PMID- 25189678 OWN - NLM STAT- MEDLINE DCOM- 20150622 LR - 20141004 IS - 0035-3787 (Print) IS - 0035-3787 (Linking) VI - 170 IP - 10 DP - 2014 Oct TI - Immune system's role in viral encephalitis. PG - 577-83 LID - S0035-3787(14)00905-9 [pii] LID - 10.1016/j.neurol.2014.07.005 [doi] AB - Viral infections can be a major thread for the central nervous system (CNS), therefore, the immune system must be able to mount a highly proportionate immune response, not too weak, which would allow the virus to proliferate, but not too strong either, to avoid collateral damages. Here, we aim at reviewing the immunological mechanisms involved in the host defense in viral CNS infections. First, we review the specificities of the innate as well as the adaptive immune responses in the CNS, using several examples of various viral encephalitis. Then, we focus on three different modes of interactions between viruses and immune responses, namely human Herpes virus-1 encephalitis with the defect in innate immune response which favors this disease; JC virus-caused progressive multifocal leukoencephalopathy and the crucial role of adaptive immune response in this example; and finally, HIV infection with the accompanying low grade chronic inflammation in the CNS in some patients, which may be an explanation for the presence of cognitive disorders, even in some well-treated HIV-infected patients. We also emphasize that, although the immune response is generally associated with viral replication control and limited cellular death, an exaggerated inflammatory reaction can lead to tissue damage and can be detrimental for the host, a feature of the immune reconstitution inflammatory syndrome (IRIS). We will briefly address the indication of steroids in this situation. CI - Copyright (c) 2014 Elsevier Masson SAS. All rights reserved. FAU - Spatola, M AU - Spatola M AD - Service of Neurology, BH.10.131, Bugnon 44, 1010 Lausanne, Switzerland. FAU - Du Pasquier, R A AU - Du Pasquier RA AD - Service of Neurology, BH.10.131, Bugnon 44, 1010 Lausanne, Switzerland; Laboratory of neuro-immunology, Centre of clinical neurosciences, Department of Clinical Neurosciences, University Hospital of Lausanne (CHUV), rue du Bugnon 46, 1011 Lausanne, Switzerland. Electronic address: Renaud.Du-Pasquier@chuv.ch. LA - eng PT - Journal Article DEP - 20140902 PL - France TA - Rev Neurol (Paris) JT - Revue neurologique JID - 2984779R SB - IM MH - Central Nervous System/immunology MH - Encephalitis, Viral/*immunology MH - Humans MH - Immune System/*immunology MH - Immunity, Innate OTO - NOTNLM OT - Central nervous system OT - Encephalite herpetique a HSV-1 OT - HIV OT - HSV-1 encephalitis OT - Immune surveillance OT - Leucoencephalopathie multifocale progressive OT - Progressive multifocal leukoencephalopathy OT - Surveillance immunitaire OT - Systeme nerveux central OT - VIH EDAT- 2014/09/06 06:00 MHDA- 2015/06/24 06:00 CRDT- 2014/09/06 06:00 PHST- 2014/07/07 00:00 [received] PHST- 2014/07/25 00:00 [accepted] PHST- 2014/09/06 06:00 [entrez] PHST- 2014/09/06 06:00 [pubmed] PHST- 2015/06/24 06:00 [medline] AID - S0035-3787(14)00905-9 [pii] AID - 10.1016/j.neurol.2014.07.005 [doi] PST - ppublish SO - Rev Neurol (Paris). 2014 Oct;170(10):577-83. doi: 10.1016/j.neurol.2014.07.005. Epub 2014 Sep 2.