Thermal Oscillation Changes the Liquid-Form Autologous Platelet-Rich Plasma into Paste-Like Form

Chen, Jean-Lon; Cheng, Wei-Jen; Chen, Chih-Chi; Huang, Shu-Chun; Chen, Carl P. C.; Suputtitada, Areerat

doi:https://doi.org/10.1155/2022/6496382

BioMed Research International

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Abstract Introduction Methods Results Discussion Conclusion Data Availability Conflicts of Interest Acknowledgments References Copyright Related Articles

Research Article | Open Access

Volume 2022 | Article ID 6496382 | https://doi.org/10.1155/2022/6496382

Thermal Oscillation Changes the Liquid-Form Autologous Platelet-Rich Plasma into Paste-Like Form

Jean-Lon Chen,¹Wei-Jen Cheng,¹Chih-Chi Chen,¹Shu-Chun Huang,¹Carl P. C. Chen,¹and Areerat Suputtitada²

Academic Editor: Chuan Ye

Received03 Jan 2022

Accepted26 Apr 2022

Published09 May 2022

Abstract

Objectives. The texture of the autologous platelet-rich plasma (PRP) that is used in treating degenerative joint diseases such as knee osteoarthritis (OA) is usually in liquid form. However, the turnover rate of protein metabolism in the knee synovial fluid (SF) is less than one hour. This study examined the feasibility of the thermal oscillation technique in converting the liquid-form PRP into an injectable viscous paste-like PRP that may delay the degradation of PRP and continuously release growth factors in the knee joint for a longer period of time. Methods. This study was conducted in the rehabilitation department of a tertiary hospital. A total of 10 elderly patients with an average age of greater than 65 years and diagnosed with moderate degree of knee OA were recruited. The RegenPRP (RegenLab, Le Mont-sur-Lausanne, Switzerland) test tube chamber was used for PRP generation. A total of 60 milliliters (mL) of blood was drawn from each patient. 10 mL of blood was injected into each PRP test tube chamber. As a result, a total of 6 test tube chambers were obtained and each chamber was centrifuged for 15 minutes. Approximately 5 mL of PRP supernatant (the liquid-form end product) was aspirated and sent for thermal oscillation treatment. Five temperatures were tested: 55, 65, 75, 85, and 95 degrees Celsius. Oscillation was set at 200 revolutions per minute (rpm) for 15 minutes. The enzyme-linked immunosorbent assay (ELISA) was applied in measuring the concentration of platelet-derived growth factor (PDGF) in picogram/milliliter (pg/mL). Repeated measures ANOVA followed by the Bonferroni post hoc test was used to compare the PDGF concentrations between each testing condition. Results. Under 75 degrees Celsius of heating, the resultant paste-like PRP end product had the highest concentration of PDGF in picograms per milliliter (pg/mL) as compared with other heating conditions (). The viscosity of the paste-like PRP was measured to be 70,000 centipoise (cP), which is similar to the viscosity of a toothpaste. The paste-like PRP end product was able to release PDGF continuously for about 14 days, with the highest concentration achieved on the 8^th day with an average of . In nonthermally treated liquid-form PRP sample, the highest number of PRP was observed on the 4^th day with an average value of . Under the heating conditions of 55 and 95 degrees Celsius, the highest concentration of PDGF was observed on the 5^th day ( and , respectively). Under the heating conditions of 65 and 85 degrees Celsius, the highest concentration of PDGF was observed on the 7^th day ( and , respectively). Conclusion. Through thermal oscillation, liquid-form PRP can be converted to paste-like PRP end product with a viscosity similar to that of a toothpaste. The best heating condition was discovered to be 75 degrees Celsius. The paste-like PRP was able to release PDGF continuously for about 2 weeks, with the highest concentration obtained on the 8^th day. The findings in this study suggested that paste-like PRP may be a viable option in treating degenerative knee joint diseases.

