An in vitro long-term study of cryopreserved umbilical cord blood-derived platelet-rich plasma containing growth factors-PDGF-BB, TGF-β, and VEGF

Comparative efficacy of intrauterine infusion treatments for recurrent implantation failure: a network meta-analysis of randomized controlled trials

OBJECTIVE

Recurrent implantation failure (RIF) is a significant challenge in assisted reproductive technology (ART), affecting many women undergoing in vitro fertilization (IVF). This study aims to compare the efficacy of various intrauterine infusion treatments, including granulocyte colony-stimulating factor (G-CSF), platelet-rich plasma (PRP), human chorionic gonadotropin (HCG), and peripheral blood mononuclear cells (PBMCs), in improving clinical pregnancy rate (CPR), live birth rate (LBR), and miscarriage rate (MR) in women with RIF.

METHODS

A comprehensive search was conducted in multiple databases, including Cochrane Central Register of Controlled Trials (CENTRAL), PubMed, Embase, Web of Science, and China National Knowledge Internet (CNKI), to identify randomized controlled trials (RCTs) evaluating the efficacy of intrauterine infusion treatments for RIF. Data extraction and quality assessment were performed independently by two reviewers. Network meta-analysis was conducted using a random-effects model to compare the outcomes of different treatments.

RESULTS

A total of 25 RCTs involving 3035 patients were included in the network meta-analysis. The treatments involved G-CSF, PRP, HCG, PBMCs, placebo, and blank control. The results of the network meta-analysis for CPR and LBR were statistically significant among treatments, but there was no statistical significance in MR. The surface under cumulative ranking curve (SUCRA) ranking of CPR and LBR showed that intrauterine infusion treatments of G-CSF, PRP, HCG, and PBMCs were much better than placebo and blank. The SUCRA values of CPR were ranked probabilistically from high to low as follows: PRP (84.5%) > PBMCs (76.5%) > G-CSF (65.7%) > HCG (52.5%) > placebo (20.8%) > blank (0.1%). The SUCRA values of LBR were ranked probabilistically from high to low as follows: PRP (81.4%) > PBMCs (64.6%) > G-CSF (58.0%) > HCG (48.7%) > placebo (42.4%) > blank (4.9%).

CONCLUSION

All these findings confirmed that intrauterine infusions of PRP and PBMCs significantly improve pregnancy outcomes in women with RIF. PRP emerged as the most effective treatment. However, to establish the most effective approach for managing patients with RIF, future research should prioritize direct and robust comparisons between PRP and other therapeutic strategies, ensuring a comprehensive evaluation of their relative efficacy.

Umbilical cord blood-derived platelet-rich plasma as a coating substrate supporting cell adhesion and biological activities of wound healing

BACKGROUND

Platelet-rich plasma (PrP) is a blood derivative with positive roles in regenerative medicine, particularly in wound healing. Evidence has been reported for using peripheral blood-derived PrP in disease treatments, but umbilical cord blood (UCB)-derived PrP remains limited. Thus, we investigate the roles of UCB-derived PrP in cellular behaviours in vitro and in wound healing in vivo models.

METHODS

We used 2D and 3D cell culture models to investigate the role of UCB-derived PrP gels in stimulating the attachment, proliferation, migration, and spheroid formation of umbilical cord-derived mesenchymal stem cell (UCMSC) and human dermal fibroblast (hFB). In addition, immunoassay and PCR were used to understand the enrichment of growth factors in UCB-derived PrP and the change of ECM genes in PrP-treated cells. Finally, a rat model was used to investigate the cutaneous wound healing process.

RESULTS

UCB-derived PrP gels were enriched with platelet-derived growth factor-BB (PDGF-BB) (3394.1 ± 2658.3 pg/mL), vascular endothelial growth factor-A (VEGF-A) (282.0 ± 53.0 pg/mL), hepatocyte growth factor (HFG) (762.7 ± 117.5 pg/mL), and fibroblast growth factor 2 (FGF-2) (17.734 ± 8 pg/mL). In addition, these UCB-derived PrP gels promoted cell attachment (> 154 % and > 117 % for UCMSCs and hFBs, respectively), proliferation (UCMSCs > 121 % and hFBs > 117 % at all time points), migration increased by 27 % and 26 % for UCMSCs and hFBs, and spheroid formation and fusion compared to the control. UCB-derived PrP gels also induced different expression of ECM genes, including COL1, COL3, HAS1, HAS2, HAS3, and ENL, in both UCMSCs and hFBs. Finally, this product from UCBs could enhance the wound healing process in excised skin rat models by reducing the wound area by 80 % compared to 27 % in controls after 14 days.

