The Use of Autologous Protein Solution (Pro-Stride®) and Leukocyte-Rich Platelet-Rich Plasma (Restigen®) in Canine Medicine

The effect of two platelet-rich plasma aspiration techniques on plasma cellular concentrations using a double syringe gravitational centrifugation system

OBJECTIVE

To identify which aspiration technique increased plasma platelet concentration and which technique minimized plasma leukocyte and erythrocyte concentrations using a gravitational double-syringe platelet rich plasma (PRP) system.

STUDY DESIGN

Controlled laboratory study.

ANIMALS

Thirty adult dogs.

METHODS

Whole blood was collected into two autologous conditioned plasma (ACP) syringes and an ethylenediaminetetraacetic acid (EDTA tube) (control samples). The ACP syringes were centrifuged for 5 min at 1500 rpm. The proximal 2 mL of plasma from one ACP syringe was deposited in an EDTA tube (preflash samples). Plasma from the second ACP syringe was withdrawn until the buffy coat was pierced, producing a "flash" of red blood cells, agitated and deposited into an EDTA tube (flash samples). Complete blood counts were performed.

RESULTS

Mean plasma platelet concentrations of the control, preflash, and flash samples were 2.4 × 105/dL, 3.3 × 105/dL and 4.1 × 105/dL, respectively. The mean platelet concentration of the flash samples was 7.9 × 104/dL higher than the preflash samples (p = .005). The mean platelet concentration was lower in the control samples than the preflash (p = .002) and flash (p < .0001) samples. The median plasma leukocyte concentration of the preflash samples (0/dL) was lower than in the flash samples (2.4 × 103/dL) (p = .001). The median plasma hematocrit value of the preflash samples (0%) was lower than in the flash samples (1.0%) (p = .002).

CONCLUSION

The flash method is not necessary to produce a PRP sample.

CLINICAL SIGNIFICANCE

Both methods produced PRP. However, clinicians should avoid aspirating the buffy coat when processing PRP for therapies where leukocytes and erythrocytes are contraindicated.

Advances and prospects of platelet-rich plasma therapy in veterinary ophthalmology

In the recent decades, there has been a significant uptick on the use of platelet-rich plasma (PRP) as a better alternative for ophthalmologic therapies in pathologies, primarily of the ocular surface. PRP is a class of liquid platelet concentrate containing a supra-physiological concentration of platelets in a relatively small amount of plasma. Its potential to heal various tissues has piqued interest in its therapeutic application as a biomaterial in regenerative medicine. It is currently a popular therapeutic agent in plastic surgery, cardiothoracic surgery, reconstructive surgery, and even oral and maxillofacial surgery. Based on the data from in vitro and in vivo studies, it can be concluded that PRP possesses adequate therapeutic potential in ocular pathologies, especially those involving cornea. In addition, the high concentrations of growth factors (TGF-β, VEGF, EGF) present in the PRP accelerate the healing of the corneal epithelium. PRP has great therapeutic prospects in veterinary ophthalmology as a regenerative therapeutic modality. However, several variables are yet to be defined and standardized that can directly affect the efficacy of PRP application in different ophthalmic conditions. There is a shortage of research on the use of PRP in ocular surface defects compared to the number of studies and reports on the use of autologous and allogeneic serum eye drops. Therefore, a data-driven approach is required to generate consensus/guidelines for the preparation, characterization, and therapeutic use of PRP in veterinary ophthalmology. This review aims to inform readers of the latest research on PRP, including its preparation methods, physiological and biochemical properties, clinical applications in veterinary ophthalmology, and their safety and efficacy.

Current State of Platelet-rich Plasma in the Treatment of Rheumatic Disease: A Retrospective Review of the Literature

INTRODUCTION

Rheumatic diseases are a spectrum of autoimmune or inflammatory diseases that cause damage to the musculoskeletal system as well as vital organs, such as the heart, lungs, kidneys, and central nervous system.

METHODS

The study of rheumatic disease has made great progress in the understanding and management of these conditions in the last few decades using disease-modifying antirheumatic drugs and synthesized biological immunomodulating therapies. However, one potential treatment that has not been well investigated in rheumatic disease is platelet-rich plasma (PRP). PRP is proposed to facilitate the healing of injured tendons and ligaments through a variety of mechanisms, including mitogenesis, angiogenesis and macrophage activation via cytokine release, although its exact mechanism is unclear.

RESULT

There has been a great deal of work in determining the exact preparation method and composition of PRP for regenerative purposes in orthopedic surgery, sports medicine, dentistry, cardiac surgery, pediatric surgery, gynecology, urology, plastic surgery, ophthalmology, and dermatology. Despite this, there is a paucity of research on the impact of PRP on rheumatic disease.

