Evaluating the Effects of Platelet-Rich Plasma and Amniotic Viscous Fluid on Inflammatory Markers in a Human Coculture Model for Osteoarthritis

The Effect of Platelet-Rich Plasma on Synovial Fibrosis and Cartilage Degeneration in Knee Osteoarthritis

BACKGROUND

Synovial fibrosis is a prevalent pathological feature of osteoarthritis and a primary contributor to joint pain and stiffness. Studies indicate that platelet-rich plasma (PRP) is rich in growth factors and cytokines, exhibiting anti-inflammatory, anti-apoptotic, chemotactic, and proliferative properties that can facilitate tissue repair. However, little is known about its effect on synovial fibrosis in knee osteoarthritis (KOA).

PURPOSE

To determine the effect of PRP on synovial fibrosis and cartilage degeneration in KOA.

STUDY DESIGN

Controlled laboratory study.

METHOD

Anterior cruciate ligament transection was performed to induce KOA in male Sprague-Dawley rats, and then rats were randomly assigned to 4 different groups: sham operation, KOA only, KOA treated with phosphate-buffered saline (PBS), and KOA treated with PRP. Synovial collagen fiber deposition was observed using Masson and Sirius red staining, and synovial inflammation was assessed using hematoxylin and eosin (H&E) staining. Moreover, immunohistochemistry was conducted to analyze the expression of synovial fibrosis-related factors including PLOD2, COL1A1, TIMP1, TGF-β1, and α-SMA. KOA severity and articular cartilage degradation were assessed using micro-computed tomography (micro-CT), safranin O-fast green staining, H&E staining, immunohistochemistry, and the Osteoarthritis Research Society International (OARSI) criteria. A quantitative analysis of growth factors (platelet-derived growth factor, IGF-1, epidermal growth factor, TGF-β1, fibroblast growth factor, and endothelial growth factor) in activated PRP was performed using enzyme-linked immunosorbent assay.

RESULTS

Micro-CT imaging and histological staining showed that the KOA model had been successfully established. Compared with the KOA and PBS groups, Masson staining and Sirius red staining results showed that PRP aggravated the degree of synovial fibrosis, which was consistent with the results of immunohistochemistry analysis. Immunohistochemistry analysis showed that PRP promoted the protein expression of PLOD2, COL1A1, TIMP1, TGF-β1, and α-SMA, indicating that the degree of fibrosis was aggravated. However, the PRP group showed lower OARSI and synovitis scores, as well as attenuated abnormal tibial subchondral bone remodeling, suggesting that PRP inhibited further cartilage degeneration and synovial inflammation and improved the subchondral bone microarchitecture.

CONCLUSION

PRP may aggravate KOA synovial fibrosis, but it still has an inhibitory effect on cartilage degeneration and abnormal subchondral bone remodeling.

CLINICAL RELEVANCE

Synovial fibrosis is a significant pathological feature in KOA that is closely linked to clinical symptoms like joint pain and stiffness. This study offers insights into enhancing the effectiveness of PRP therapy for patients with KOA.

Proteomic Characterization of Cardioprotective Human Acellular Amniotic Fluid

Amniotic fluid-derived products are a promising resource for cell therapy and tissue engineering due to their anti-inflammatory, angiogenic, and antifibrotic properties. Human amniotic fluid (hAF) has been used in medical applications such as wound healing, skin disorders, and ophthalmic conditions. Recently, we demonstrated that hAF is an effective treatment for myocardial ischemia-reperfusion injury in adult rats. However, the protein composition of full-term acellular hAF has remained poorly characterized. To uncover the biologically active components underlying hAF's cardioprotective effects, we conducted a global proteomic analysis of hAF collected from six patients at full-term cesarean sections. Previously shown to improve cardiac function in ischemic rats, these samples were analyzed by using tandem mass spectrometry. We identified 657 proteins, including 148 unique to the deep learning platform Inferys. Bioinformatic analysis revealed that these proteins are involved in immunity, inflammatory responses, cell adhesion, and apoptotic signaling pathways. In addition, these proteins were highly modified, with methylation and deamidation being the most abundant modifications. This study represents the first mass-spectrometry-based characterization of full-term, acellular hAF, suggesting that hAF offers a wide array of immune-modulating proteins working together to provide robust cardioprotection and a valuable treatment for ischemia-reperfusion injury.

