# How to extract leucocyte‐poor platelet‐rich plasma using a commercial platelet concentration system developed to obtain leucocyte‐rich platelet‐rich plasma: A pilot study

## TL;DR

This study shows how to modify a commercial device to extract platelet-rich plasma with fewer white blood cells.

## Contribution

A new protocol for producing leucocyte-poor PRP using an existing commercial system is proposed and validated.

## Key findings

- Modified protocol significantly reduced leucocyte concentrations by 75.3%.
- Platelet concentration was only reduced by 18.1% using the new protocol.
- The modification does not require additional supplies.

## Abstract

To develop and characterise a modification of the preparation protocol of a commercial leucocyte‐rich platelet‐rich plasma (LR‐PRP) preparation device (the GPS® III Platelet Concentration System, Biomet, USA) that allows for consistent leucocyte‐poor platelet‐rich plasma (LP‐PRP) extraction using the same components.

The study included two stages. In the first, the blood of eight healthy adults was processed using the GPS® III Platelet Concentration System (Biomet, USA). Samples were obtained to characterise platelet and leucocyte distribution in the system during the procedure per the manufacturer′s guidelines. In the second, based on the initial results, the standard preparation protocol that yields LR‐PRP was modified to establish a new protocol for obtaining LP‐PRP. To conclude, the newly proposed procedure was validated in 20 individuals, using both the traditional and modified protocols simultaneously.

The characterisation of the commercial system suggested a specific distribution of blood components within the device: most leucocytes were found in the plasma collected through side port #3 (red cap) without waving or shaking the tube, whereas platelets in the sediment between the buoys were released when the tube was waved or shaken. When comparing to the standard protocol, the modified technique consistently yielded significantly lower platelet (MD −205 ×103 platelets/µL, 95% confidence interval [CI], 92.1–317 ×103 platelets/µL, <0.0001) and leucocyte concentrations (MD −19.0 ×103 leucocytes/µL, 95% CI, 14.1–23.9 ×103 leucocytes/µL, p < 0.0001) but the obtained LP‐PRP had only 18.1% lower platelet concentration (95% CI, 6.71%–29.4%, p < 0.0001) and a relevant 75.3% lower leucocyte concentration (95% CI, 69.6%–81%, p < 0.0001).

The proposed modified PRP extraction protocol greatly reduced leucocyte concentrations with a minimal reduction in the platelet concentrations, enabling LP‐PRP preparation with the same commercial device without the need for additional supplies.

Level III.