Comparison between platelet-rich plasma (PRP) and mechanically emulsified fat grafts in management of chronic wounds

Nanofat Use in Regenerative Medicine: A Systematic Literature Review and Consensus Recommendations from Expert Opinions

Objective: To report in vitro, preclinical, and clinical effectiveness of nanofat in adults undergoing reconstructive or functional surgery and to produce a series of consensus statements about nanofat definition by experts. Methods: We conducted a systematic review using PubMed and Web of Science database, retaining studies about nanofat alone. To produce consensus recommendations about nanofat, we invited experts to answer a survey about manufacturing, biological characteristics, and nomenclature of nanofat. Results: A review of 39 articles showed that nanofat seems to have strong regenerative potential. There were 16 studies about the clinical effectiveness of the nanofat in wound healing, aesthetic surgery, and functional disabilities. However, majority of applications lack robust clinical evidence, mainly due to the design of the clinical studies. The experts suggested that nanofat refers to lipoaspirate that benefits from a washing step, followed by emulsification (20-30 passes) with a connector size between 1.2 and 1.6 mm, and a final filtration step (pore size around 300-500 µm). Conclusion: Nanofat seems to have strong regenerative potentials but with a lack of robust clinical evidences. Our experts have suggested the first consensus about a definition of the nanofat that can be used by the academic societies in the coming years.

Leukocyte Platelet-Rich Plasma-Derived Exosomes Restrained Macrophages Viability and Induced Apoptosis, NO Generation, and M1 Polarization

BACKGROUND

Chronic refractory wounds refer to wounds that cannot be repaired timely. Platelet-rich plasma (PRP) has significant potential in chronic wound healing therapy. The exosomes isolated from PRP were proved to exhibit more effectiveness than PRP. However, the therapeutic potential of exosomes from PRP on chronic refractory wounds remained elusive. Hence, this study aimed to clarify the action of exosomes from PRP on chronic refractory wounds by evaluating the response of macrophages to exosomes.

METHODS

Pure platelet-rich plasma (P-PRP) and leukocyte platelet-rich plasma (L-PRP) were prepared from the fasting venous blood of healthy volunteers. Exosomes were extracted from P-PRP and L-PRP using ultracentrifugation and identified by transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA), and western blot. Macrophages were obtained by inducing THP-1 cells with phorbol-12-myristate-13 acetate (PMA). The internalization of exosomes into macrophages was observed utilizing confocal laser scanning microscopy after being labeled with PKH67. Cell viability was determined by CCK-8 assay. Cell apoptosis was measured utilizing a flow cytometer. The polarization status of M1 and M2 macrophages were evaluated by detecting their markers. Nitric oxide (NO) detection was conducted using the commercial kit.

RESULTS

Exosomes from P-PRP and L-PRP were absorbed by macrophages. Exosomes from L-PRP restrained viability and induced apoptosis of macrophages. Besides, exosomes from P-PRP promoted M2 polarization, and exosomes from L-PRP promoted M1 polarization. Furthermore, exosomes from L-PRP promoted NO generation of macrophages.

CONCLUSION

Exosomes from L-PRP restrained viability, induced apoptosis and NO generation of macrophages, and promoted M1 polarization, while exosomes from P-PRP increased M2 polarization. The exosomes from L-PRP presented a more effective effect on macrophages than that from P-PRP, making it a promising strategy for chronic refractory wound management.

MOF@platelet-rich plasma antimicrobial GelMA dressing: structural characterization, bio-compatibility, and effect on wound healing efficacy

In this study, a metal-organic framework (MOF) antimicrobial gel loaded with platelet-rich plasma (PRP) was prepared to improve the biological properties of gelatin gels and enhance their wound healing efficiency. PRP, MOF particles, and PRP-loaded MOF particles were each integrated into gelatin gels. The performance of the gels was evaluated for micro-structure, mechanical strength, in vitro bio-compatibility and pro-wound healing effects. The results revealed that the integration of PRP created a multi-cross-linked structure, increasing the ductility of the gels by over 40%. The addition of MOF particles significantly increased the strength of the gel from 13 kPa to 43 kPa. The combination of MOF and PRP further improved the cell induction and migration capabilities of the composite gel, and the scratches in the PRP/MOF@GelMA group had completely healed within 48 h. Due to the presence of MOF and PRP, the gel dressing exhibited inhibitory effects of 45.7% against Staphylococcus aureus (S. aureus) and 50.2% against Escherichia coli (E. coli). Different gels promoted tissue regeneration and wound healing ability of bacterial-infected wounds in C57 rats, while PRP/MOF@GelMA showed the strongest wound repair ability with 100% healing. This study provides a new strategy for the development and clinical application of gel dressings.

The Application of Blood Products in Plastic Surgery: A Systematic Review

Background

Due to their minimal trauma and relative safety, blood products are becoming increasingly popular in medical aesthetics. In recent years, research on the application of blood products has also been increased. This article will summarize the research progress of emerging blood products in plastic surgery in recent years.

Methods

We searched the PubMed database for literature related to the application of blood preparation in plastic surgery over the past 5 years and summarized them.

Results

Commonly used in plastic surgery are platelet-rich plasma, platelet-rich fibrin, concentrated growth factor, platelet-poor plasma, and mesenchymal stem cells derived from blood products. They can be used for wound repair and skin and autologous fat transplantation, and can be combined with laser therapy and facial rejuvenation.

Conclusions

Understanding the application pathways of blood products in plastic surgery and their respective advantages and disadvantages can help us better choose and use them.