{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,16]],"date-time":"2026-08-16T13:41:28Z","timestamp":1786887688580,"version":"build-2736575974"},"reference-count":22,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2026,5,13]],"date-time":"2026-05-13T00:00:00Z","timestamp":1778630400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Cells"],"abstract":"<jats:p>Introduction: Orthobiologics such as Platelet-Rich Plasma (PRP) and Injectable Platelet-Rich Fibrin (i-PRF) have emerged as promising tools in regenerative medicine. However, the lack of methodological standardization and the still limited comparative characterization between these products represent significant barriers to their optimized clinical application. This comparative laboratory study aimed to characterize and differentiate PRP and i-PRF, focusing on their cellular composition, obtained volume, and total Platelet-Derived Growth Factor (PDGF-BB) content. Materials and Methods: This study was conducted with 34 individuals meeting standard blood donation criteria. Peripheral blood samples were collected from all participants. PRP was obtained using a modified double-spin centrifugation protocol, whereas i-PRF was prepared using a modified low-speed centrifugation technique. Cellularity (platelet and leukocyte counts), final produced volume, and total PDGF-BB content were assessed using complete blood count analysis and an enzyme-linked immunosorbent assay (ELISA), respectively. Statistical analysis was performed using Linear Mixed Models (LMMs). Results: Both protocols resulted in significant increases in platelet and leukocyte concentrations compared to baseline values. PRP showed significantly higher platelet and leukocyte concentrations compared with i-PRF, as well as markedly higher PDGF-BB levels. In contrast, i-PRF yielded a substantially greater final volume and enabled a higher absolute delivery of total leukocytes, whereas PRP delivered a greater absolute number of platelets. In exploratory analyses, female sex, the presence of comorbidities, and increased abdominal circumference were associated with variations in product volume and cellular composition. Discussion: These findings indicate that PRP and i-PRF exhibit distinct biological profiles in terms of cellularity, volume, and total PDGF-BB content. Whether these laboratory differences translate into distinct clinical outcomes remains unknown. The results should therefore be viewed as hypothesis-generating: they suggest that PRP and i-PRF may not be interchangeable, and that future randomized clinical trials are needed to define product-specific indications based on the target tissue and desired biological mechanism.<\/jats:p>","DOI":"10.3390\/cells15100886","type":"journal-article","created":{"date-parts":[[2026,5,25]],"date-time":"2026-05-25T06:42:18Z","timestamp":1779691338000},"page":"886","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Comparative Characterization of Leukocyte-Rich Platelet-Rich Plasma (L-PRP) and Injectable Platelet-Rich Fibrin (i-PRF): A Laboratory Study"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7415-3953","authenticated-orcid":false,"given":"Andr\u00e9 Vinicius Saueressig","family":"Kruel","sequence":"first","affiliation":[{"name":"Cl\u00ednica PROREGEN, Bento Gon\u00e7alves 95700-066, RS, Brazil"},{"name":"Programa de P\u00f3s-Gradua\u00e7\u00e3o em Biotecnologia (PPGBiotec), Universidade do Vale do Taquari (Univates), Lajeado 95914-014, RS, Brazil"},{"name":"Programa de P\u00f3s-Gradua\u00e7\u00e3o em Ci\u00eancias M\u00e9dicas (PPGCM), Universidade do Vale do Taquari (Univates), Lajeado 95914-014, RS, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mari\u00e2ngela","family":"Ferreira","sequence":"additional","affiliation":[{"name":"Cl\u00ednica PROREGEN, Bento Gon\u00e7alves 95700-066, RS, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0003-8810-5383","authenticated-orcid":false,"given":"Daiane","family":"Agostini","sequence":"additional","affiliation":[{"name":"Cl\u00ednica PROREGEN, Bento Gon\u00e7alves 95700-066, RS, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cristiano Valter","family":"Diesel","sequence":"additional","affiliation":[{"name":"Hospital Moinhos de Vento, Porto Alegre 90560-032, RS, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marcelo","family":"Queiroz","sequence":"additional","affiliation":[{"name":"Hospital Israelita Albert Einstein, S\u00e3o Paulo 