1. Introduction

Osteoarthritis (OA) is the most common cause of knee pain seen in an orthopedic or rehabilitation outpatient clinic [1, 2]. In knee OA, chondrocytes continue to produce inflammatory mediators that are constantly released into the synovial fluid, resulting in progressive degeneration of the articular cartilage [3, 4]. Autologous platelet-rich plasma (PRP) has been shown to be more effective than other injection options, such as hyaluronic acid (HA), in treating patients with early stages of knee OA [5]. However, the effect of PRP in treating patients with severe stages of knee OA remains controversial [6]. Numerous growth factors are stored in the platelet α-granules, such as transforming (TGF-β) and platelet-derived growth factors (PDGF). They take active roles in the repair of ligaments, tendons, and articular cartilages [7]. PDGF is a potent growth factor that can be used for cartilage regenerative therapy. It can inhibit the expression of matrix metallopeptidase 9 (MMP-9) and MMP-13 proteins, as well as inhibiting the activation of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) by interleukin-1β (IL-1β). As a result, apoptosis of chondrocyte cells can be prevented, and the degradation of the cartilage extracellular matrix can be inhibited [8].

The turnover rate of synovial fluid (SF) protein metabolism is about 1 hour. Therefore, most of the SF proteins will probably be metabolized or replaced within a few hours. Particles with higher molecular weights, such as high molecular weight HA, can have a turnover rate greater than 10 hours [9, 10]. When high molecular weight HA is injected into the knee joints, these particles may remain undegraded for a longer period of time. As a result, it is logical to think that when the liquid-form PRP is injected into the knee joint, a certain percentage of growth factors may be degraded or absorbed within a short period of time due to the turnover rate. This may explain why PRP injections are not effective in some knee OA patients.

Studies related to the development of viscous PRP in treating degenerative knee joint disorders are limited [6]. There is one study that mentioned the application of high viscous paste form-like PRP in facial rejuvenation. However, heating PRP to a near-boiling temperature of 95 degrees Celsius may denature the function of PDGF, causing the aggregation of platelets and plasma proteins, yielding a highly viscous platelet-poor plasma (PPP) injectant end product. This PPP can be used as a suitable filler in aesthetic medicine but may not have adequate regenerative capability in treating degenerative disorders [11].

The development of a viscous paste-like PRP injectant may be a feasible option in treating knee OA. It is crucial to establish the right preparatory method such as heating the liquid-form PRP to a temperature of less than boiling point to activate the growth factors without denaturing the platelets. At the same time, simultaneous cell aggregation is also induced, producing the viscous paste-like PRP injectable end product. The resultant product is injectable through 21- or even 23-gauge needle, and after thermal oscillation, the vibrant platelets can release growth factor continuously for a certain period of time. Due to increased viscosity, the paste-like PRP injectant can be contained within the knee joint for a longer period of time and not easily degraded by knee turnover, offering improved soft tissue repair. The hypothesis of this study is that through heating and oscillating the liquid-form PRP, the texture can be changed into paste-like form with increased viscosity. The discovery of a suitable thermal oscillation preparatory method that can increase the viscosity of the liquid-form PRP with the capability of releasing PDGF continuously may be a breakthrough in the treatment of degenerative joint diseases.

2. Methods

This study was conducted in the rehabilitation department of a tertiary hospital. A total of 10 elderly patients with an average age of greater than 65 and diagnosed with grade 3 on the Kellgren and Lawrence system (moderate degree of knee OA) for the classification of knee OA were recruited. They were to receive knee intra-articular (IA) PRP injection for the treatment of OA. Blood was drawn from their median cubital veins or cephalic veins for the generation of PRP. Informed consent was obtained from all the participants before participating in this study. This study was approved by the Institutional Reviewer Board (IRB) of Chang Gung Medical Foundation. The IRB number was 202100425A3. All the human research conducted in this study was performed in accordance with the Declaration of Helsinki. Patients taking anticoagulants or with platelet counts less than 150,000 per microliter were excluded from this study. Hematology analysis was done to measure the platelet, neutrophil, lymphocyte, and monocyte counts.

