TSU-MAN CHIU2026-10-162026-10-162023-10-01Pure ID: 15245014Pure UUID: 3a782ef2-2113-44f7-9b0c-dbf0ad0f2d7610.1016/j.clim.2023.109737https://www.scopus.com/pages/publications/85168478380https://scholars.csmu.edu.tw/handle/123456789/23746Background: The clinical characteristics and pathomechanism for immune-mediated alopecia following COVID-19 vaccinations are not clearly characterized. Objective: We investigated the causality and immune mechanism of COVID-19 vaccines-related alopecia areata (AA). Study design: 27 new-onset of AA patients after COVID-19 vaccinations and 106 vaccines-tolerant individuals were enrolled from multiple medical centers for analysis. Results: The antinuclear antibody, total IgE, granulysin, and PARC/CCL18 as well as peripheral eosinophil count were significantly elevated in the patients with COVID-19 vaccines-related AA compared with those in the tolerant individuals (P = 2.03 × 10−5-0.039). In vitro lymphocyte activation test revealed that granulysin, granzyme B, and IFN-γ released from the T cells of COVID-19 vaccines-related AA patients could be significantly increased by COVID-19 vaccine excipients (polyethylene glycol 2000 and polysorbate 80) or spike protein (P = 0.002–0.04). Conclusions: Spike protein and excipients of COVID-19 vaccines could trigger T cell-mediated cytotoxicity, which contributes to the pathogenesis of immune-mediated alopecia associated with COVID-19 vaccines.enjournal article