Microglia at center stage: a comprehensive review about the versatile and unique residential macrophages of the central nervous system

Abstract

// Nils Lannes 1 , Elisabeth Eppler 2 , Samar Etemad 3 , Peter Yotovski 1 and Luis Filgueira 1 1 Albert Gockel, Anatomy, Department of Medicine, University of Fribourg, CH-1700 Fribourg, Switzerland 2 Pestalozzistrasse Zo, Department of BioMedicine, University of Basel, CH-4056 Basel, Switzerland 3 Building 71/218 RBWH Herston, Centre for Clinical Research, The University of Queensland, QLD 4029 Brisbane, Australia Correspondence to: Luis Filgueira, email: luis.filgueira@unifr.ch Keywords: microglia; neuroinflammation; neurodegeneration; virus infection; brain cancer Received: August 23, 2017      Accepted: November 15, 2017      Published: December 11, 2017 ABSTRACT Microglia cells are the unique residential macrophages of the central nervous system (CNS). They have a special origin, as they derive from the embryonic yolk sac and enter the developing CNS at a very early stage. They play an important role during CNS development and adult homeostasis. They have a major contribution to adult neurogenesis and neuroinflammation. Thus, they participate in the pathogenesis of neurodegenerative diseases and contribute to aging. They play an important role in sustaining and breaking the blood-brain barrier. As innate immune cells, they contribute substantially to the immune response against infectious agents affecting the CNS. They play also a major role in the growth of tumours of the CNS. Microglia are consequently the key cell population linking the nervous and the immune system. This review covers all different aspects of microglia biology and pathology in a comprehensive way.