{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,5]],"date-time":"2026-06-05T05:06:44Z","timestamp":1780636004249,"version":"3.54.1"},"reference-count":51,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,6,5]],"date-time":"2026-06-05T00:00:00Z","timestamp":1780617600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100009846","name":"Nova Southeastern University","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100009846","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Immunol."],"abstract":"<jats:p>\n                    Myalgic encephalomyelitis\/chronic fatigue syndrome (ME\/CFS) is a disease of unknown etiology associated with chronic severe fatigue and neurological symptoms, including dizziness, sleep disturbances, cognitive impairment and pain. There are no reliable blood biomarkers available for ME\/CFS, possibly due to the lack of specific pathogenesis, even though Epstein-Barr Virus (EBV) has been suspected. We quantified the levels of interleukin-11 (IL-11) in the serum of female ME\/CFS patients (n = 40; mean age 51 years) and age- and gender-matched healthy control subjects (n = 38; mean age 43), as well as matrix metalloproteinase-9 (MMP-9) in ME\/CFS patients (n = 18; mean age 57 years old) and healthy control subjects (n = 18; mean age 53 years old), using an enzyme-linked immunosorbent assay (ELISA). We hypothesized that mast cells (MC) stimulated by EBV may be involved. MC are unique tissue immune cells that have been implicated in ME\/CFS. MC were grown from human umbilical cord blood CD34\n                    <jats:sup>+<\/jats:sup>\n                    stem cells\n                    <jats:italic>in vitro<\/jats:italic>\n                    and incubated with recombinant (rEBV) protein, following which the release of MMP-9 was assayed in the cell culture supernatant media by ELISA. There was a significant increase in serum levels of IL-11 and MMP-9 in ME\/CFS patients compared to control subjects. MCs stimulated by rEBV protein released a high amount of MMP-9 compared to control cells. In conclusion, IL-11, MMP-9 and MCs may be involved in ME\/CFS individuals.\n                  <\/jats:p>","DOI":"10.3389\/fimmu.2026.1827700","type":"journal-article","created":{"date-parts":[[2026,6,5]],"date-time":"2026-06-05T04:48:31Z","timestamp":1780634911000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Elevated serum levels of interleukin-11 and matrix metalloproteinase-9 in myalgic encephalomyelitis\/chronic fatigue syndrome"],"prefix":"10.3389","volume":"17","author":[{"given":"Baskaran","family":"Chinnappan","sequence":"first","affiliation":[{"name":"Institute for Neuro-Immune Medicine, Dr. Kiran C. Patel College of Osteopathic Medicine, Nova Southeastern University","place":["Ft. 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Lauderdale, FL, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sai Puneeth","family":"Kothuru","sequence":"additional","affiliation":[{"name":"Institute for Neuro-Immune Medicine, Dr. Kiran C. Patel College of Osteopathic Medicine, Nova Southeastern University","place":["Ft. Lauderdale, FL, United States"]},{"name":"College of Psychology, Nova Southeastern University","place":["Ft. Lauderdale, FL, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rhitik Samir","family":"Joshi","sequence":"additional","affiliation":[{"name":"Institute for Neuro-Immune Medicine, Dr. Kiran C. Patel College of Osteopathic Medicine, Nova Southeastern University","place":["Ft. Lauderdale, FL, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nancy G.","family":"Klimas","sequence":"additional","affiliation":[{"name":"Institute for Neuro-Immune Medicine, Dr. Kiran C. Patel College of Osteopathic Medicine, Nova Southeastern University","place":["Ft. Lauderdale, FL, United States"]},{"name":"Miami Veterans Affairs (VA) Geriatric Research Education and Clinical Center (GRECC), Miami Veterans Affairs Healthcare System","place":["Miami, FL, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Theoharis C.","family":"Theoharides","sequence":"additional","affiliation":[{"name":"Institute for Neuro-Immune Medicine, Dr. Kiran C. Patel College of Osteopathic Medicine, Nova Southeastern University","place":["Ft. 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