Mechanisms and applications of the regenerative capacity of platelets-based therapy in knee osteoarthritis

Osteoarthritis (OA) is the most prevalent joint disease in the elderly population and its substantial morbidity and disability impose a heavy economic burden on patients and society. Knee osteoarthritis (KOA) is the most common subtype of OA, which is characterized by damage to progressive articular cartilage, synovitis, and subchondral bone sclerosis. Most current treatments for OA are palliative, primarily aim at symptom management, and do not prevent the progression of the disease or restore degraded cartilage. The activation of α-granules in platelets releases various growth factors that are involved in multiple stages of tissue repair, suggesting potential for disease modification. In recent years, platelet-based therapies, such as platelet-rich plasma, platelet-rich fibrin, and platelet lysates, have emerged as promising regenerative treatments for KOA, but their related effects and mechanisms are still unclear. Therefore, this review aims to summarize the biological characteristics and functions of platelets, classify the products of platelet-based therapy and related preparation methods. Moreover, we summarize the basic research of platelet-based regeneration strategies for KOA and discuss the cellular effects and molecular mechanisms. Further, we describe the general clinical application of platelet-based therapy in the treatment of KOA and the results of the meta-analysis of randomized controlled trials.

Placenta-Derived Products Demonstrate Good Safety Profile and Overall Satisfactory Outcomes for Treating Knee Osteoarthritis: A Systematic Review of Clinical Evidence

PURPOSE

To summarize the available evidence regarding the clinical application of placenta-derived products to treat knee osteoarthritis (OA), underlining the differences existing among products, their preparation methods, and the clinical results reported so far.

METHODS

A research on PubMed, Cochrane, and Google Scholar databases was performed. The following inclusion criteria for relevant articles were used: (1) randomized controlled trials (RCTs), prospective and retrospective studies, on humans; (2) written in English; (3) published in indexed journals in the last 10 years (2011-2022); and (4) dealing with the use of placenta-derived products for the treatment of knee OA. Exclusion criteria were articles written in other languages; animals or in vitro trials; reviews; and trials analyzing other applications of placenta-derived products not related to knee OA.

RESULTS

In total, 16 studies were included in the present systematic review. Five studies investigated placenta-derived products as an augmentation during surgical procedures, whereas 11 studies were focused on the injective approach only. Of these, only 4 were RCTs and were all from the injective approach group. Potential risk of bias was carried out using Cochrane Risk of Bias 2 tool for RCTs and a modified Coleman approach for nonrandomized studies, revealing for both an overall insufficient quality. Clinical outcomes reveal excellent safety profile and notable efficacy, despite the different types of products used and different administration methods adopted.

CONCLUSIONS

Placental products showed a good safety profile and overall satisfactory outcomes for the treatment of knee OA.

LEVEL OF EVIDENCE

Level IV, systematic review of Level II, III and IV studies.

Plantar fasciitis: a comparison of ultrasound-guided fasciotomy with or without amniotic membrane allograft injection

Aim: The purpose of this study was to evaluate the clinical response to augmenting an ultrasound-guided percutaneous plantar fasciotomy (UGPF) with an amniotic membrane (AM) allograft injection. Design: Retrospective, single-center, matched, case-controlled study. Methods: Patients underwent either an UGPF (n = 15) or a combined UGPF and AM injection (n = 16). Results: The UGPF plus AM group demonstrated a significant reduction in pain (p = 0.02) from baseline at the short-term follow-up, but there was no significant difference in pain or patient satisfaction between groups at the 52-week follow-up. Conclusion: Both groups demonstrated a significant reduction in pain and high level of patient satisfaction, but the combination of UGPF with an AM injection may provide a greater reduction in pain earlier in the post-operative period.

