Comparison of the Acute Inflammatory Response of Two Commercial Platelet-Rich Plasma Systems in Healthy Rabbit Tendons

Abstract

Background: Numerous studies have shown platelet-rich plasma (PRP) preparations differ with respect to the inclusion of certain blood components, which may affect the host’s cellular response. Hypothesis: This study evaluated the inflammatory effect of Biomet GPS III leukocyte-rich PRP (LR-PRP) versus MTF Cascade leukocyte-poor PRP (LP-PRP) after intratendinous injection in an animal model. The authors anticipated that LR-PRP would incite a greater acute inflammatory response than LP-PRP. Study Design: Controlled laboratory study. Methods: A total of 17 skeletally mature New Zealand White rabbits were tested. In all cases, healthy patellar tendons were treated. In the control animals, one patellar tendon was injected with 2 mL autologous whole blood, and the other was injected with 2 mL sterile saline. Seven total tendons were injected with whole blood, and 7 tendons were injected with saline. In the experimental animals, one patellar tendon was injected with 2 mL LR-PRP, and the other was injected with 2 mL LP-PRP. Ten tendons were injected with LR-PRP, and 10 tendons were injected with LP-PRP. Animals were euthanized at 5 or 14 days after injection. Tendons were harvested and stained using hematoxylin and eosin and scored semi-quantitatively for total white blood cells (WBCs), mononuclear cells (macrophages and lymphocytes), polymorphonuclear cells (PMNs), vascularity, fiber structure, and fibrosis. Results: At 5 days after injection, tendons treated with LR-PRP had significantly greater overall tendon scores (6.3 ± 1.79 vs 1.8 ± 1.64, P = .012), as well as mean scores for fiber structure (1.4 ± 0.22 vs 0.50 ± 0.50, P = .012), denoting disrupted composition, total WBCs (1.1 ± 0.89 vs 0.10 ± 0.22, P = .014), mononuclear cells (macrophages and lymphocytes) (0.80 ± 0.45 vs 0.10 ± 0.22, P = .014), vascularity (1.7 ± 0.27 vs 0.80 ± 0.16, P = .008), and fibrosis (1.0 ± 0.35 vs 0.3 ± 0.45, P = .037) compared with tendons treated with LP-PRP. Otherwise, there were no significant differences in mononuclear cells ( P = .590), PMN cells ( P = 1.00), total WBCs ( P = .811), vascularity ( P = .650), or total tendon score ( P = .596) in any of the treatment groups at 14 days. Conclusion: Compared with leukocyte-poor Cascade PRP, leukocyte-rich GPS III PRP causes a significantly greater acute inflammatory response at 5 days after injection. There is no significant difference in the inflammatory response or cellularity regardless of the injection type at 14 days after intratendinous injection. Clinical Relevance: Platelet-rich plasma injections are frequently prepared using commercial systems and are administered for clinical treatment of chronic tendinopathy. It is important to characterize the cellular responses elucidated by different injection preparations to further understand their effect on tissue healing and aid clinical decision making. Future investigations are necessary to apply these findings to the clinical setting.

Leukocyte-Poor Platelet-Rich Plasma versus Bupivacaine for Recalcitrant Lateral Epicondylar Tendinopathy

“…7,[9][10][11]14 Nonetheless, leukocyte-rich PRP may produce local inflammatory reactions. 10,11,[15][16][17] At one year, improvement in pain was greater after leukocyte-poor PRP injection than bupivacaine, corticosteroid, autologous blood, or leukocyte-rich PRP injection (Table 3). 7,[9][10][11]17 In our study, none of the patients who received leukocytepoor PRP complained of an increased post-injection pain.…”

Quantificação de fatores de crescimento na pele de equinos tratada com plasma rico em plaquetas

“…O que se sabe até o momento é que cada metodologia pode produzir um produto diferente, possivelmente com distintos potenciais terapêu-ticos (Ehrenfest et al 2009), e com variada quantidade e cinética de liberação dos fatores de crescimentos (Ehrenfest et al 2009, Mazzucco et al 2009, Sánchez et al 2009). Levando em consideração as definições básicas para esses componentes ricos em plaquetas, pode-se dizer que no presente estudo foi utilizado um PRP pobre em leucócitos (PRP-PL), o qual pode resultar, quando comparado com o PRP rico em leucócitos (PRP-RL), em menor resposta inflamatória aguda, menor celularidade e vascularização, conforme relatado por Dragoo et al (2012) cinco dias após tratamento de tendões de ratos com PRP-PL ou PRP-RL. De acordo com Wasterlain et al (2012), devido a dificuldade em separar os leucócitos das plaquetas durante a maioria dos protocolos adotados, não é raro se utilizar um PRP-RL, que não é adequado quando se deseja uma menor reação inflamatória.…”

PRP: review of the current evidence for musculoskeletal conditions

“…Dragoo et al [21] showed that leukocyte-rich PRP had a greater inflammatory response relative to leukocyte-poor PRP at post-injection day 5, but there was no difference at day 14. McCarrel et al [22] demonstrated that leukocytereduced PRP had decreased levels of tumor necrosis factor alpha and interleukin 1 beta relative to standard PRP, highconcentration PRP, and concentrated-leukocyte PRP.…”