{"id":1144,"date":"2016-11-10T12:36:02","date_gmt":"2016-11-10T12:36:02","guid":{"rendered":"http:\/\/www.virologyhighlights.com\/?p=1144"},"modified":"2018-05-25T08:31:46","modified_gmt":"2018-05-25T08:31:46","slug":"neurotropic-infections-are-not-just-about-the-cns","status":"publish","type":"post","link":"https:\/\/www.elsevierblogs.com\/virology\/neurotropic-infections-are-not-just-about-the-cns\/","title":{"rendered":"Neurotropic infections are not just about the CNS"},"content":{"rendered":"<p><a href=\"http:\/\/www.sciencedirect.com\/science\/article\/pii\/S0042682216302653\" target=\"_blank\">Read the full article on ScienceDirect.<\/a><\/p>\n<h2>CD4+ T Cells Require Either B Cells or CD8+ T Cells to Control Spread and Pathogenesis of a Neurotropic Infection<\/h2>\n<p><em>Text by Andreas C. Solomos, Kevin J. O\u2019Regan, and Glenn F. Rall<\/em><\/p>\n<p>Research highlights the old notion of the \u201cimmune privileged\u201d central nervous system (CNS) is rapidly being revised as evidence accumulates that the immune system is, in fact, critical for homeostatic CNS surveillance as well direct resolution of neurotropic infections.\u00a0 Our lab has long used a mouse model in which only CNS neurons are permissive for measles virus (MV) infection, allowing us to directly assess immune-neuron interactions. In this model, neurons of adult, immune competent mice do become infected, but infected animals show no signs of illness because the anti-viral response is rapid and effective.\u00a0 In contrast, mice that lack adaptive immune cells, T and B lymphocytes, die of unrestricted MV infection by 3 weeks post-challenge.\u00a0 In this study, we further dissected the roles of the adaptive response, using available immunodeficient mice lacking one or more components of the adaptive response, and\/or treated infected mice with antibodies to remove specific immune cell populations. We discovered that mice lacking either B cells or CD8<sup>+<\/sup> cytotoxic T cells could survive infection, but were less able to control MV replication compared to immunocompetent mice.\u00a0 In contrast, depletion of CD4<sup>+<\/sup> T cells resulted in illness and death in all mice, but required either B cells or CD8<sup>+<\/sup> T cells, implicating a coordinated interplay of adaptive immune cells in resolution of a CNS-restricted infection.<\/p>\n<p>One surprising aspect of this study was that B cells complement CD4<sup>+<\/sup> T cells despite virtually no evidence of these cells in the parenchyma over the course of infection.\u00a0 This suggests that whatever contribution B cells make to clearance occurs in the periphery, perhaps influencing CD4<sup>+<\/sup> T cells that then migrate to the CNS, or via the production of antiviral antibodies that can percolate into the MV-infected brain.\u00a0 This observation was the moment we knew we had a compelling story, adding to a growing literature that shows that the periphery plays an important role in shaping CNS immune responses: put simply, neurotropic infections are not just about the CNS.\u00a0 Additionally, our data implied that viral RNA persists in the brain following infection of immune competent mice, despite the lack of illness or disease.\u00a0 Thus, the presence of persisting viral RNA in neurons and neuropathology are uncoupled, implicating that some mechanism of viral control must exist in immune competent mice to limit unrestricted viral replication and spread.\u00a0 Together, we believe these studies underscore an emerging principle in neuroimmunology: \u00a0immune responses to neurotropic pathogens are functionally distinct from those that infect the periphery; such differences result in unique pathogenic outcomes, despite using common cellular players and soluble mediators.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-1149\" src=\"http:\/\/www.elsevierblogs.com\/virology\/wp-content\/uploads\/Figure-2.jpg\" alt=\"figure\" width=\"346\" height=\"222\" \/><\/p>\n<h3>Figure legend<\/h3>\n<p>Article figure 5B: <strong>Role of CD4+T cells in survival and viral control.