Platelet lysates from aged donors promote human tenocyte proliferation and migration in a concentration-dependent manner

Abstract

ObjectivesPlatelet-rich plasma (PRP) is being used increasingly often in the clinical setting to treat tendon-related pathologies. Yet the optimal PRP preparations to promote tendon healing in different patient populations are poorly defined. Here, we sought to determine whether increasing the concentration of platelet-derived proteins within a derivative of PRP, platelet lysate (PL), enhances tenocyte proliferation and migration in vitro, and whether the mitogenic properties of PL change with donor age.MethodsConcentrated PLs from both young (< 50 years) and aged (> 50 years) donors were prepared by exposing pooled PRP to a series of freeze-thaw cycles followed by dilution in plasma, and the levels of several platelet-derived proteins were measured using multiplex immunoassay technology. Human tenocytes were cultured with PLs to simulate a clinically relevant PRP treatment range, and cell growth and migration were assessed using DNA quantitation and gap closure assays, respectively.ResultsPlatelet-derived protein levels increased alongside higher PL concentrations, and PLs from both age groups improved tenocyte proliferation relative to control conditions. However, PLs from aged donors yielded a dose-response relationship in tenocyte behaviour, with higher PL concentrations resulting in increased tenocyte proliferation and migration. Conversely, no significant differences in tenocyte behaviour were detected when increasing the concentration of PLs from younger donors.ConclusionHigher PL concentrations, when prepared from the PRP of aged but not young donors, were more effective than lower PL concentrations at promoting tenocyte proliferation and migration in vitro.Cite this article: D. R. Berger, C. J. Centeno, N. J. Steinmetz. Platelet lysates from aged donors promote human tenocyte proliferation and migration in a concentration-dependent manner. Bone Joint Res 2019;8:32–40. DOI: 10.1302/2046-3758.81.BJR-2018-0164.R1.

The optimal platelet concentration in platelet-rich plasma for proliferation of human cells in vitro—diversity, biases, and possible basic experimental principles for further research in the field: A review

“…Similar results found by Rughetti et al (2008). Anitua et al (2009) and Berger et al (2019), on the other hand, used a PRP volume of 20% and found maximum proliferation rate at 0.767 ± .95 and 0.875 (young group) x 10 6 plt/µL, respectively-about half of Haynesworth et al (2002) and Wang et al (2019). Graziani et al (2006) used the highest PRP/media ratio (33%/67%) and observed maximum proliferation of approx.…”

“…. '' Low ACD CaCl 2 10% of 2.94+/-1.9 × 10 6 2.94+/-1.9 × 10 6 0.875 × 10 6 Berger et al (2019) Leukocyte level: mean 0.1 × 10 3 /µ L (SD 0.1) (Supplementary material) Low CPD Freeze-and-thaw 20% of 0.875 × 10 6 (Young group) 20% of 3.5 × 10 6 (Old group) 3.5 × 10 6 Wang et al (2012) Leukocyte level: 0.37 ± 0.14 ×10 9 /L Leukocyte concentration in PRP significantly lower than that in whole blood (P < 0.001). ( See article Mean optimal PRP concentration 2.7 × 10 6 optimal concentration, respectively.…”

“…Still, three studies observed an increased synthesis of collagen type I and/or II or HA (Anitua et al, 2009;Jo et al, 2012;Wang et al, 2012). Four studies observed increased cell motility and invasion at moderate (Berger et al, 2019;Giusti et al, 2014;Graziani et al, 2006) or relatively high concentration (Rughetti et al, 2008).…”

“…Yes 5% of 1.194 × 10 6 Not tested Not tested 20% of 0.875 × 10 6 (Young group) Berger et al (2019) Platelet lysate corresponding to platelet levels of 14x, 7x, 3.5x, 1.75x and 0.9x of WB Fibroblasts (Achilles, patellar, and palmaris) Yes 20% of 3.5 × 10 6 (Old group) ______ Old group: 3.5 × 10 6 Not tested Wang et al (2019) Platelet lysate corresponding to 0.2 ×10 6 , 0.5 ×10 6 , 0.8 ×10 6 , 1.0 ×10 6 , 1.2 ×10 6 , 1.5 ×10 6 , 2.0 ×10 6 , 2.7 ×10 6 , and 3.0 ×10 6 HMSC (bone marrow) Yes 10% of 1.5 to 3.0 × 10 6 Not tested (Cell differentiation)…”

“…However, no clear tendencies or pattern is seen regarding different activation methods and the optimal PRP concentration (Tables 5 and 6). Berger et al (2019) divided the blood donors in a ''young group'' (mean age 27 ±5) and an ''old group'' (mean age of 63 ±11) and observed an age-dependent optimal PRP concentration, 20% of 0.875 ×10 6 and 3.5 x 10 µ plt/µL, respectively. These findings are comparable with Anitua et al (2009) who used the same PRP volume (20%), cell type (fibroblasts), and blood donors characterized as ''young'' ( Table 7).…”