CONCLUSIONS

UCB-derived PrP gels facilitate cell behaviours in vitro, including cell adhesion, growth, and migration. In addition, in animal models, UCB-derived PrP reduced the wound healing time and enhanced the completion of skin tissues by increasing granulation tissue formation and reducing neutrophils at wound sites. These UCB-derived PrP gels will be used to support spheroid formation that will be used as biomaterials for 3D printing, engraftment, and wound healing treatment.

Application of cord blood-derived platelet-rich plasma in the treatment of diseases

Platelet-rich plasma (PRP), a blood product containing high concentrations of platelets, has been increasingly used for the treatment of a number of diseases because of its anti-inflammatory and regenerative properties. PRP is generally obtained from the patient's own peripheral blood when used in clinical applications, but allogeneic PRP extracted from umbilical cord blood has also attracted attention due to its unique advantages. The main purpose of this narrative review was to summarize the research and clinical application of cord blood-derived PRP (CB-PRP) in the treatment of diseases up to April 2024. This review also discusses the differences between CB-PRP and autologous PRP (A-PRP). A thorough search of PubMed® and Clinicaltrials.gov identified 13 articles and four clinical trials. To date, CB-PRP has been primarily studied in the fields of orthopaedics, dermatology, neurology, obstetrics/gynaecology and ophthalmology. This is likely to be because this research is relatively novel. Considering the differences between the characteristics of A-PRP and CB-PRP, it is thought that CB-PRP might hold more promise for broader applications in the future.

Cord blood platelet rich plasma (PRP) as a potential alternative to autologous PRP for allogenic preparation and regenerative applications

As an abundant supplier of growth factors, chemokines and other bioactive molecules, platelet rich plasma (PRP) become a leading therapy for tissue regeneration. The PRP therapy is an inexpensive and feasible source of growth factor compared to commercial products however, the better source of platelets is the major challenge. Many researchers are skeptical about cord blood as an alternative source for the allogenic preparation of PRP. In the present study, we have compared adult peripheral and cord blood PRP for their regenerative capacity and immuno-modulatory nature. ELISA data indicates that the cord PRP contained a considerably higher amount of growth factors compared to adult PRP. In-vitro results indicate a significant increase in cell proliferation and migration with cord PRP treatment. The immunomodulatory evaluation shows cord blood PRP has better potential in switching activated macrophages to anti-inflammatory markers when compared with adult PRP, as well as the cytokines production indicates a significant reduction in the release of IFN-γ in cord PRP treatment. The study shows the beneficial effects of using cord blood PRP over adult PRP however, future studies are required to validate cord blood PRP as a permanent source for regenerative therapy.

The value of intraovarian autologous platelet rich plasma in women with poor ovarian reserve or ovarian insufficiency: a systematic review and meta-analysis

OBJECTIVES

To assess the value of intraovarian PRP in women with low ovarian reserve.

SEARCH STRATEGY

Screening of databases from inception to January 2023 using the keywords related to "Platelet-rich plasma" AND "poor ovarian reserve" OR "ovarian failure".

SELECTION CRITERIA

Fourteen studies (1632 participants) were included, 10 included women with POR, 1 included women with POI and 3 included both POR and POI women.

DATA COLLECTION AND ANALYSIS

Extracted data included study settings, design, sample size, population characteristics, volume, timing and preparation of PRP administration, and outcome parameters.

MAIN RESULTS

AMH level was evaluated in 11 studies (2099 women). The mean difference (MD) was 0.09 with 95% CI of - 0.06, 0.24 (P = 0.25). Antral follicular count level was assessed in 6 studies (1399 women). The MD was 1.73 with 95% CI of 0.81, 2.66 (P < 0.001). The number of oocytes retrieved was evaluated in 7 studies (1413 women). The MD was 1.21 with 95% CI of 0.48, 1.94 (P = 0.001).

CONCLUSION

This systematic review found a significant improvement of AFC, the number of retrieved oocytes, the number of cleavage embryos and the cancellation rate in women with POR.

TRIAL REGISTRATION

Registration number CRD42022365682.

The value of platelet-rich plasma in women with previous implantation failure: a systematic review and meta-analysis

OBJECTIVE

To assess the value of intrauterine PRP to improve IVF outcome in women with previous implantation failure.

