{"paper_id":"21a1dc57-2dd3-4d2c-afb4-cd1ffeba7d88","body_text":"Foxp3+ Regulatory T Cells Restrain Th1 Response Shielding the Brain from Lethal Inflammatory Damage during Cryptococcal Meningoencephalitis | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Foxp3 + Regulatory T Cells Restrain Th1 Response Shielding the Brain from Lethal Inflammatory Damage during Cryptococcal Meningoencephalitis Michal Olszewski, Hailong Li, Rylan Hissong, Kristie Goughenour, and 10 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7142999/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted You are reading this latest preprint version Abstract Inflammatory brain damage is an important factor contributing to mortality or lasting neurological sequelae in CNS infections, such as cryptococcal meningoencephalitis (CM), but little is known about natural immunoregulatory mechanisms in the infected brain. Here we report that regulatory T cells (Tregs) are a central immunoregulatory component in CM. Tregs are present within the CNS in both human CM patients and in the experimental murine CM. Treg-depletion exacerbates Th1-driven brain inflammation and neurological symptoms, accelerating mortality, despite enhanced fungal clearance in mouse CM. Aligned brain NanoString, scRNA-seq, and flow cytometry analyses revealed that Tregs reduce brain inflammation, especially T-cell recruitment activation and differentiation, shielding the brain from neurological damage. The major CNS-Treg recruitment appears to be chemokine receptor CCR8-mediated, supporting the importance of the CCR8/CCL1 axis in Treg recruitment into the brain. Tregs in CM are major producers of anti-inflammatory IL-10 and the growth factor Amphiregulin (Areg), which is implicated in neuronal repair. IL-10 deletion in murine CM phenocopies Treg depletion. Areg deletion showed no survival effect; however, IFN-γ production by effector T cells in the brain was reduced, supporting Aregs as a potential internal regulator of Treg immunosuppressive function. Finally, a Treg-enhancing immunotherapy using low dose IL-2-immune complex treatment substantially improves mouse survival and neurological outcomes. Together, we identified that Tregs are crucial for neuronal protection in CM, predominantly via IL-10 production, the CCR8-CCL1 axis is an important CNS-Treg recruitment mechanism and Treg enhancement is a potential therapeutic strategy to mitigate immunopathology during CM, and possibly other forms of meningitis. Biological sciences/Microbiology/Fungi/Fungal host response Health sciences/Pathogenesis/Infection Health sciences/Diseases/Infectious diseases/Fungal infection Full Text Additional Declarations There is NO Competing Interest. Supplementary Files ExtendeddatatableNanoStringandSinglecellanalyses.xlsx Extended data table Cite Share Download PDF Status: Under Review Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {\"props\":{\"pageProps\":{\"initialData\":{\"identity\":\"rs-7142999\",\"acceptedTermsAndConditions\":true,\"allowDirectSubmit\":false,\"archivedVersions\":[],\"articleType\":\"Article\",\"associatedPublications\":[],\"authors\":[{\"id\":491215881,\"identity\":\"a7e4afcd-cd84-417c-a1a7-844c973f0586\",\"order_by\":0,\"name\":\"Michal Olszewski\",\"email\":\"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAw0lEQVRIiWNgGAWjYDACdijND8QHGBtAJCEtzFBasoFkLQYglURp4Wdmf/zhY1tdtPGN7MQDP3cwyPHdSMCvRbKZx8BwZtvh3G03cjcc7D3DYCxJSIvBYR6GZN5tB8BaDjO2MSRuIKyF/cHhv9vqcjfPgGipJ0ILg2Ez4zbm3A0SEC0JBkT4xZix99/h3Bln3gL90iZhOPPMA/xa+NnbH3/4caYut789d/OHn2028nzHCdiCDiRIUz4KRsEoGAWjADsAAKgkTYGCALDeAAAAAElFTkSuQmCC\",\"orcid\":\"\",\"institution\":\"University of Michigan Health