**1. Introduction**

Kusaka H, Hagiwara K, Kaji R, Kawakami H. Mutations of optineurin in amyotro‐

[64] Sugihara K, Maruyama H, Kamada M, Morino H, Kawakami H. Screening for OPTN mutations in amyotrophic lateral sclerosis in a mainly Caucasian population. Neuro‐

phic lateral sclerosis. Nature 2010; 465:223-6.

biol Aging 2011; 32: 1923.e9-10.

96 Current Advances in Amyotrophic Lateral Sclerosis

Neuroinflammation is an inflammatory response that takes place within the central nervous system (CNS) during a neurodegenerative process or following a neuronal injury. The main effectors of neuroinflammation, which are astrocytes, microglia and immune cells can confer in a context- and time-dependent manner both neuroprotective and neurotoxic effects. It has now become evident that neuroinflammation is a prominent pathological hallmark of several neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease and Amyotro‐ phic Lateral Sclerosis (ALS)(reviewed in [1, 2]). Indeed, reactive astrocytes and microglia as well as infiltrating T lymphocytes have been identified in ALS experimental models and patients. In the present chapter, we will describe the neuroinflammatory phenotype that characterizes ALS and discuss how the aberrant astrocytes, microglia and immune cells may actively participate in the neurodegenerative process. Further, we will examine the therapeutic potential of targeting neuroinflammation in both pre-clinical disease models and ALS patients.
