47H mutation but was significantly impaired in TREM2+/- and TREM2-/- progeny.
Authors: Soraia Martins; Andreas Müller-Schiffmann; Lars Erichsen; Martina Bohndorf; Wasco Wruck; Kristel Sleegers; Christine Van Broeckhoven; Carsten Korth; James Adjaye Journal: Int J Mol Sci Date: 2020-06-25 Impact factor: 5.923