METHODS

Screening of Pubmed, Web of Science, and other databases from inception to August 2022 using the keywords related to "platelet-rich plasma" OR "PRP" AND "IVF" "implantation failure." Twenty-nine studies (3308 participants) were included in our analysis, 13 were RCTs, 6 were prospective cohorts, 4 were prospective single arm, and 6 were retrospective analyses. Extracted data included settings of the study, study type, sample size, participants' characteristics, route, volume, timing of PRP administration, and outcome parameters.

RESULTS

Implantation rate was reported in 6 RCTs (886 participants) and 4 non-RCTs (732 participants). The odds ratio (OR) effect estimate was 2.62 and 2.06, with 95% CI of 1.83, 3.76, and 1.03-4.11, respectively. Endometrial thickness was compared in 4 RCTs (307 participants) and 9 non-RCTs (675 participants), which showed a mean difference of 0.93 and 1.16, with 0.59-1.27 and 0.68-1.65 95% CI, respectively.

CONCLUSION

PRP administration improves implantation, clinical pregnancy, chemical pregnancy, ongoing pregnancy, live birth rates, and endometrial thickness in women with previous implantation failure.

Human Umbilical Cord-Based Therapeutics: Stem Cells and Blood Derivatives for Female Reproductive Medicine

There are several conditions that lead to female infertility, where traditional or conventional treatments have limited efficacy. In these challenging scenarios, stem cell (SC) therapies have been investigated as alternative treatment strategies. Human umbilical cord (hUC) mesenchymal stem cells (hUC-MSC), along with their secreted paracrine factors, extracts, and biomolecules, have emerged as promising therapeutic alternatives in regenerative medicine, due to their remarkable potential to promote anti-inflammatory and regenerative processes more efficiently than other autologous treatments. Similarly, hUC blood derivatives, such as platelet-rich plasma (PRP), or isolated plasma elements, such as growth factors, have also demonstrated potential. This literature review aims to summarize the recent therapeutic advances based on hUC-MSCs, hUC blood, and/or other plasma derivatives (e.g., extracellular vesicles, hUC-PRP, and growth factors) in the context of female reproductive medicine. We present an in-depth analysis of the principal molecules mediating tissue regeneration, compiling the application of these therapies in preclinical and clinical studies, within the context of the human reproductive tract. Despite the recent advances in bioengineering strategies that sustain delivery and amplify the scope of the therapeutic benefits, further clinical trials are required prior to the wide implementation of these alternative therapies in reproductive medicine.

[Synthetic bone replacement substances]

Bone substitute materials have been successfully used for bone defects in orthopedics and trauma surgery for a long time; however, there are cases, especially in bone defects with a critical size, in which the treatment is complicated. Nowadays, multiple bone substitute materials are available. Autologous cancellous bone grafts remain the gold standard among the bone replacement materials; however, donor site morbidity and the limited availability of autologous cancellous bone represent restrictions for autologous bone grafting. Allogeneic cancellous bone grafts have also been successfully for years in the treatment of bone defects; however, infection rates of more than 10% have been described for the use of allogeneic cancellous bone. By introducing synthetic bone substitutes further alternatives are currently available to the user for the individual treatment of bone defects. The aim of this study is to demonstrate the advantages and disadvantages of various synthetic bone substitute materials.

Efficacy of Autologous Intrauterine Infusion of Platelet-Rich Plasma in Patients with Unexplained Repeated Implantation Failures in Embryo Transfer: A Systematic Review and Meta-Analysis

(1) Background: Controversial conclusions have been made in previous studies regarding the influence of autologous platelet-rich plasma (PRP) in the reproductive outcomes of women with repeated implantation failures (RIF) who are undergoing embryo transfer (ET). (2) Methods: This study aimed to evaluate the effect of PRP intrauterine infusion in patients with unexplained RIF, who are undergoing in vitro fertilization (IVF) or intracytoplasmic injection (ICSI), by a systematic review and meta-analysis. (3) Results: A fixed-effects model was used, and 795 cases and 834 controls were included in these studies. The pooling of the results showed the beneficial effect of PRP which were compared with those of the control in terms of the clinical pregnancy rates (n = 10, risk ratio (RR) = 1.79, 95% confidence intervals (CI): 1.55, 2.06; p < 0.01, I2 = 40%), live birth rates (n = 4, RR = 2.92, 95% CI: 2.22, 3.85; p < 0.01, I2 = 83%), implantation rates (n = 3, RR = 1.74, 95% CI: 1.34, 2.26; p < 0.01, I2 = 0%), and positive serum β-HCG 14 days after the ET (n = 8, RR = 1.77, 95% CI: 1.54, 2.03; p < 0.01, I2 = 36%). However, we did not find that the miscarriage rates indicated a significant difference between the two groups (n = 6, RR = 1.04, 95% CI: 0.72, 1.51; p = 0.83, I2 = 0%). (4) Conclusions: The findings of this systemic review and meta-analysis suggest that PRP appears to improve the results of IVF/ICSI treatments in the cases of unexplained RIF.

