{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,17]],"date-time":"2026-09-17T12:00:29Z","timestamp":1789646429298,"version":"4.0.0"},"update-to":[{"DOI":"10.1371\/journal.ppat.1011509","type":"new_version","label":"New version","source":"publisher","updated":{"date-parts":[[2023,8,16]],"date-time":"2023-08-16T00:00:00Z","timestamp":1692144000000}}],"reference-count":43,"publisher":"Public Library of Science (PLoS)","issue":"8","license":[{"start":{"date-parts":[[2023,8,4]],"date-time":"2023-08-04T00:00:00Z","timestamp":1691107200000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100006492","name":"Division of Intramural Research, National Institute of Allergy and Infectious Diseases","doi-asserted-by":"publisher","award":["R01 AI50893"],"award-info":[{"award-number":["R01 AI50893"]}],"id":[{"id":"10.13039\/100006492","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100006492","name":"Division of Intramural Research, National Institute of Allergy and Infectious Diseases","doi-asserted-by":"publisher","award":["R37 AI38446"],"award-info":[{"award-number":["R37 AI38446"]}],"id":[{"id":"10.13039\/100006492","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100006492","name":"Division of Intramural Research, National Institute of Allergy and Infectious Diseases","doi-asserted-by":"publisher","award":["R21 AI50867"],"award-info":[{"award-number":["R21 AI50867"]}],"id":[{"id":"10.13039\/100006492","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["www.plospathogens.org"],"crossmark-restriction":false},"short-container-title":["PLoS Pathog"],"abstract":"<jats:p>\n                    Among the many oral streptococci,\n                    <jats:italic>Streptococcus pneumoniae<\/jats:italic>\n                    (\n                    <jats:italic>Spn<\/jats:italic>\n                    ) stands out for the capacity of encapsulated strains to cause invasive infection. Spread beyond upper airways, however, is a biological dead end for the organism, raising the question of the benefits of expending energy to coat its surface in a thick layer of capsular polysaccharide (CPS). In this study, we compare mutants of two serotypes expressing different amounts of CPS and test these in murine models of colonization, invasion infection and transmission. Our analysis of the effect of CPS amount shows that\n                    <jats:italic>Spn<\/jats:italic>\n                    expresses a capsule of sufficient thickness to shield its surface from the deposition of complement and binding of antibody to underlying epitopes. While effective shielding is permissive for invasive infection, its primary contribution to the organism appears to be in the dynamics of colonization. A thicker capsule increases bacterial retention in the nasopharynx, the first event in colonization, and also impedes IL-17-dependent clearance during late colonization. Enhanced colonization is associated with increased opportunity for host-to-host transmission. Additionally, we document substantial differences in CPS amount among clinical isolates of three common serotypes. Together, our findings show that CPS amount is highly variable among\n                    <jats:italic>Spn<\/jats:italic>\n                    and could be an independent determinant affecting host interactions.\n                  <\/jats:p>","DOI":"10.1371\/journal.ppat.1011509","type":"journal-article","created":{"date-parts":[[2023,8,4]],"date-time":"2023-08-04T13:36:10Z","timestamp":1691156170000},"page":"e1011509","update-policy":"https:\/\/doi.org\/10.1371\/journal.ppat.corrections_policy","source":"Crossref","is-referenced-by-count":24,"title":["Effects of Capsular Polysaccharide amount on Pneumococcal-Host interactions"],"prefix":"10.1371","volume":"19","author":[{"given":"Jiaqi","family":"Zhu","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Annie 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