2.1. The PRP Testing Conditions

The RegenPRP (RegenLab, Le Mont-sur-Lausanne, Switzerland) test tube chamber for the storage of platelet concentrate was used for PRP generation. Anticoagulant (sodium citrate) is already included inside the chamber. A total of 60 milliliters (mL) of blood was drawn from each patient. 10 mL of blood was injected into each PRP test tube chamber. As a result, a total of 6 test tube chambers were obtained, and each chamber was centrifuged for 15 minutes. The centrifugation speed was set at centrifugal force (RCF) of according to the manufacturer’s instruction. The RegenPRP test tube chamber yields leukocyte-rich PRP (LR-PRP) with high percentage of mononuclear cell (MNC) recovery [12].

After centrifugation, the test tube was gently shaken for about 10 times. The RegenPRP test tube chamber has a layer of separator gel that can keep the red blood cell and plasma layers separated. The reason for shaking the test tube was for thorough mixing of the supernatant (the liquid-form end product) as the buffy coat (white blood cells and platelets) may be adhered on top of the gel after centrifugation. Approximately 5 mL of PRP supernatant was aspirated and sent for thermal oscillation treatment. A thermal oscillation machine capable of heating the samples under different temperatures and oscillation speeds (revolutions per minute (rpm)) was used (MEDCLUB SCIENTIFIC Co., Ltd., Taiwan) (Figure 1). The design of this oscillation machine was to ensure that airtightness can be achieved when 10 mL syringe was inserted into the well. The thermal oscillation conditions for the liquid-form PRP samples were as follows:

Condition for chamber 1: not thermally treated—the liquid form PRP end product was sent directly for PDGF concentration measurement.

Condition for chamber 2: thermally treated using 55 degrees Celsius and oscillated under 200 rpm for 15 minutes.

Condition for chamber 3: thermally treated using 65 degrees Celsius and oscillated under 200 rpm for 15 minutes.

Condition for chamber 4: thermally treated using 75 degrees Celsius and oscillated under 200 rpm for 15 minutes.

Condition for chamber 5: thermally treated using 85 degrees Celsius and oscillated under 200 rpm for 15 minutes.

Condition for chamber 6: thermally treated using 95 degrees Celsius and oscillated under 200 rpm for 15 minutes.

After thermal oscillation, daily PDGF concentration (in picogram/milliliter (pg/mL)) was measured for a total of 14 days. During the 14 days of PDGF concentration measurements, the thermal oscillated end product was placed in a beaker with a surrounding temperature of 33 degrees Celsius. This is the average temperature inside the human knee joint [13]. A volume of approximately 250 microliter (μL) of PRP end product was obtained on a daily basis for the measurement of PDGF concentrations. PDGF concentrations were calculated using the appropriate ELISA kits (Cloud-Clone Corporation, USA) in accordance with the manufacturer’s instructions [14].

2.2. Statistical Analysis

Data analysis was done using the Statistical Program for Social Sciences (SPSS) (SPSS Inc., Chicago, IL) software. The Kolmogorov-Smirnov test was used to determine whether the data obtained in this study was normally distributed or not. Data were expressed as mean and standard deviations (SD). Repeated measures ANOVA followed by the Bonferroni post hoc test was used to observe whether there were significant differences in PDGF concentrations between each sample treatment condition. value of less than 0.05 was considered statistically significant.

3. Results

After hematology analysis, the average platelet count was measured to be . After centrifugation, platelet count increased by about 1.7 times to . After centrifugation, the average neutrophil count decreased by about 68%. The average lymphocyte and monocyte counts increased by about 68% and 50%, respectively (Table 1).

Result of the Kolmogorov-Smirnov test revealed that the data obtained in the study was normally distributed. When heated to a temperature of 65 degrees Celsius and higher, obvious change in the PRP texture from liquid form into paste-like form would occur (Figure 2). This paste-like PRP end product is injectable using the 23- or 21-gauge needle (Figure 3). At 55 degrees Celsius, the texture of the PRP end product appeared to be semi-liquid.