Variability in Platelet-Rich Plasma Preparations Used in Regenerative Medicine: A Comparative Analysis

Background

Platelet-rich plasma (PRP) and its derivatives are used in several aesthetic, dental, and musculoskeletal procedures. Their efficacy is primarily due to the release of various growth factors (GF), interleukins, cytokines, and white blood cells. However, the PRP preparation methods are highly variable, and studies lack consistency in reporting complete procedures to prepare PRP and characterize PRP and its derivatives. Also, all the tissue-specific (in vivo and in vitro) interactions and functional properties of the various derivatives/factors of the PRP have not been taken into consideration by any study so far. This creates a potential space for further standardization of the PRP preparation methods and customization of PRP/PRP derivatives targeted at tissue-specific/pathology specific requirements that would enable efficacious and widely acceptable usage of PRP as main therapy, rather than being used as adjuvant therapy. The main objective of our study was to investigate the variability in PRP preparation methods and to analyze their efficacy and reliability.

Method

This study considered articles published in the last 5 years, highlighting the variability in their PRP preparation methods and characterization of PRP. Following the PRISMA protocol, we selected 13 articles for the study. The selected articles were assessed using NHLBI quality assessment tool.

Results

We noted differences in (1) approaches to producing PRP, (2) extent of characterization of PRP, (3) small scale and large-scale preparation methods, (4) in vitro and in vivo studies.

Conclusion

We identified two studies describing the procedures which are simple, reproducible, economical, provide a good yield of platelets, and therefore can be considered methods for further tissue-specific and pathology-specific standardizations of PRP and its derivatives. We recommend further randomized studies to understand the full therapeutic potential of the constituents of PRP and its derivatives.

Efficacy of Platelet-Rich Plasma in the Treatment of Fractures: A Meta-Analysis

Background

Although numerous studies have reported the effectiveness of platelet-rich plasma (PRP) in promoting and enhancing bone healing, many orthopedic physicians remain skeptical of platelet-rich plasma in the treatment of fractures. The objective of this meta-analysis was to assess the efficacy of PRP in the treatment of fractures.

Methods

We search for research on PRP treatment of fractures in Pubmed, Embase, Medline, and Cochrane libraries. Two independent reviewers assessed included studies and met to develop a consensus on included studies. We also assessed the risk of bias using Review Manager 5.3 software.

Results

The present meta-analysis included 10 randomized controlled trials (RCT) containing 652 patients. In the fixed-effect meta-analysis of 10 RCTs, 8 RCTs found that fracture patients benefited from PRP treatment. The use of PRP reduced the time of fracture healing in 4 RCTs. Three RCTs found that PRP adjuvant therapy enhanced bone mineral density in the fracture trace and reduced the time of bone regeneration in mandibular fractures patients (standardized mean difference (SMD) = −1.99, 95%confidence interval (CI) = −2.64–−1.35). And 3 RCTs found that PRP adjuvant therapy decreased the risk of revision surgery in fracture patients (SMD = 1.83, 95%CI = 1.10–3.04).

Conclusion

PRP adjuvant therapy is beneficial for the treatment of fracture patients, particularly those with mandibular fractures, and decreased the risk of revision surgery in fracture patients.

Ultrasound-guided injection of platelet-rich plasma or cord blood platelet-rich plasma in nonunion: a randomized controlled trial

Aim: To compare the ability of autologous platelet-rich plasma (PRP) and cord blood PRP (PRPc) to accelerate bone healing. Patients & methods: 71 patients with mechanically stable nonunion were treated weekly (3 consecutive weeks) with ultrasound-guided percutaneous injections of PRP or PRPc in a controlled randomized clinical trial. The primary outcome was healing (12 months) and secondary outcomes were radiological evolution (2 and 6 months) and changes in pain intensity (6 months). Results & conclusion: Bone consolidation was assessed over time without significant differences between PRP and PRPc treatment. In patients with persistent nonunion, pain perception decreased more after PRP treatment. PRPc appears to be a valid alternative when specific clinical conditions suggest avoiding the use of autologous blood products.