System,\",\"correspondingAuthor\":true,\"prefix\":\"\",\"firstName\":\"Michal\",\"middleName\":\"\",\"lastName\":\"Olszewski\",\"suffix\":\"\"},{\"id\":491215882,\"identity\":\"e5f500b0-d3ea-4054-8324-edf59d99d58f\",\"order_by\":1,\"name\":\"Hailong Li\",\"email\":\"\",\"orcid\":\"https://orcid.org/0000-0003-0292-6774\",\"institution\":\"NHC Key Laboratory of AIDS Immunology, National Clinical Research Center for Laboratory Medicine, The First Affiliated Hospital of China Medical University, Shenyang, China, 1100010\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Hailong\",\"middleName\":\"\",\"lastName\":\"Li\",\"suffix\":\"\"},{\"id\":491215883,\"identity\":\"4dd65fdf-0000-4cbf-931f-25381b4c0edb\",\"order_by\":2,\"name\":\"Rylan Hissong\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"University of Michigan Health System\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Rylan\",\"middleName\":\"\",\"lastName\":\"Hissong\",\"suffix\":\"\"},{\"id\":491215884,\"identity\":\"0e941f8b-1f1d-41be-9d75-f42af19636dd\",\"order_by\":3,\"name\":\"Kristie Goughenour\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"University of Michigan Health System\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Kristie\",\"middleName\":\"\",\"lastName\":\"Goughenour\",\"suffix\":\"\"},{\"id\":491215885,\"identity\":\"5f2ec5f5-a234-4413-b4e5-732a56fb55f3\",\"order_by\":4,\"name\":\"Yekateryna Sinitsyna\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"University of Michigan Health System\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Yekateryna\",\"middleName\":\"\",\"lastName\":\"Sinitsyna\",\"suffix\":\"\"},{\"id\":491215886,\"identity\":\"1bc2c301-6070-4699-858a-19d1b7e64971\",\"order_by\":5,\"name\":\"Maia Lintner\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"University of Michigan Health System\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Maia\",\"middleName\":\"\",\"lastName\":\"Lintner\",\"suffix\":\"\"},{\"id\":491215887,\"identity\":\"ea3d3151-7621-4112-8048-ee2277c71ccd\",\"order_by\":6,\"name\":\"Brian Song\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"University of Michigan Health System\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Brian\",\"middleName\":\"\",\"lastName\":\"Song\",\"suffix\":\"\"},{\"id\":491215888,\"identity\":\"c9add765-3ee6-492f-8347-f758f18d4599\",\"order_by\":7,\"name\":\"Heineken Queen\",\"email\":\"\",\"orcid\":\"https://orcid.org/0000-0002-3669-1144\",\"institution\":\"University of Michigan Health System,\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Heineken\",\"middleName\":\"\",\"lastName\":\"Queen\",\"suffix\":\"\"},{\"id\":491215889,\"identity\":\"21798d2c-4ffa-4a7d-bd01-0b221a0b43cf\",\"order_by\":8,\"name\":\"Clifford Cho\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Department of Veterans Affairs Health System\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Clifford\",\"middleName\":\"\",\"lastName\":\"Cho\",\"suffix\":\"\"},{\"id\":491215890,\"identity\":\"941f8be2-ffc6-41fa-81d4-85b092028ffe\",\"order_by\":9,\"name\":\"Anutosh Ganguly\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Department of Veterans Affairs Health System\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Anutosh\",\"middleName\":\"\",\"lastName\":\"Ganguly\",\"suffix\":\"\"},{\"id\":491215891,\"identity\":\"0ee55286-1310-459e-832e-d75228088369\",\"order_by\":10,\"name\":\"Grace Chen\",\"email\":\"\",\"orcid\":\"https://orcid.org/0000-0001-6434-8696\",\"institution\":\"University of Michigan–Ann Arbor\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Grace\",\"middleName\":\"\",\"lastName\":\"Chen\",\"suffix\":\"\"},{\"id\":491215892,\"identity\":\"f3f8b005-3aa7-4ae6-89ed-62b8bcf0b378\",\"order_by\":11,\"name\":\"Jessica Hargarten\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Rutgers New Jersey Medical