TY - JOUR AB - elets function as immune cells in conjunction with white blood cells, targeting invading pathogens and inducing immune reactions. Intercellular communications among these immune cells are partly mediated by platelet polyphosphate (polyP), which was originally recognized as a thrombotic and hemostatic biomolecule. To determine the involvement of polyP in SARS‑CoV‑2‑mRNA vaccine‑induced immune responses, specifically in inflammatory responses, the effects of mRNA vaccines on platelet polyP levels were examined. Before and after vaccination with the COVID‑19 vaccine (BNT162b2), blood samples were obtained from healthy, non‑smoking individuals who did not have any systemic diseases. Test group demographics skewed somewhat towards either older males (first vaccination, n=6; second vaccination, n=8) or younger females (first vaccination, n=14; second vaccination, n=23). polyP levels in washed platelets from the blood samples were determined using the fluorometric method with DAPI. The side-effects of vaccination were recorded as scores. In the female group, platelet polyP levels decreased after the first vaccination, and the side-effect score increased after the second vaccination. Moderate correlation coefficients were observed between the reduction in polyP levels and the side-effect scores and pre‑vaccination polyP levels. Despite the small sample size, this pilot study suggests that platelet polyP may suppress the side effects induced by the mRNA vaccines after the first vaccination, but not the second vaccination in younger female subjects, who generally have higher immune responsiveness than their male counterparts. AD - Tokyo Plastic Dental Society, Tokyo 114‑0002, Japan Department of Materials, Science and Technology, Niigata University, Niigata 950‑2181, Japan Division of Oral Bioengineering, Niigata University Graduate School of Medical and Dental Sciences, Niigata 951‑8514, Japan AU - Uematsu,Takashi AU - Sato,Atsushi AU - Aizawa,Hachidai AU - Tsujino,Tetsuhiro AU - Watanabe,Taisuke AU - Isobe,Kazushige AU - Kawabata,Hideo AU - Kitamura,Yutaka AU - Tanaka,Takaaki AU - Kawase,Tomoyuki DA - 2022/03/01 DO - 10.3892/br.2022.1504 IS - 3 JO - Biomed Rep KW - COVID‑19 mRNA vaccine blood platelet polyphosphates sex side effects PY - 2022 SN - 2049-9434 2049-9442 SP - 21 ST - Effects of SARS‑CoV‑2 mRNA vaccines on platelet polyphosphate levels and inflammation: A pilot study T2 - Biomedical Reports TI - Effects of SARS‑CoV‑2 mRNA vaccines on platelet polyphosphate levels and inflammation: A pilot study UR - https://doi.org/10.3892/br.2022.1504 VL - 16 ER -