Platelet-rich plasma: lyophilization as an alternative for conservation and transport

• Published in: Journal of equine veterinary science 2023-06, Vol.125, p.104748, Article 104748
• Main Authors: Sobral, Gilvannya G, Catão, Eveline de Fátima L, Ribeiro, Danielle P, Xavier, Gabriela R, Pinto, Gustavo O A, Tobal, Lucas F M, Arruda, Lúcia Cristina P, Carneiro, Gustavo F
• Format: Article
• Language: English
• ISSN: 0737-0806; 1542-7412
• DOI: 10.1016/j.jevs.2023.104748

Platelet-rich plasma (PRP) has been used in equine reproduction to improve pregnancy rates due to its immune-modulating effect. Platelet granules contain numerous proteins, such as growth factors, cytokines, and antimicrobial peptides. However, the shelf life of platelets is 5 days and used at a temperature above 20°C, where there is the concern of bacterial contamination. Also, preparation is a time-consuming procedure. Therefore, studies to find an effective method of PRP storage would be of great benefit, saving costs, and could also guarantee a faster and more effective treatment. This work compared the platelet levels between fresh and lyophilized PRP. Peripheral blood from 8 healthy equine males with a mean age of 4±2years was collected in 4.5-mL vacutainer tubes containing 3.2% sodium citrate. The PRP preparation was performed by double centrifugation in vacutainer tubes. Blood was homogenized and centrifuged at 120g for 10 minutes. After the first centrifugation, the upper 30% of the plasma was discarded. The remaining plasma (70%) was submitted to another centrifugation at 240g for 10 minutes. After the second centrifugation, 30% of plasma at the bottom of each tube was considered PRP. Platelet count was carried out with an automated hematology analyzer (HematoClin 2.6VET - Bioclin IL, USA). The lyophilization process was carried out at the Research Support Center of the Federal RuralUniversity of Pernambuco. Before being lyophilized, samples were frozen at -80°C for 24 h and then processed in an Alpha 1-4 LD Plus Christ apparatus, a drying chamber temperature of -27°C and vacuum of 0.52 mbar, for 24 hours. The lyophilized PRP obtained was stored in well-sealed microtubes and kept frozen at -4°C for further analysis. The results were subjected to analysis of variance (ANOVA) to determine the effects of lyophilization on the platelet concentrations. Significance was declared at P