(a)

(b)

(c)

(d)

(e)

It was discovered that by heating the liquid-form PRP to a temperature of 75 degrees Celsius under the oscillation speed of 200 rpm, the resultant paste-like PRP end product yielded the highest concentration of PDGF in picograms per milliliter (pg/mL) as compared with other heating conditions (, Table 2). The viscosity of the paste-like PRP was measured to be 70,000 centipoise (cP), which is similar to the viscosity of a toothpaste. The paste-like PRP end product was able to release PDGF continuously, and the highest concentration of PDGF was reached on the 8^th day for the 75 degrees Celsius thermal oscillation-treated PRP sample with an average of . In the nonthermally treated liquid-form PRP sample, the highest number of PRP was observed on the 4^th day with an average value of .

The heating condition of 95 degrees Celsius yielded the least PDGF concentrations from day 1 to day 14 as compared with other conditions. On day 14, the 95 degrees Celsius treatment condition revealed the least concentration of PDGF with a value of .

Under the PRP treatment conditions of 55 and 95 degrees Celsius, the highest concentration of PDGF was observed on the 5^th day. PDGF concentrations were measured to be for 55 degrees Celsius and for 95 degrees Celsius. For the heating conditions of 65 and 85 degrees Celsius, the highest concentration of PDGF was observed on the 7^th day. PDGF concentrations were measured to be for 65 degrees Celsius and for 85 degrees Celsius (Figure 4).

4. Discussion

This study was aimed at finding the most suitable PRP thermal oscillation treatment condition that can change the texture of PRP from liquid form to paste-like form and at determining which condition can yield the optimal PDGF concentration. The intention of conducting such a study is to generate an injectable highly viscous PRP end product that is not easily degraded by the SF turnover and can release PDGF continuously in the knee joint for a longer period of time. This study has shown that when heating the liquid-form PRP using the temperatures of 65, 75, 85, and 95 degrees Celsius under 200 revolutions per minute (rpm) for 15 minutes, the texture would change from liquid form into paste-like form. The best heating condition was 75 degrees Celsius, which had the highest concentration of PDGF when compared with other temperatures. The highest concentration of PDGF was measured on the 8^th day of PRP storage.

In a study by Wen et al., it was discovered that most of the platelet growth factor concentrations increased as each day progresses during the 7-day PRP storage period [15]. In this study, 6 blood samples were used for statistical comparisons. Our study further elaborated on this PRP storage concept by recruiting more blood samples () and with PDGF concentrations measured up to a period of 14 days. In this study, the LR-PRP with high percentage of mononuclear cell (MNC) recovery was used (RegenPRP test tube chamber) [12]. There are studies suggesting that LR-PRP may fail to alleviate osteoarthritis symptoms due to its inflammatory effects on the synoviocytes [16]. But there are also reports suggesting that the application of LR-PRP can actually benefit the treatment of knee OA [17]. Monocytes and macrophages play a critical role in the development and progression of knee OA. These innate immune cells participate in guiding vascular remodeling and stimulation of local stem cells. Their phenotypes span a continuum of inflammatory (M1) to proregenerative cells (M2). Evidences have shown that subpopulations of monocytes and macrophages stimulate regeneration over inflammatory functions of myeloid cells [17, 18]. In this study, the LR-PRP test tube chambers revealed significant increase in monocyte count after centrifugation, which may have positive implications in the treatment of knee OA.

The autologous plasma injectant with high viscosity is frequently used as suitable fillers in aesthetic medicine [11]. Some studies have tried to combine PRP with hyaluronic acid to increase the viscosity of the injectant [19]. Thermal treatment can increase the viscosity of plasma as the aggregation of platelets and plasma proteins can be promoted. However, high temperatures (ex/exceeding 95 degrees Celsius) can denature the function of PDGF, yielding a platelet-poor plasma (PPP) injectant end product [20].