Is induced membrane technique effective in reconstruction of mandibular segmental bone defects? An experimental study

This study aimed to compare the effectiveness of different graft materials using induced membrane technique for reconstruction of mandibular segmental bone defects. New Zealand rabbits were used as the experimental animal. As first-stage surgical procedure, segmental bone defects were created at the lower border of the mandibula in all groups. Polymethylmethacrylate (PMMA) cement was inserted into the defects. After 6 weeks, PMMA cement was removed in all groups. In the Control group, defect areas were left empty. Defects were filled with autogenous graft in the Autograft group, xenograft in the Xenograft group, and a mixture of autogenous graft and xenograft in the Autograft + Xenograft group. Histopathological, stereological, and immunohistochemical analyses were performed. A total of 40 New Zealand rabbits were used. Rabbits were randomly divided into four subgroups as Control, Autograft, Xenograft and Autograft + Xenograft groups (n = 10). When the groups were compared in terms of newly formed bone tissue volumes, significant difference was found between the Control group and Autograft group, Xenograft group and Autograft + Xenograft group (p < 0.001, p < 0.001, p = 0.003). The results of immunohistochemical examination were consistent with this finding. Stereological and immunohistochemical results can be used as a justification to adopt the induced membrane technique on an experimental basis in humans when it comes to the reconstruction of small segmental mandibular defects.

Preparation and growth factor characterization of cord blood-derived plasma, serum, growth factor-rich plasma and induced serum

BACKGROUND

In recent years, there has been a significant decline in the demand for cord blood units (CBUs). This trend has led to cord blood banks (CBBs) exploring complementary uses of CBUs in order to exploit the full potential of this unique, valuable, and readily available product. The aim of this study was to establish standardized protocols for the preparation of four cord blood (CB) derivatives: plasma (CB-P), serum (CB-S), induced-serum (CB-IS) and growth factor-rich plasma (GFRP); to measure their respective growth-factor content and their potential as cell culture supplements, and finally, to identify the characteristics of each derivative beyond their growth-factor composition, in the context of optimizing CBBs resources.

STUDY DESIGN AND METHOD

To this end, CB plasma and serum were prepared and their concentrations for ten growth factors (TGF-β1, TGF-β2, TGF-β3, EGF, HGF, PDGF-BB, VEGF-A, VEGF-D, IGF-I, IGF-II) were determined using a multiplex bead array, and compared to adult plasma and serum. Protocols for the preparation of CB-IS and GFRP with reverse anticoagulation using CaCl₂·2H₂O were also established, and all four derivatives were compared for their EGF and TGF-β1 content by enzyme-linked immunosorbent assay (ELISA), and also for their cell culture supplement capacity.

RESULTS

CB plasma was shown to be richer than adult plasma for TGF-β2 and TGF-β3, with a lower concentration of IGF-I and IGF-II. CB serum was shown to be richer than adult serum for TGF-β2, TGF-β3, EGF, HGF, PDGF-BB, and VEGF-A and D, and poorer in IGF-I and II. The measure of EGF and TGF-β1 concentrations has shown that CB serum is the most concentrated (1874 pg/ml and 41 094 pg/ml) of the CB derivatives, followed by induced-serum (405 pg/ml and 16 735 pg/ml), growth factor-rich plasma (131 and 7947 pg/ml) and plasma (8 and 2845 pg/ml). All four CB derivatives were shown to be superior to FBS in sustaining cell growth at low doses.

CONCLUSION

Our study shows that four CB derivatives can be easily prepared and pooled to provide significant volume of products that vary in their growth factor composition. A cord blood bank interested in introducing such manufacturing will need to evaluate the financial and processing characteristics of each derivative. The use of standardized manufacturing protocols such as the ones we suggest could help research initiatives exploring the potential therapeutic uses of such rich and high-quality starting material.

