{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,8]],"date-time":"2026-09-08T11:06:48Z","timestamp":1788865608801,"version":"build-2803163510"},"reference-count":46,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2026,9,8]],"date-time":"2026-09-08T00:00:00Z","timestamp":1788825600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001631","name":"UCD Seed Funding Grant","doi-asserted-by":"publisher","award":["SF1592"],"award-info":[{"award-number":["SF1592"]}],"id":[{"id":"10.13039\/501100001631","id-type":"DOI","asserted-by":"publisher"}]},{"name":"UCD School of Veterinary Medicine OIP Grant","award":["R21299"],"award-info":[{"award-number":["R21299"]}]},{"name":"UCD Lyons Translational Research Unit"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>This prospective, randomised, ex vivo study investigated the effects of manual double-spin centrifugation protocols on the cellular and growth factor composition of equine platelet-rich plasma (PRP). Blood from 20 healthy horses was evaluated in two phases. In Phase A (n = 10), nine first-spin protocols were compared, and two were selected based on platelet enrichment and leukocyte reduction. In Phase B (n = 10), these were combined with nine second-spin conditions, generating 18 PRP preparations. Platelet (PLT), leukocyte (WBC) and erythrocyte (RBC) concentrations and PDGF-BB and TGF-\u03b21 concentrations were measured. No significant differences in cellular composition were identified among first-spin protocols (p &gt; 0.05). From Phase B, all final preparations achieved platelet enrichment and leukocyte depletion, with negligible RBC contamination. Second-spin force significantly affected PDGF-BB and TGF-\u03b21 concentrations (p &lt; 0.001). PDGF-BB increased from 2629 pg\/mL (95% CI: 2111\u20133274) at 200\u00d7 g to 3467 pg\/mL (95% CI: 2784\u20134317) at 1000\u00d7 g, while TGF-\u03b21 increased from 13,364 pg\/mL (95% CI: 11,286\u201315,824) to 16,998 pg\/mL (95% CI: 14,355\u201320,127). TGF-\u03b21 also increased with second-spin duration (p = 0.01). Platelet concentration was positively correlated with PDGF-BB (\u03c1 = 0.604) and TGF-\u03b21 (\u03c1 = 0.691; both p &lt; 0.001), whereas WBC concentration showed no significant association with either growth factor. Thus, both preparation methodology and donor-related variability influence equine PRP composition, indicating that protocol standardisation alone is unlikely to ensure biologically consistent PRP products.<\/jats:p>","DOI":"10.3390\/ani16182824","type":"journal-article","created":{"date-parts":[[2026,9,8]],"date-time":"2026-09-08T10:00:04Z","timestamp":1788861604000},"page":"2824","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Influence of Manual Double-Spin Preparation Protocols on the Cellular and Growth Factor Composition of Equine Platelet-Rich Plasma"],"prefix":"10.3390","volume":"16","author":[{"given":"Andrea","family":"del Rincon","sequence":"first","affiliation":[{"name":"School of Veterinary Medicine, University College Dublin, Belfield, D04 W6F6 Dublin, Ireland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3893-2041","authenticated-orcid":false,"given":"Michael J. S.","family":"Duggan","sequence":"additional","affiliation":[{"name":"School of Veterinary Medicine, University College Dublin, Belfield, D04 W6F6 Dublin, Ireland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Milda","family":"Baltrimaite","sequence":"additional","affiliation":[{"name":"School of Veterinary Medicine, University College Dublin, Belfield, D04 W6F6 Dublin, Ireland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aoife","family":"O\u2019Kane","sequence":"additional","affiliation":[{"name":"School of Veterinary Medicine, University College Dublin, Belfield, D04 W6F6 Dublin, Ireland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8665-1266","authenticated-orcid":false,"given":"John Mark","family":"O\u2019Leary","sequence":"additional","affiliation":[{"name":"School of Veterinary Medicine, University College Dublin, Belfield, D04 W6F6 Dublin, Ireland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3405-0551","authenticated-orcid":false,"given":"Pieter A. J.","family":"Brama","sequence":"additional","affiliation":[{"name":"School of Veterinary Medicine, University College Dublin, Belfield, D04 W6F6 Dublin, Ireland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Clodagh","family":"Kearney","sequence":"additional","affiliation":[{"name":"School of Veterinary Medicine, University College Dublin, Belfield, D04 W6F6 Dublin, Ireland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"225","DOI":"10.1016\/j.tibtech.2020.07.011","article-title":"Platelet-Derived Products in Veterinary Medicine: A New Trend or an Effective Therapy?","volume":"39","author":"Soares","year":"2021","journal-title":"Trends Biotechnol."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Camargo Garbin, L., Lopez, C., and Carmona, J.U. (2021). 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