Perhaps one may question the necessity of developing the thermal oscillation method as PRP may be activated using other strategies such as the addition of calcium chloride [21, 22]. However, some studies have shown that the application of activators such as calcium chloride may not improve the treatment effectiveness of PRP [23]. Therefore, searching for a method that can improve the effectiveness of PRP is needed in treating soft tissue and degenerative disorders. In this study, we have discovered that by heating the liquid-form PRP samples to a temperature above 55 degrees Celsius under the oscillating speed of 200 rpm for 15 minutes, the viscosity of the liquid-form PRP will start to increase. However, at 55 degrees Celsius, the concentration of PDGF is significantly lower as compared with the heating temperatures of 65, 75, and 85 degrees Celsius. When the liquid-form PRP samples were heated to 75 degrees Celsius, obvious paste-like PRP end product can be observed and has a viscosity similar to that of a toothpaste. Under this thermal oscillation condition, it was discovered that the PRP injectant can remain in its viscous paste-like form in an environmental temperature similar to that of the knee joint for approximately 14 days, releasing PDGF continuously during this period of time (Figure 4). Heating must be simultaneously combined with oscillation. Heating without oscillation may result in uneven distribution of the paste-like texture.

Although continuous release of PDGF was also observed in the liquid-form PRP, it is likely to be metabolized in a short period of time as the SF turnover rate in the knee joint is about 1 hour [9]. When the liquid-form PRP was heated up to 95 degrees Celsius, significant decreases in PDGF concentrations were observed in the paste-like PRP end product as compared with other heating temperatures. PDGF was likely to be denatured during the near-boiling point heating process [24]. However, at the heating temperature of 75 degrees Celsius in which the highest PDGF concentration was obtained, it was unlikely that the growth factors were denatured. A study has suggested that heating up to a temperature of 56 degrees Celsius for a period of 1 hour can actually maintain the biological activity of plasma growth factors on ocular surface cells, reducing complement activity and the concentration of immunoglobulin E (IgE) [25].

In our pilot studies, we have injected paste-like PRP injectants (thermally treated using 75 degrees Celsius) into the knee joints of geriatric patients. The Lequesne index was used for the evaluation of treatment effectiveness [26]. Significant improvements in knee pain and function were observed after the injection, lasting up to a period of 6 months. There were no reported adverse effects except possible pain at the injection sites. However, injection-induced pain subsided within 3 days. The shortcoming in this study was that only PDGF was evaluated due to funding limitations. More growth factors will be evaluated (such as vascular endothelial growth factor (VEGF), fibroblast growth factors (FGF), hepatocyte growth factor (HGF), insulin-like growth factor (IGF), epidermal growth factor (EGF), and transforming growth factor (TGF)) in future studies to examine the effect of thermal oscillation on their concentrations. In future studies, the thermal oscillation sample preparation method will also be applied to patients who are taking medications such as steroids and anticoagulants to see if similar increases in growth factor concentrations can be observed as well. Finding a suitable sample preparatory method that can change the texture of liquid-form PRP into a highly viscous paste-like PRP end product that can continuously release PDGF for several days may be a viable option in treating patients with moderate to severe degrees of degenerative knee joint disorders.

5. Conclusion

In summary, this study discovered the feasible thermal oscillation sample preparatory method that can change the texture of liquid-form platelet-rich plasma into paste-like form, and continuously release platelet-derived growth factor for a longer period of time. Thermal oscillation under 75 degrees Celsius and 200 revolutions per minute for a total of 15 minutes was shown to be the most suitable preparatory condition as compared with other heating temperatures. Under the laboratory environment that mimics the knee joint temperature, it was shown that the paste-like PRP end product was able to remain undegraded up to a period of about 2 weeks. The results obtained in this study may have significant implications in future PRP-related studies for the treatment of degenerative joint disorders.

Data Availability

Data and results of statistical analyses are presented in Tables 1 and 2. Raw data may be shared to the readers upon request.

Conflicts of Interest

The authors declare no conflict of interest.

Acknowledgments

This study was supported by the Research Project Grant of Chang Gung Memorial Hospital at Linkou (CMRPG5L0061) with an IRB number of 202100425A3 to Dr. Carl P.C. Chen. This grant supported the expenses of consumable products such as the purchase of ELISA kits.