05651-901, SP, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Carlos Roberto","family":"Galia","sequence":"additional","affiliation":[{"name":"Hospital de Cl\u00ednicas de Porto Alegre, Porto Alegre 90410-000, RS, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6619-6622","authenticated-orcid":false,"given":"Guilherme Liberato","family":"da Silva","sequence":"additional","affiliation":[{"name":"Programa de P\u00f3s-Gradua\u00e7\u00e3o em Ci\u00eancias M\u00e9dicas (PPGCM), Universidade do Vale do Taquari (Univates), Lajeado 95914-014, RS, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3322-0598","authenticated-orcid":false,"given":"Stephany","family":"Huber","sequence":"additional","affiliation":[{"name":"Orthoregen Medicina, Ensino e Pesquisa, Indaiatuba 13334-170, SP, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fernanda","family":"Majolo","sequence":"additional","affiliation":[{"name":"Programa de P\u00f3s-Gradua\u00e7\u00e3o em Biotecnologia (PPGBiotec), Universidade do Vale do Taquari (Univates), Lajeado 95914-014, RS, Brazil"},{"name":"Programa de P\u00f3s-Gradua\u00e7\u00e3o em Ci\u00eancias M\u00e9dicas (PPGCM), Universidade do Vale do Taquari (Univates), Lajeado 95914-014, RS, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,5,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Lana, J.F.S., Santana, M.H.A., Belangero, W.D., and Luzo, A.C.M. (2013). Platelet-Rich Plasma: Regenerative Medicine, Sports Medicine, Orthopedic, and Recovery of Musculoskeletal Injuries, Springer.","DOI":"10.1007\/978-3-642-40117-6"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"3971","DOI":"10.1038\/s41598-021-83025-2","article-title":"Platelet-rich plasma (PRP) in osteoarthritis (OA) knee: Correct dose critical for long-term clinical efficacy","volume":"11","author":"Bansal","year":"2021","journal-title":"Sci. Rep."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"304","DOI":"10.4252\/wjsc.v13.i4.304","article-title":"Orthobiologics in the treatment of hip disorders","volume":"13","author":"Kruel","year":"2021","journal-title":"World J. Stem Cells"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"225","DOI":"10.1097\/00008505-200110000-00002","article-title":"Platelet-rich plasma (PRP): What is PRP and what is not PRP?","volume":"10","author":"Marx","year":"2001","journal-title":"Implant Dent."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"638","DOI":"10.1016\/S1079-2104(98)90029-4","article-title":"Platelet-rich plasma: Growth factor enhancement for bone grafts","volume":"85","author":"Marx","year":"1998","journal-title":"Oral Surg. Oral Med. Oral Pathol. Oral Radiol. Endod."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"900","DOI":"10.1055\/s-0042-1744223","article-title":"Influential studies in orthopaedic platelet-rich plasma research are recent and consist of high levels of evidence: A review of the top 50 most cited publications","volume":"36","author":"Oeding","year":"2023","journal-title":"J. Knee Surg."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"3147","DOI":"10.1177\/03635465231224463","article-title":"Platelet-rich plasma versus alternative injections for osteoarthritis of the knee: A systematic review and statistical fragility index-based meta-analysis of randomized controlled trials","volume":"52","author":"Oeding","year":"2024","journal-title":"Am. J. Sports Med."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"463","DOI":"10.1177\/0363546513494359","article-title":"Efficacy of platelet-rich plasma for chronic tennis elbow: A double-blind, prospective, multicenter, randomized controlled trial of 230 patients","volume":"42","author":"Mishra","year":"2014","journal-title":"Am. J. Sports Med."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"1130","DOI":"10.1177\/0363546519826969","article-title":"Leucocyte-rich platelet-rich plasma treatment of gluteus medius and minimus tendinopathy: A double-blind randomized controlled trial with 2-year follow-up","volume":"47","author":"Fitzpatrick","year":"2019","journal-title":"Am. J. Sports Med."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"1769","DOI":"10.2106\/JBJS.16.01374","article-title":"A call for standardization in platelet-rich plasma preparation protocols and composition reporting: A systematic review of the clinical orthopaedic literature","volume":"99","author":"Chahla","year":"2017","journal-title":"J. Bone Jt. Surg. Am."