Background: Differences in response to PRP (platelet-rich plasma) therapy may be linked to the variability of growth factors and their receptor's genes. Considering that, we checked whether the platelet-derived growth factor receptor beta gene (PDGFRB) single nucleotide polymorphisms (SNPs) affect the effectiveness of PRP therapy in treating tennis elbow patients.
Methods: The treatment efficacy was analyzed over time (2, 4, 8, 12, 24, 52, and 104 weeks after PRP injection) on 107 patients (132 elbows) using PROMs (patient-reported outcome measures), namely VAS (Visual Analog Scale), QDASH (quick version of Disabilities of the Arm, Shoulder, and Hand) and PRTEE (Patient-Rated Tennis Elbow Evaluation). Five polymorphisms of the PDGFRB gene (rs4324662, rs758588, rs3828610, rs3756311, and rs3756312) were genotyped.
Results: The CC (rs3828610) and GG (rs3756311 and rs3756312) genotypes had a particularly strong impact on the effectiveness of the therapy, as measured by the values of PROMs, both in additive as well as dominant/recessive models. These homozygotes were also characterized by significantly higher values of MPV (mean platelet volume).
Conclusions: The PDGFRB gene SNPs affect the effectiveness of PRP therapy in treating tennis elbow patients and it may result from the differentiated metabolic activity of platelets in particular genotype variants.
Keywords: PDGFRB; PRP; SNP; tendinopathy; tennis elbow.