References

E. Kon, B. Mandelbaum, R. Buda et al., “Platelet-rich plasma intra-articular injection versus hyaluronic acid viscosupplementation as treatments for cartilage pathology: from early degeneration to osteoarthritis,” Arthroscopy, vol. 27, no. 11, pp. 1490–1501, 2011.
View at: Publisher Site | Google Scholar
S. Yagi and M. Sata, “Rupture of pes anserine bursa in a patient with pes anserine pain syndrome due to osteoarthritis,” The Journal of Medical Investigation, vol. 66, no. 1.2, pp. 211-212, 2019.
View at: Publisher Site | Google Scholar
C. P. C. Chen, J. L. Chen, C. C. Hsu, Y. C. Pei, W. H. Chang, and H. C. Lu, “Injecting autologous platelet rich plasma solely into the knee joint is not adequate in treating geriatric patients with moderate to severe knee osteoarthritis,” Experimental Gerontology, vol. 119, pp. 1–6, 2019.
View at: Publisher Site | Google Scholar
M. A. Greene and R. F. Loeser, “Aging-related inflammation in osteoarthritis,” Osteoarthritis and Cartilage, vol. 23, no. 11, pp. 1966–1971, 2015.
View at: Publisher Site | Google Scholar
A. B. Laudy, E. W. P. Bakker, M. Rekers, and M. H. Moen, “Efficacy of platelet-rich plasma injections in osteoarthritis of the knee: a systematic review and meta-analysis,” British Journal of Sports Medicine, vol. 49, no. 10, pp. 657–672, 2015.
View at: Publisher Site | Google Scholar
C. P. C. Chen, C. C. Hsu, S. C. Huang, M. Y. Lin, J. L. Chen, and S. Y. Lin, “The application of thermal oscillation method to augment the effectiveness of autologous platelet rich plasma in treating elderly patients with knee osteoarthritis,” Experimental Gerontology, vol. 142, article 111120, 2020.
View at: Publisher Site | Google Scholar
A. Khoshbin, T. Leroux, D. Wasserstein et al., “The efficacy of platelet-rich plasma in the treatment of symptomatic knee osteoarthritis: a systematic review with quantitative synthesis,” Arthroscopy, vol. 29, no. 12, pp. 2037–2048, 2013.
View at: Publisher Site | Google Scholar
I. Setiawan, I. K. Suyasa, P. Astawa, I. W. S. Dusak, I. K. S. Kawiyana, and I. G. N. W. Aryana, “Recombinant platelet derived growth factor-BB and hyaluronic acid effect in rat osteoarthritis models,” Journal of Orthopaedics, vol. 16, no. 3, pp. 230–233, 2019.
View at: Publisher Site | Google Scholar
A. Mero, M. Campisi, M. Favero et al., “A hyaluronic acid-salmon calcitonin conjugate for the local treatment of osteoarthritis: chondro-protective effect in a rabbit model of early OA,” Journal of Controlled Release, vol. 187, pp. 30–38, 2014, Epub 2014 May 15.
View at: Publisher Site | Google Scholar
S. L. Myers and K. D. Brandt, “Effects of synovial fluid hyaluronan concentration and molecular size on clearance of protein from the canine knee,” The Journal of Rheumatology, vol. 22, no. 9, pp. 1732–1739, 1995.
View at: Google Scholar
N. N. Doghaim, R. A. El-Tatawy, and Y. M. E. Neinaa, “Assessment of the efficacy and safety of platelet poor plasma gel as autologous dermal filler for facial rejuvenation,” Journal of Cosmetic Dermatology, vol. 18, no. 5, pp. 1271–1279, 2019.
View at: Publisher Site | Google Scholar
J. Magalon, O. Bausset, N. Serratrice et al., “Characterization and comparison of 5 platelet-rich plasma preparations in a single-donor model,” Arthroscopy, vol. 30, no. 5, pp. 629–638, 2014.
View at: Publisher Site | Google Scholar
C. Becher, J. Springer, S. Feil, G. Cerulli, and H. H. Paessler, “Intra-articular temperatures of the knee in sports - an in-vivo study of jogging and alpine skiing,” BMC Musculoskeletal Disorders, vol. 9, no. 1, p. 46, 2008.
View at: Publisher Site | Google Scholar