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"565","DOI":"10.2217\/rme-2017-0042","article-title":"Contributions for classification of platelet-rich plasma: Proposal of a new classification\u2014MARSPILL","volume":"12","author":"Lana","year":"2017","journal-title":"Regen. Med."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"e37","DOI":"10.1016\/j.tripleo.2005.07.008","article-title":"Platelet-rich fibrin (PRF): A second-generation platelet concentrate. Part I: Technological concepts and evolution","volume":"101","author":"Dohan","year":"2006","journal-title":"Oral Surg. Oral Med. Oral Pathol. Oral Radiol. Endod."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"e56","DOI":"10.1016\/j.tripleo.2005.07.011","article-title":"Platelet-rich fibrin (PRF): A second-generation platelet concentrate. Part IV: Clinical effects on tissue healing","volume":"101","author":"Choukroun","year":"2006","journal-title":"Oral Surg. Oral Med. Oral Pathol. Oral Radiol. Endod."},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Narayanaswamy, R., Patro, B.P., Jeyaraman, N., Gangadaran, P., Rajendran, R.L., Nallakumarasamy, A., Jeyaraman, M., Ramani, P., and Ahn, B.-C. (2023). Evolution and clinical advances of platelet-rich fibrin in musculoskeletal regeneration. Bioengineering, 10.","DOI":"10.3390\/bioengineering10010058"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"3625","DOI":"10.1016\/S0021-9258(18)53739-X","article-title":"Mechanism of platelet-derived growth factor (PDGF) AA, AB, and BB binding to alpha and beta PDGF receptor","volume":"268","author":"Fretto","year":"1993","journal-title":"J. Biol. Chem."},{"key":"ref_16","unstructured":"World Health Organization (WHO) (2012). Blood Donor Selection: Guidelines on Assessing Donor Suitability for Blood Donation, WHO Press. Available online: https:\/\/apps.who.int\/iris\/handle\/10665\/76724."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"67","DOI":"10.1186\/scrt218","article-title":"Platelet-rich plasma preparation for regenerative medicine: Optimization and quantification of cytokines and growth factors","volume":"4","author":"Amable","year":"2013","journal-title":"Stem Cell Res. Ther."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"2","DOI":"10.46582\/jsrm.1201002","article-title":"In vitro study of the role of thrombin in platelet-rich plasma (PRP) preparation: Utility for gel formation and impact on growth factor release","volume":"12","author":"Huber","year":"2016","journal-title":"J. Stem Cells Regen. Med."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"87","DOI":"10.1007\/s00068-017-0767-9","article-title":"Reduction of relative centrifugation force within injectable platelet-rich fibrin (PRF) concentrates advances patients\u2019 own inflammatory cells, platelets and growth factors: The first introduction to the low-speed centrifugation concept","volume":"44","author":"Choukroun","year":"2018","journal-title":"Eur. J. Trauma Emerg. Surg."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"2353","DOI":"10.1007\/s00784-016-1719-1","article-title":"Comparative release of growth factors from PRP, PRF, and advanced-PRF","volume":"20","author":"Kobayashi","year":"2016","journal-title":"Clin. Oral Investig."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"199","DOI":"10.1016\/j.thromres.2005.06.021","article-title":"Platelet count, mean platelet volume and thrombocytopoietic indices in healthy women and men","volume":"118","author":"Butkiewicz","year":"2006","journal-title":"Thromb. Res."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"41","DOI":"10.1016\/j.blre.2013.12.003","article-title":"The sex difference in haemoglobin levels in adults\u2014Mechanisms, causes, and consequences","volume":"28","author":"Murphy","year":"2014","journal-title":"Blood Rev."}],"container-title":["Cells"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2073-4409\/15\/10\/886\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,5,25]],"date-time":"2026-05-25T06:51:52Z","timestamp":1779691912000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2073-4409\/15\/10\/886"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,5,13]]},"references-count":22,"journal-issue":{"issue":"10","published-online":{"date-parts":[[2026,5]]}},"alternative-id":["cells15100886"],"URL":"https:\/\/doi.org\/10.3390\/cells15100886","relation":{},"ISSN":["2073-4409"],"issn-type":[{"value":"2073-4409","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,5,13]]}}}