Plasma rich in growth factors (PRGF) technology: simple facts that turn on the lights.

We have read with great interest the article of Giannini et al1 entitled “Comparison between PRP, PRGF and PRF: lights and shadows in three similar but different protocols”. In this article, the authors compare the PRP, PRGF and PRF protocols and products in order to suggest to the clinicians the best blood-derivative product for regenerative surgery. We thank the authors for their contribution in the area of blood-derived biomaterials. However we would like to make some remarks on what was mentioned about PRGF technology in such review. Due to space considerations, only the main ones are commented. First, the correct term is Plasma Rich in Growth Factors (PRGF). We must point out that the PRGF technology uses extraction tubes with 0.9 mL of 3.8% trisodium citrate per 8.1 mL of blood. The appropriate centrifugation speed is 580 g for 8 min at room temperature2. This speed was optimized for more than five years and there are over 30 international articles citing it. We would also like to clarify that in addition to be leukocyte free, PRGF does not contain MSC in their formulations, since it is only composed of platelet-enriched plasma3. Furthermore, the authors state that the PRGF technique uses only a share of 20% of the blood collected (also, the cited reference does not correspond with the text) when the efficiency of this technique (platelet recovery) is greater than 60% (F1 + F2 combination)2 and the average PRGF volume is 40% of the original blood volume. And finally, PRGF complies with all international regulations of the countries where it has been marketed, including those of the European Union4.