School\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Jessica\",\"middleName\":\"\",\"lastName\":\"Hargarten\",\"suffix\":\"\"},{\"id\":491215893,\"identity\":\"0d9add04-48d7-4188-a8fc-a6317f64674c\",\"order_by\":12,\"name\":\"Peter Richard Williamson\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"NIH\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Peter\",\"middleName\":\"Richard\",\"lastName\":\"Williamson\",\"suffix\":\"\"},{\"id\":491215894,\"identity\":\"1fb55ff7-9e36-499f-ac6f-804966d7311c\",\"order_by\":13,\"name\":\"Jintao Xu\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"University of Michigan Health System\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Jintao\",\"middleName\":\"\",\"lastName\":\"Xu\",\"suffix\":\"\"}],\"badges\":[],\"createdAt\":\"2025-07-16 19:40:31\",\"currentVersionCode\":1,\"declarations\":\"\",\"doi\":\"10.21203/rs.3.rs-7142999/v1\",\"doiUrl\":\"https://doi.org/10.21203/rs.3.rs-7142999/v1\",\"draftVersion\":[],\"editorialEvents\":[],\"editorialNote\":\"\",\"failedWorkflow\":false,\"files\":[{\"id\":87915405,\"identity\":\"bcd535b9-559a-4ca3-bae3-1396e1c4acfd\",\"added_by\":\"auto\",\"created_at\":\"2025-07-30 10:48:54\",\"extension\":\"pdf\",\"order_by\":1,\"title\":\"\",\"display\":\"\",\"copyAsset\":false,\"role\":\"manuscript-pdf\",\"size\":4560756,\"visible\":true,\"origin\":\"\",\"legend\":\"Article File\",\"description\":\"\",\"filename\":\"Manuscript.pdf\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-7142999/v1_covered_8a20d0b3-b9f1-40a8-a1d3-9b3a9ff6fe06.pdf\"},{\"id\":87914932,\"identity\":\"99c08fca-d8dd-4aa2-abb0-d2a87cf92908\",\"added_by\":\"auto\",\"created_at\":\"2025-07-30 10:40:49\",\"extension\":\"xlsx\",\"order_by\":1,\"title\":\"\",\"display\":\"\",\"copyAsset\":false,\"role\":\"supplement\",\"size\":703624,\"visible\":true,\"origin\":\"\",\"legend\":\"Extended data table\",\"description\":\"\",\"filename\":\"ExtendeddatatableNanoStringandSinglecellanalyses.xlsx\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-7142999/v1/0dcb1f3bf4281a9427e0463b.xlsx\"}],\"financialInterests\":\"There is \\u003cb\\u003eNO\\u003c/b\\u003e Competing Interest.\",\"formattedTitle\":\"\\u003cp\\u003eFoxp3\\u003csup\\u003e+\\u003c/sup\\u003e Regulatory T Cells Restrain Th1 Response Shielding the Brain from Lethal Inflammatory Damage during Cryptococcal Meningoencephalitis\\u003c/p\\u003e\",\"fulltext\":[],\"fulltextSource\":\"\",\"fullText\":\"\",\"funders\":[],\"hasAdminPriorityOnWorkflow\":false,\"hasManuscriptDocX\":false,\"hasOptedInToPreprint\":true,\"hasPassedJournalQc\":\"\",\"hasAnyPriority\":true,\"hideJournal\":false,\"highlight\":\"\",\"institution\":\"\",\"isAcceptedByJournal\":false,\"isAuthorSuppliedPdf\":true,\"isDeskRejected\":\"\",\"isHiddenFromSearch\":false,\"isInQc\":false,\"isInWorkflow\":false,\"isPdf\":true,\"isPdfUpToDate\":true,\"isWithdrawnOrRetracted\":false,\"journal\":{\"display\":true,\"email\":\"info@researchsquare.com\",\"identity\":\"nature-portfolio\",\"isNatureJournal\":true,\"hasQc\":false,\"allowDirectSubmit\":false,\"externalIdentity\":\"\",\"sideBox\":\"\",\"snPcode\":\"\",\"submissionUrl\":\"\",\"title\":\"Nature Portfolio\",\"twitterHandle\":\"\",\"acdcEnabled\":false,\"dfaEnabled\":false,\"editorialSystem\":\"ejp\",\"reportingPortfolio\":\"\",\"inReviewEnabled\":true,\"inReviewRevisionsEnabled\":false},\"keywords\":\"\",\"lastPublishedDoi\":\"10.21203/rs.3.rs-7142999/v1\",\"lastPublishedDoiUrl\":\"https://doi.org/10.21203/rs.3.rs-7142999/v1\",\"license\":{\"name\":\"CC BY 4.0\",\"url\":\"https://creativecommons.org/licenses/by/4.0/\"},\"manuscriptAbstract\":\"Inflammatory brain damage is an important factor contributing to mortality or lasting neurological sequelae in CNS infections, such as cryptococcal meningoencephalitis (CM), but