Bioengineered endometrial hydrogels with growth factors promote tissue regeneration and restore fertility in murine models

Extracellular matrix (ECM) hydrogels obtained from decellularized tissues are promising biocompatible materials for tissue regeneration. These biomaterials may provide important options for endometrial pathologies such as Asherman's syndrome and endometrial atrophy, which lack effective therapies thus far. First, we performed a proteomic analysis of a decellularized endometrial porcine hydrogel (EndoECM) to describe the specific role of ECM proteins related to regenerative processes. Furthermore, we investigated the ability of a bioengineered system-EndoECM alone or supplemented with growth factors (GFs)-to repair the endometrium in a murine model of endometrial damage. For this model, the uterine horns of female C57BL/6 mice were first injected with 70% ethanol, then four days later, they were treated with: saline (negative control); biotin-labeled EndoECM; or biotin-labeled EndoECM plus platelet-derived GF, basic fibroblast GF, and insulin-like GF 1 (EndoECM+GF). Endometrial regeneration and fertility restoration were evaluated by assessing the number of glands, endometrial area, cell proliferation, neaoangiogenesis, reduction of collagen deposition, and fertility restoration. Interestingly, regenerative effects such as an increased number of endometrial glands, increased area, high cell proliferative index, development of new blood vessels, reduction of collagen deposition, and higher pregnancy rate occurred in mice treated with EndoECM+GF. Thus, a bioengineered system based on EndoECM hydrogel supplemented with GFs may be promising for the clinical treatment of endometrial conditions such as Asherman's syndrome and endometrial atrophy. STATEMENT OF SIGNIFICANCE: In the last years, the bioengineering field has developed new and promising approaches to regenerate tissues or replace damaged and diseased tissues. Bioengineered hydrogels offer an ideal option because these materials can be used not only as treatments but also as carriers of drugs and other therapeutics. The present work demonstrates for the first time how hydrogels derived from pig endometrium loaded with growth factors could treat uterine pathologies in a mouse model of endometrial damage. These findings provide scientific evidence about bioengineered hydrogels based on tissue-specific extracellular matrix offering new options to treat human infertility from endometrial causes such as Asherman's syndrome or endometrial atrophy.

Approaches to Improve Endometrial Receptivity in Case of Repeated Implantation Failures

Repeated implantation failures are a constant challenge in reproductive medicine with a significant impact both on health providers and on infertile couples. Several approaches have been proposed so far as effective; however, accumulative data have clarified that most of the treatment options do not have the evidence base for a generalized application to be suggested by the relevant societies. Implantation failures are attributed to either poor quality embryos or to defected endometrial receptivity. The current review aims to summarize in a systematic way all the new trends in managing RIF via interference with endometrial receptivity. The authors focus mainly, but not exclusively, on endometrial injury prior to embryo transfer and endometrial priming with autologous cells or biological agents. To this direction, a systematic search of the Pubmed database has been conducted taking into account the emerged evidence of the last two decades. All the suggested interventions are herein presented and analyzed in terms of reproductive outcomes. It is evident that properly powered and designed randomized trials are needed to support a new standard approach in RIF treatment that will safely be incorporated in national and international guidelines.

Cord Blood Platelet Rich Plasma Derivatives for Clinical Applications in Non-transfusion Medicine

Cord blood platelet rich plasma (CB-PRP) derivatives have been investigated as potential therapeutic agents for the treatment of diverse conditions including ocular surface disease and skin ulcers. We have developed processes for the formulation of several CB-PRP preparations, which have different composition and attributes. Here we describe the molecular characteristics of these preparations and we make recommendations as to their most appropriate clinical application based on functional and immunomodulatory profiles. We show that incubation of adult peripheral blood mononuclear cells (PBMCs) with all three preparations dramatically reduced the production of INFγ and the expression of NKG2D and CD107a in NK, NKT, and T cells thus diminishing their activation, we propose that the likely mechanism is the high levels of soluble NKG2D ligands present in plasma. Of the three preparations we investigated, CB platelet lysate (PL) and platelet releaseate (PR) have higher concentrations of trophic and pro-angiogenic factors, CB platelet poor plasma (PPP) has the lowest concentration of all analytes measured. Based on these finding we propose that CB-PR is the most suitable raw material for skin wound patches, while CB-PL and PPP can be used to prepare eye drops for severe ocular surface pathologies and inflammatory conditions such as corneal ulcers or severe dry eye disease, respectively.

Bone Substitutes in Orthopaedic Surgery: Current Status and Future Perspectives

Bone replacement materials have been successfully supplied for a long time. But there are cases, especially in critical sized bone defects, in which the therapy is not sufficient. Nowadays, there are multiple bone substitutes available. Autologous bone grafts remain the "gold standard" in bone regeneration. Yet, donor-site morbidity and the available amount of sufficient material are limitations for autologous bone grafting. This study aimed to provide information about the current status in research regarding bone substitutes. We report on the advantages and drawbacks of several bone substitutes. At the end, we discuss the current developments of combining ceramic substitutes with osteoinductive substances.