{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,27]],"date-time":"2026-08-27T13:22:33Z","timestamp":1787836953432,"version":"build-2784847793"},"reference-count":53,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,8,27]],"date-time":"2026-08-27T00:00:00Z","timestamp":1787788800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Immunol."],"abstract":"<jats:p>Persistent inflammation and tissue injury may contribute to post-acute COVID-19 syndrome (PACS). However, direct tissue evidence from mildly-infected individuals sampled long after recovery remains exceptionally limited. Here, we performed post-mortem bulk RNA-seq and GeoMx digital spatial profiling of lung, heart, and brain tissues from four individuals who recovered from mild COVID-19 more than 250 days before death from unrelated causes. Samples were collected during the early phase of the national vaccination program, before widespread vaccine uptake and recurrent infection, providing a rare reference cohort for defining tissue responses to SARS-CoV-2 in the absence of major confounding from vaccination and\/or reinfection; such a cohort can no longer be prospectively assembled. We observed residual SARS-CoV-2 nucleocapsid antigen within tissues and revealed organ-specific immune alterations. Lung and heart tissues exhibited a coordinated, self-sustaining inflammatory response, whereas brain tissue showed vascular dysfunction and altered neuroimmune homeostasis. These findings showcase the distinct tissue responses following mild infection and provide a spatially resolved view of sub-clinical long-term tissue sequelae. Collectively, our data establish a unique baseline for persistent viral antigen and tissue-specific immune dysregulation underlying PACS.<\/jats:p>","DOI":"10.3389\/fimmu.2026.1913045","type":"journal-article","created":{"date-parts":[[2026,8,27]],"date-time":"2026-08-27T13:02:26Z","timestamp":1787835746000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Case Report: Post-mortem analysis of long-term inflammation after mild COVID-19"],"prefix":"10.3389","volume":"17","author":[{"given":"Yang","family":"Wu","sequence":"first","affiliation":[{"name":"Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology and Research (A*STAR)","place":["Singapore, Singapore"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yu Kit","family":"Chan","sequence":"additional","affiliation":[{"name":"National Centre for Infectious Diseases","place":["Singapore, Singapore"]},{"name":"Department of 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