Biochemische eigenschaften des equinen autologous conditioned Plasma® (ACP)

Abstract

Platelet concentrates (PC) are frequently used as a therapeutic technique in equine orthopaedics. The background of this therapy is the isolation of thrombocytes and their reimplantation into damaged tissues, in order to release their wound healing growth factors (GF). Among others PDGF-BB (platelet-derived growth factor BB) and TGF-β1, (transforming growth factor β1) are the most important GFs for tissue regeneration. To obtain PC, Autologous Conditioned Plasma® (ACP) is a relatively new technique, which is easy to use and straight forward. ACP is compounded by using a patented double-syringe system (ACP® syringe). As it was originally designed for the use in human medicine, optimal centrifugation parameters (duration (min) and rotations per minute (rpm)) have not been established for production of equine ACP yet. To set up centrifugation parameters, blood cell and GF concentrations in ACP were compared to their baseline values in whole blood. In the first part of the study, a haemogram from ten healthy Warmblood horses was performed to get the baseline values of blood cell concentrations. The blood samples for ACP processing were prepared in the ACP® syringes. From all horse included, twelve blood samples were taken to obtain ACP Each of these samples was prepared in one of twelve different variants with different centrifugation parameters (rpm, run time). Following parameters were chosen: 900 (127× g), 1100 (189× g), 1300 (=265× g) and 1500 (352 × g) rpm with a run time of 4, 5 or 6 minutes. In each ACP sample, blood cell concentrations were compared with the baseline values, which were first determined in whole blood. Afterwards the concentrations of PDGF-BB and TGF-β1 of three selected centrifugation combinations (900 rpm × 4 min, 1100 rpm × 5 min and 1300 rpm × 6min) were compared. In the second part of this study, conventional plasma from ten other healthy Warmblood horses was prepared and blood cell concentrations and GF concentrations (TGF-8, and PDGF-BB) determined. These results were compared with those from one selected ACP sample (1100 rpm × 5 min) in order to validate the results of this study.With an increase of duration time and rpm of the centrifugation, a non-significant decrease in TC and leucocyte (LC) concentrations was observed. Erythrocytes (EC) could be eliminated from each plasma sample of the three combinations. The combination 1100 rpm × 5min showed a TC concentration increase of 149% (± 20) or 219G/L (± 61). LC concentration was thereby diminished to 12% (0.79 × 109 cells/L). The concentration of PDGF-BB was 1.58 ng/ml and the concentration of TGF-β1, was 1.40 ng/ml. No significant differences were found between the three selected combinations in regard to their GF concentration. In general view, the relatively mild centrifugation combination 1100 rpm × 5 min showed the best results in terms of TC, LC and GF concentrations compared to the other combinations. TC and GF values in ACP were significantly higher compared with those in conventional plasma (p<0.01). Moreover, TC concentrations in whole blood were significantly lower (p<0.01). According to these results, ACP is a practical and straight forward method to obtain a PC for equine medicine. Based on the TC, LC and GF concentrations, the combination 1100 rpm × 5 min can be recommended for the practical application in horses.