CONCLUSION

This study aims to summarize and evaluate the current research concerning the use of PRP in rheumatic disease.

Leukocyte and Platelet-Rich Plasma (L-PRP) in Tendon Models: A Systematic Review and Meta-Analysis of in vivo/in vitro Studies

Purpose

To perform a systematic review on the application of leukocyte- and platelet-rich plasma (L-PRP) in tendon models by reviewing in vivo/in vitro studies.

Methods

The searches were performed via electronic databases including PubMed, Embase, and Cochrane Library up to September 2022 using the following keywords: ((tenocytes OR tendon OR tendinitis OR tendinosis OR tendinopathy OR tendon injury) AND (platelet-rich plasma OR PRP OR autologous conditioned plasma OR leukocyte- and platelet-rich plasma OR L-PRP OR leukocyte-richplatelet-rich plasma Lr-PRP)). Only in vitro and in vivo studies that assessed the potential effects of L-PRP on tendons and/or tenocytes are included in this study. Description of PRP, study design and methods, outcomes measured, and results are extracted from the data.

Results

A total of 17 studies (8 in vitro studies and 9 in vivo studies) are included. Thirteen studies (76%) reported leukocyte concentrations of L-PRP. Four studies (24%) reported the commercial kits. In in vitro studies, L-PRP demonstrated increased cell proliferation, cell migration, collagen synthesis, accelerated inflammation, and catabolic response in the short term. In addition, most in vivo studies indicated increased collagen type I content. According to in vivo studies reporting data, L-PRP reduced inflammation response in 71.0% of studies, while it enhanced the histological quality of tendons in 67.0% of studies. All 3 studies reporting data found increased biomechanical properties with L-PRP treatment.

Conclusions

Most evidence indicates that L-PRP has some potential effects on tendon healing compared to control. However, it appears that L-PRP works depending on the biological status of the damaged tendon. At an early stage, L-PRP may accelerate tendon healing, but at a later stage, it could be detrimental.

Proposed Canadian Consensus Guidelines on Osteoarthritis Treatment Based on OA-COAST Stages 1–4

The Canadian consensus guidelines on OA treatment were created from a diverse group of experts, with a strong clinical and/or academic background in treating OA in dogs. The document is a summary of the treatment recommendations made by the group, with treatments being divided into either a core or secondary recommendation. Each treatment or modality is then summarized in the context of available research based support and clinical experience, as the treatment of OA continues to be a multimodal and commonly a multidisciplinary as well as individualized approach. The guidelines aim to help clinicians by providing clear and clinically relevant information about treatment options based on COAST defined OA stages 1–4.

Therapeutic Potential of Platelet-Rich Plasma in Canine Medicine

Platelets are the reservoir of growth factors and play a major role in several physiological processes, such as coagulation, angiogenesis, immune response, and tissue repair. Platelet concentrates are broadly classified into two groups depending on their fibrin content, namely platelet-rich plasma (PRP) and platelet-rich fibrin (PRF). They are further divided based on their leucocyte contents. The PRP is plasma containing supra-physiological concentrations of the platelets. The growth factors present in the PRP play a crucial role in the promotion of local angiogenesis, regulation of cellular activity, stem cell homing, proliferation and differentiation of different stem cells, and deposition of matrix proteins contributing to tissue regeneration. This review aimed to establish the therapeutic potential of PRP in canine medicine with a particular focus on the applications in ophthalmology, dermatology, and musculoskeletal disorders. A systematic literature review was performed to identify the literature published during the past 20 years (2001-2021) using authentic academic databases, such as PubMed, Science Direct, Google Scholar, and Scopus. In the initial search, 556 articles were identified and based on the specific inclusion and exclusion criteria, 59 articles were selected for further analysis. The clinical efficacy of PRP depends on the number of platelets and the growth factor concentration. The PRP-based biological therapy has broad clinical applications in musculoskeletal pathologies. It is a simple, safe, and cost-effective method that can be used to treat various diseases and disorders in canine practice. For example, PRP is used for managing corneal ulcers, corneal erosion, alkali burn, keratoconjunctivitis sicca, burn wounds, chronic wounds, cutaneous ulcers, acute traumatic bone fractures, tendinopathies, cartilage pathologies, osteoarthritis, and abdominal wall defects either as monotherapy or as an adjunctive therapeutic agent. In addition, PRP is widely used as a carrier of mesenchymal stem cells for transplanting into bone defects. Therefore, allogeneic PRP therapy can be considered a simple, safe, and cost-effective method for the treatment of various diseases and disorders in canine practice. The therapeutic application of PRP in canine medicine is limited in the present study due to the lack of consensus for collection, characterization, and clinical use. Hence, further studies are required to establish the actual worth of PRP-based regenerative strategies in canine medicine.