little is known about natural immunoregulatory mechanisms in the infected brain. Here we report that regulatory T cells (Tregs) are a central immunoregulatory component in CM. Tregs are present within the CNS in both human CM patients and in the experimental murine CM. Treg-depletion exacerbates Th1-driven brain inflammation and neurological symptoms, accelerating mortality, despite enhanced fungal clearance in mouse CM. Aligned brain NanoString, scRNA-seq, and flow cytometry analyses revealed that Tregs reduce brain inflammation, especially T-cell recruitment activation and differentiation, shielding the brain from neurological damage. The major CNS-Treg recruitment appears to be chemokine receptor CCR8-mediated, supporting the importance of the CCR8/CCL1 axis in Treg recruitment into the brain. Tregs in CM are major producers of anti-inflammatory IL-10 and the growth factor Amphiregulin (Areg), which is implicated in neuronal repair. IL-10 deletion in murine CM phenocopies Treg depletion. Areg deletion showed no survival effect; however, IFN-γ production by effector T cells in the brain was reduced, supporting Aregs as a potential internal regulator of Treg immunosuppressive function. Finally, a Treg-enhancing immunotherapy using low dose IL-2-immune complex treatment substantially improves mouse survival and neurological outcomes. Together, we identified that Tregs are crucial for neuronal protection in CM, predominantly via IL-10 production, the CCR8-CCL1 axis is an important CNS-Treg recruitment mechanism and Treg enhancement is a potential therapeutic strategy to mitigate immunopathology during CM, and possibly other forms of meningitis.\",\"manuscriptTitle\":\"Foxp3+ Regulatory T Cells Restrain Th1 Response Shielding the Brain from Lethal Inflammatory Damage during Cryptococcal Meningoencephalitis\",\"msid\":\"\",\"msnumber\":\"\",\"nonDraftVersions\":[{\"code\":1,\"date\":\"2025-07-30 10:40:45\",\"doi\":\"10.21203/rs.3.rs-7142999/v1\",\"editorialEvents\":[],\"status\":\"published\",\"journal\":{\"display\":true,\"email\":\"info@researchsquare.com\",\"identity\":\"nature-microbiology\",\"isNatureJournal\":true,\"hasQc\":false,\"allowDirectSubmit\":false,\"externalIdentity\":\"nmicrobiol\",\"sideBox\":\"Learn more about [Nature Microbiology](http://www.nature.com/nmicrobiol/)\",\"snPcode\":\"\",\"submissionUrl\":\"\",\"title\":\"Nature Microbiology\",\"twitterHandle\":\"\",\"acdcEnabled\":true,\"dfaEnabled\":true,\"editorialSystem\":\"ejp\",\"reportingPortfolio\":\"Nature Research\",\"inReviewEnabled\":true,\"inReviewRevisionsEnabled\":false}}],\"origin\":\"\",\"ownerIdentity\":\"4921fc62-5cb9-453f-98e2-3712ee60abb4\",\"owner\":[],\"postedDate\":\"July 30th, 2025\",\"published\":true,\"recentEditorialEvents\":[],\"rejectedJournal\":[],\"revision\":\"\",\"amendment\":\"\",\"status\":\"under-review\",\"subjectAreas\":[{\"id\":52353437,\"name\":\"Biological sciences/Microbiology/Fungi/Fungal host response\"},{\"id\":52353438,\"name\":\"Health sciences/Pathogenesis/Infection\"},{\"id\":52353439,\"name\":\"Health sciences/Diseases/Infectious diseases/Fungal infection\"}],\"tags\":[],\"updatedAt\":\"2025-09-09T10:56:35+00:00\",\"versionOfRecord\":[],\"versionCreatedAt\":\"2025-07-30 10:40:45\",\"video\":\"\",\"vorDoi\":\"\",\"vorDoiUrl\":\"\",\"workflowStages\":[]},\"version\":\"v1\",\"identity\":\"rs-7142999\",\"journalConfig\":\"researchsquare\"},\"__N_SSP\":true},\"page\":\"/article/[identity]/[[...version]]\",\"query\":{\"redirect\":\"/article/rs-7142999\",\"identity\":\"rs-7142999\",\"version\":[\"v1\"]},\"buildId\":\"XKTyCvWXoU3ODBz1xrDgd\",\"isFallback\":false,\"isExperimentalCompile\":false,\"dynamicIds\":[84888],\"gssp\":true,\"scriptLoader\":[]}","source_license":"CC-BY-4.0","license_restricted":false}