A recent study examined the possibility of preserving platelet-rich plasma (PRP) for future applications, with the same biological effectiveness. The study aimed to exam such effectiveness by comparing matrix metalloproteinases (MMP) isoform concentrations between different blood preparations: whole blood (WB), leukocyte-rich PRP (LR-PRP) inactivated (LR-I) and activated (LR-A), and leukocyte-poor PRP (LP-PRP) inactivated (LP-I) and activated (LP-A).
Blood samples were obtained from 24 patients and were either immediately assayed and analyzed (fresh) or stored at -80℃ for 24 hours, 72 hours, and 160 hours.
The study showed the following changes in MMP isoform concentrations:
- MMP-1 significantly increased between fresh and 160 hours in WB, and significantly increased between fresh and 24 hours and 160 hours in LR-A
- MMP-3 significantly decreased between fresh and 24 hours, 72 hours, and 160 hours in LR-A.
- MMP-9 significantly increased between fresh and 160 hours in WB, LR-A, and LR-I.
- MMP-12 significantly decreased between fresh and 24 hours in LR-A , while MMP-12 significantly decreased between fresh and 24 hours, 72 hours, and 160 hours in WB, LR-I, and LP-I.
- MMP-10 was not statistically different amongst fresh and freezing time points in all WB and PRP preparations
The results of the study suggest that certain MMP isoforms can either increase or decrease in response to freezing in WB, inactivated PRP, and activated PRP formulations. As the science of PRP continues to expand, and we understand the roles of different MMP isoforms, these changes in concentrations based on temperature may bear more clinical significance. More research is needed to better understand the potential of PRP preservation and maintaining biological effectiveness with minimal manipulation.