Platelet lysate obtained via plateletpheresis performed in standing and awake equine donors.

This study explores the use of plateletpheresis to extract platelet concentrate from horses, with the aim of aiding tissue healing or as an alternative to animal-based cell culture media. The experiment, which used a commercially available apheresis equipment on chemically restrained horses, showed promising results both in terms of feasible extraction, and the presence of potential growth factors in the platelet lysate.

Overview of the Study Design

• The study was conducted on six female mixed breed horses that were chemically restrained.
• Plateletpheresis, a process usually used in human medicine to collect platelets, was executed on these subjects using commercially available apheresis equipment.
• Physical examinations were performed and blood samples were taken before and after the procedure, and subsequently at 8, 16, 24, and 48 hours after plateletpheresis. This facilitated assessing potential procedural impacts and changes over time.
• The collected platelet concentrate was then subjected to two freeze-thaw cycles, followed by centrifugation and filtration, to produce the platelet lysate.
• The resulting platelet lysate was examined for cellular debris, fibrinogen, and growth factors to further understand its potential utility.

Findings of the Study

• The average platelet yield resulting from the plateletpheresis was 390 × 10 /μL, highlighting the procedure as effective for collecting platelet concentrate from horses.
• There was a decrease in the donor horse’s platelet count after the procedure, from 193 × 10 /μL to 138 × 10 /μL on average. This decrease, however, did not pose a risk of hemorrhage to any of the subjects, suggesting that the procedure is relatively safe.
• The processed platelet lysate showed minimal cellular residue and contained growth factor concentrations at 6.1 ng/mL for transforming growth factor-β1, 3.5 ng/mL for platelet-derived growth factor-BB, and 13.8 ng/mL for vascular endothelial growth factor-A.

Significance and Impact

• As the platelet lysate contained relevant growth factors, it presents potential for use as a fetal bovine serum (FBS) substitute in cell culture. This could be an important alternative to traditional methods which could face ethical scrutiny or practical limitations.
• The study also validates plateletpheresis as a viable method for collecting platelet concentrate from equine donors, which could enhance the healing of injured tissues, particularly in the field of veterinary medicine.