E. Kurys-Denis, A. Prystupa, D. Luchowska-Kocot, W. Krupski, H. Bis-Wencel, and L. Panasiuk, “PDGF-BB homodimer serum level - a good indicator of the severity of alcoholic liver cirrhosis,” Annals of Agricultural and Environmental Medicine, vol. 27, no. 1, pp. 80–85, 2020, Epub 2020 Jan 25.
View at: Publisher Site | Google Scholar
Y. H. Wen, W. Y. Lin, C. J. Lin et al., “Sustained or higher levels of growth factors in platelet-rich plasma during 7-day storage,” Clinica Chimica Acta, vol. 483, pp. 89–93, 2018.
View at: Publisher Site | Google Scholar
H. J. Braun, H. J. Kim, C. R. Chu, and J. L. Dragoo, “The effect of platelet-rich plasma formulations and blood products on human synoviocytes: implications for intra-articular injury and therapy,” The American Journal of Sports Medicine, vol. 42, no. 5, pp. 1204–1210, 2014, Epub 2014 Mar 14.
View at: Publisher Site | Google Scholar
R. Uchiyama, E. Toyoda, M. Maehara et al., “Effect of platelet-rich plasma on M1/M2 macrophage polarization,” International Journal of Molecular Sciences, vol. 22, no. 5, p. 2336, 2021.
View at: Publisher Site | Google Scholar
M. E. Ogle, C. E. Segar, S. Sridhar, and E. A. Botchwey, “Monocytes and macrophages in tissue repair: implications for immunoregenerative biomaterial design,” Experimental Biology and Medicine (Maywood, N.J.), vol. 241, no. 10, pp. 1084–1097, 2016.
View at: Publisher Site | Google Scholar
F. Russo, M. D’Este, G. Vadalà et al., “Platelet rich plasma and hyaluronic acid blend for the treatment of osteoarthritis: rheological and biological evaluation,” PLoS One, vol. 11, no. 6, article e0157048, 2016.
View at: Publisher Site | Google Scholar
K. Karimi and H. Rockwell, “The benefits of platelet-rich fibrin,” Facial Plastic Surgery Clinics of North America, vol. 27, no. 3, pp. 331–340, 2019.
View at: Publisher Site | Google Scholar
E. Anitua, R. Prado, M. Azkargorta et al., “High-throughput proteomic characterization of plasma rich in growth factors (PRGF–Endoret)-derived fibrin clot interactome,” Journal of Tissue Engineering and Regenerative Medicine, vol. 9, no. 11, pp. E1–12, 2015.
View at: Publisher Site | Google Scholar
C. Cavallo, A. Roffi, B. Grigolo et al., “Platelet-rich plasma: the choice of activation method affects the release of bioactive molecules,” BioMed Research International, vol. 2016, 2016.
View at: Google Scholar
P. Gentile, J. Cole, M. Cole et al., “Evaluation of not-activated and activated PRP in hair loss treatment: role of growth factor and cytokine concentrations obtained by different collection systems,” International Journal of Molecular Sciences, vol. 18, no. 2, p. 408, 2017.
View at: Publisher Site | Google Scholar
X. Wang, H. Wang, D. Wang et al., “Thermal denaturation produced degenerative proteins and interfered with MS for proteins dissolved in lysis buffer in proteomic analysis,” Electrophoresis, vol. 32, no. 3-4, pp. 348–356, 2011.
View at: Publisher Site | Google Scholar
E. Anitua, F. Muruzabal, M. de la Fuente, J. Merayo-Lloves, and G. Orive, “Effects of heat-treatment on plasma rich in growth factors-derived autologous eye drop,” Experimental Eye Research, vol. 119, pp. 27–34, 2014.
View at: Publisher Site | Google Scholar
J. Lecorney, F. Verhoeven, M. Chouk, X. Guillot, C. Prati, and D. Wendling, “Correlation between catastrophizing and Lequesne index in case of osteoarthritis of the knee: a prospective study,” Joint, Bone, Spine, vol. 85, no. 5, pp. 605–607, 2018.
View at: Publisher Site | Google Scholar

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Copyright © 2022 Jean-Lon Chen et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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