{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T18:52:47Z","timestamp":1790189567649,"version":"4.1.0"},"reference-count":34,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2026,6,9]],"date-time":"2026-06-09T00:00:00Z","timestamp":1780963200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Life"],"abstract":"<jats:p>Mechanisms of arboviral neuroinvasion are still incompletely resolved, despite longstanding emphasis on the blood-brain barrier (BBB) as the principal interface for central nervous system (CNS) entry. While BBB-centered models have been highly informative, they may underrepresent the contribution of other CNS border structures, particularly the choroid plexus and the blood-cerebrospinal fluid barrier (BCSFB). Here, we re-examine the BCSFB as a relevant but unevenly supported neuroinvasion interface in arboviral encephalitis. The strongest direct evidence is currently available for Zika virus (ZIKV), for which experimental studies support infection of choroid plexus-associated cells and CNS access through the blood-CSF axis. Semliki Forest virus (SFV) provides additional direct, although still limited, support for this concept. In contrast, for West Nile virus (WNV), Japanese encephalitis virus (JEV), and tick-borne encephalitis virus (TBEV), evidence for choroid plexus involvement remains indirect or insufficiently resolved, even though neuroinvasion itself is well established. We therefore argue not for replacement of BBB-centered models, but for broader integration of the BCSFB into current frameworks of arboviral CNS invasion. This evidence-based perspective supports a hierarchical, virus-dependent view of choroid plexus involvement and highlights the need for mechanistic studies that directly test when and how this interface contributes to encephalitic disease.<\/jats:p>","DOI":"10.3390\/life16060975","type":"journal-article","created":{"date-parts":[[2026,6,11]],"date-time":"2026-06-11T06:57:17Z","timestamp":1781161037000},"page":"975","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["The Forgotten Gate: Choroid Plexus and Blood-CSF Barrier in Arboviral Encephalitis"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0009-0003-9328-1736","authenticated-orcid":false,"given":"Cec\u00edlia M.","family":"Wodzik","sequence":"first","affiliation":[{"name":"Laboratory of Fish Physiology and Biotechnology (LabFISH), Department of Biosciences, Federal University of Jata\u00ed (UFJ), Jata\u00ed 75801-615, GO, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0249-3211","authenticated-orcid":false,"given":"Matheus Henrique B.","family":"Figueiredo","sequence":"additional","affiliation":[{"name":"Laboratory of Fish Physiology and Biotechnology (LabFISH), Department of Biosciences, Federal University of Jata\u00ed (UFJ), Jata\u00ed 75801-615, GO, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0006-3888-5758","authenticated-orcid":false,"given":"Paula S.","family":"Nakamura","sequence":"additional","affiliation":[{"name":"Laboratory of Fish Physiology and Biotechnology (LabFISH), Department of Biosciences, Federal University of Jata\u00ed (UFJ), Jata\u00ed 75801-615, GO, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"M\u00f4nica Rodrigues F.","family":"Machado","sequence":"additional","affiliation":[{"name":"Laboratory of Fish Physiology and Biotechnology (LabFISH), Department of Biosciences, Federal University of Jata\u00ed (UFJ), Jata\u00ed 75801-615, GO, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9359-0198","authenticated-orcid":false,"given":"Vivaldo G. da","family":"Costa","sequence":"additional","affiliation":[{"name":"Genomics Laboratory, Department of Biology, S\u00e3o Paulo State University (UNESP), S\u00e3o Jos\u00e9 do Rio Preto 15054-000, SP, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rafael M. da","family":"Costa","sequence":"additional","affiliation":[{"name":"Laboratory of Cardiovascular Pharmacology and Toxicology (LAFTOCAR), Department of Health Sciences, Federal University of Jata\u00ed (UFJ), Jata\u00ed 75801-615, GO, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7627-621X","authenticated-orcid":false,"given":"Marielena V.","family":"Saivish","sequence":"additional","affiliation":[{"name":"Laboratory of Virology Research, Department of Dermatological, Infectious and Parasitic Diseases, School of Medicine of S\u00e3o Jos\u00e9 do Rio Preto (FAMERP), S\u00e3o Jos\u00e9 do Rio Preto 15090-000, SP, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,6,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Marshall, E.M., Koopmans, M.P.G., and Rockx, B. 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