<\/strong> NSE-CD46+ (n=21), NSE-CD46+\/RAG-2 KO (n=28), NSE-CD46+\/MHC-II KO (n=40) or NSE-CD46+ mice injected with CD4-depleting antibody (n=8) or an isotype control (n=5) were challenged IC with 1\u00d7104 PFU of MV-Ed and monitored daily for survival.<\/p>\n<h3>Introducing the authors<\/h3>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-1148\" src=\"http:\/\/www.elsevierblogs.com\/virology\/wp-content\/uploads\/Authors-2.jpg\" alt=\"authors\" width=\"4160\" height=\"2340\" srcset=\"https:\/\/www.elsevierblogs.com\/virology\/wp-content\/uploads\/Authors-2.jpg 4160w, https:\/\/www.elsevierblogs.com\/virology\/wp-content\/uploads\/Authors-2-300x169.jpg 300w, https:\/\/www.elsevierblogs.com\/virology\/wp-content\/uploads\/Authors-2-1024x576.jpg 1024w\" sizes=\"auto, (max-width: 4160px) 100vw, 4160px\" \/><\/p>\n<p>Pictured from left to right the Rall Lab: \u00a0Alicia Holmgren, Amanda Purdy, Andreas Solomos, Glenn Rall, Sarah Cavanaugh, Kevin O\u2019Regan, and Christine Matullo<\/p>\n<h3>About the research<\/h3>\n<p><em><a href=\"http:\/\/www.sciencedirect.com\/science\/article\/pii\/S0042682216302653\" target=\"_blank\">CD4+ T cells require either B cells or CD8+ T cells to control spread and pathogenesis of a neurotropic infection<\/a><\/em><br \/>\nAndreas C. Solomos, Kevin J. O\u2019Regan, Glenn F. Rall<br \/>\n<em>Virology<\/em>, Volume 499, December 2016, Pages 196\u2013202<\/p>\n<!-- AddThis Advanced Settings generic via filter on the_content --><!-- AddThis Share Buttons generic via filter on the_content -->","protected":false},"excerpt":{"rendered":"<p>Read the full article on ScienceDirect. CD4+ T Cells Require Either B Cells or CD8+ T Cells to Control Spread and Pathogenesis of a Neurotropic Infection Text by Andreas C. Solomos, Kevin J. O\u2019Regan, and Glenn F. Rall Research highlights the old notion of the \u201cimmune privileged\u201d central nervous system (CNS) is rapidly being revised <a class=\"read-more\" href=\"https:\/\/www.elsevierblogs.com\/virology\/neurotropic-infections-are-not-just-about-the-cns\/\">Read More&#8230;<\/a><!-- AddThis Advanced Settings generic via filter on get_the_excerpt --><!-- AddThis Share Buttons generic via filter on get_the_excerpt --><\/p>\n","protected":false},"author":1,"featured_media":1149,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[5,632],"tags":[896,888,883,889,892,427,887,885,898,897,893,497,895,894,890,891,886,884],"class_list":["post-1144","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-highlighted-article","category-immunity-to-viruses","tag-andreas-c-solomos","tag-b-cells","tag-b-lymphocytes","tag-cd4-t-cells","tag-cd8-t-cells","tag-central-nervous-system","tag-cns","tag-cytotoxic","tag-glenn-f-rall","tag-kevin-j-oregan","tag-mouse","tag-mouse-model","tag-mv-infection","tag-mv-replication","tag-neuroimmunology","tag-neurotropic","tag-t-cells","tag-t-lymphocytes"],"_links":{"self":[{"href":"https:\/\/www.elsevierblogs.com\/virology\/wp-json\/wp\/v2\/posts\/1144","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.elsevierblogs.com\/virology\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.elsevierblogs.com\/virology\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.elsevierblogs.com\/virology\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.elsevierblogs.com\/virology\/wp-json\/wp\/v2\/comments?post=1144"}],"version-history":[{"count":3,"href":"https:\/\/www.elsevierblogs.com\/virology\/wp-json\/wp\/v2\/posts\/1144\/revisions"}],"predecessor-version":[{"id":1150,"href":"https:\/\/www.elsevierblogs.com\/virology\/wp-json\/wp\/v2\/posts\/1144\/revisions\/1150"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.elsevierblogs.com\/virology\/wp-json\/wp\/v2\/media\/1149"}],"wp:attachment":[{"href":"https:\/\/www.elsevierblogs.com\/virology\/wp-json\/wp\/v2\/media?parent=1144"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.elsevierblogs.com\/virology\/wp-json\/wp\/v2\/categories?post=1144"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.elsevierblogs.com\/virology\/wp-json\/wp\/v2\/tags?post=1144"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}