The Added Value of the “Co” in Co-Culture Systems in Research on Osteoarthritis Pathology and Treatment Development

Osteoarthritis (OA) is a highly prevalent disease and a major health burden. Its development and progression are influenced by factors such as age, obesity or joint overuse. As a whole organ disease OA affects not only cartilage, bone and synovium but also ligaments, fatty or nervous tissue surrounding the joint. These joint tissues interact with each other and understanding this interaction is important in developing novel treatments. To incorporate and study these interactions in OA research, several co-culture models have evolved. They combine two or more cell types or tissues and investigate the influence of amongst others inflammatory or degenerative stimuli seen in OA. This review focuses on co-cultures and the differential processes occurring in a given tissue or cell as a consequence of being combined with another joint cell type or tissue, and/or the extent to which a co-culture mimics the in vivo processes. Most co-culture models depart from synovial lining and cartilage culture, but also fat pad and bone have been included. Not all of the models appear to reflect the postulated in vivo OA pathophysiology, although some of the discrepancies may indicate current assumptions on this process are not entirely valid. Systematic analysis of the mutual influence the separate compartments in a given model exert on each other and validation against in vivo or ex vivo observation is still largely lacking and would increase their added value as in vitro OA models.

Acellular human amniotic fluid protects the ischemic/reperfused rat myocardium

Amniotic products are potent immunomodulators utilized clinically to repair tissue injury. Little information exists regarding the potential of cell-free human amniotic fluid (hAF) to treat cardiovascular disease. Herein, we sought to determine the influence and efficacy of acellular hAF on myocardial ischemia/reperfusion injury. Processed hAF was obtained from volunteer donors at the time of elective caesarean section and manufactured using proprietary methods. Left anterior descending coronary artery ligation was performed on rats for 60 minutes. Thirty minutes after release and reperfusion, either saline or hAF was injected intramyocardially. Serial echocardiography revealed that compared to saline injected rats, hAF animals maintained their ejection fraction and did not adversely remodel through the 4-week period. This preserved ventricular function correlated with decreased infarct size, less fibrosis, and reduced expression of cytokines and infiltrating inflammatory cells. Comparative arrays of different donor hAF lots confirmed the presence of a wide array of immunomodulatory and host-defense proteins. The observed functional cardioprotection was furthermore evident when given intravenously and across multiple hAF donors. In conclusion, our data demonstrate, for the first time, the cardioprotective effect of acellular hAF on myocardial injury. These observations spanned across diverse donors and likely result from the mixture of a plethora of naturally produced cytokines, chemokines, and immune-modulating proteins rather than a single, defined mechanistic culprit. The ubiquitous availability of hAF as a cell-free solution further suggests its potential for widespread adoption as a therapy for myocardial ischemia/reperfusion injury.

A pilot trial of human amniotic fluid for the treatment of COVID-19

OBJECTIVE

Vertical transmission from SARS CoV-2-infected women is uncommon and coronavirus has not been detected in amniotic fluid. Human amniotic products have a broad immune-mediating profile. Observing that many COVID-19 patients have a profound inflammatory response to the virus, we sought to determine the influence of human amniotic fluid (hAF) on hospitalized patients with COVID-19.

RESULTS

A 10-patient case series was IRB-approved to study the impact of hAF on hospitalized patients with documented COVID-19. Nine of the 10 patients survived to discharge, with one patient succumbing to the disease when enrolled on maximal ventilatory support and severe hypoxia. The study design was altered by the IRB such that the last 6 patients received higher dose of intravenous hAF. In this latter group, patients that had observed reductions in C-reactive protein were associated with improved clinical outcomes. No hAF-related adverse events were noted. Acknowledging some of the inherent limitations of this case series, these results inform and catalyze a larger scaled randomized prospective trial to further investigate hAF as a therapy for COVID-19. Trial Registration ClinicalTrials.gov: NCT04319731; March 23, 2020.

Editorial Commentary: Could Biological Treatments Be the Game-Changing Factor for Osteoarthritis?

The realization of the presence of an inflammatory component in cartilage degeneration together with the promising application of platelet-rich plasma and amnion as "healing agents" opened a new window of opportunity for biological treatments in osteoarthritis. If the goal is to delay or even cease the degenerative process, then treating the cause rather than the symptom is a key factor for this biological intervention to be successful. As new biological agents arise, there are 3 crucial milestones that need to be met in laboratory and clinical studies: safety, reasonable cost, and improved effectiveness in comparison with alternatives.