Autologization of Exosomes with Deparenchymized Adipose Tissue: An Innovative Approach for Regenerative Medicine and Surgery.

Background: Among all regenerative applications developed in recent years, the use of exosomes has generated by far the greatest interest. Exosome products from allogeneic and xenogeneic sources are available on the market. A key challenge is controlling the effects of nonautologous exosomes. We hypothesized that combining exosomes with a patient's own extracellular matrix (ECM) can create "autologization," enabling control over their effects. This study aimed to provide the rationale and a guide for future research exploring the autologization of exosome applications using deparenchymized adipose tissue (DPAT). Methods: DPAT adipose tissue was achieved using 1200-, 400-, and 35-micrometer blades in an ultrasharp blade system (Adinizer), and then "autologization" was achieved by combining the obtained DPAT with allogeneic exosomes. DPAT was evaluated histochemically, and exosomes were counted and analyzed with the Nanosight device. Results: The DPAT process using ultrasharp blades is easily performed. DPAT obtained from adipose tissue was then combined with allogenic exosomes. It has been demonstrated histopathologically that adipocytes are eliminated in deparenchymized fat tissue, and only ECM and stromal cells remain. It has also been proven that the number of exosomes is not affected by the combination. Conclusions: This study introduces two novel concepts previously unknown in the literature, "deparenchymization" and "autologization," representing an innovative approach in plastic surgery and regenerative medicine. Our novel approach enriches regenerative cells while preserving critical ECM signals, overcoming the limitations of existing isolation methods. Extensive research is still needed, but autologization using DPAT ECM holds great promise for translating exosome-based treatments into practice.

A New Classification for Adipose-derived Stromal-cell Systems.

Obtaining regenerative cells from adipose tissue and their clinical use has become one of the most popular subjects of plastic surgery. However, there is no accepted classification in terms of methods. In this study, classification is proposed for the first time as a new idea. Accordingly, stromal cells can be obtained from adipose tissue by two approaches: direct methods for the bonds between parenchymal and stromal cells, and indirect methods, which target parenchymal cells rather than strong bonds, and increase the stromal cell ratio relatively. These methods can also be subclassified as fat (+), fat (-), fat (±) in terms of using the remaining fat in the final product as a graft. Direct methods include adinizing and enzymatic techniques; indirect methods include emulsification and micro-fragmentation/micronization techniques. In the enzymatic method, the fat tissue in the final product is considered dirty because it contains enzymes and must be discarded. That is why it is a fat (-) method. The adinizing method using ultra-sharp blades is fat (+) because the adipose tissue after the procedure can be used. Because the fat tissue is exposed to blunt pressure in emulsification techniques, it cannot be used as a graft. Thus, these are fat (-) methods. In micronization techniques using filter systems, there may still be intact adipocytes; therefore, it should be classified as fat (±). Adinizing provides both the highest efficiency and the full use of the end product. This classification will guide clinicians in terms of choosing the right product.

Indication-based protocols with different solutions for mechanical stromal-cell transfer.

BACKGROUND: Regenerative medicine is the fastest developing branch of plastic surgery in recent times. Adipose tissue is one of the largest and most important sources in the body for stromal cells. Although mechanical isolation methods are both very popular and have many advantages, they still have no accepted protocols. OBJECTIVE: We developed new protocols called indication-based protocols (IPs) for standardization and new techniques called mechanical stromal-cell transfer (MEST) by using ultra-sharp blades and dilution of adipose tissue with different solutions (saline, Ringer and 5% Dextrose)Methods & material: In order to obtain the desired physical structure (liquid, gel, solid) and the desired volume, four different types of IPs have been defined. Adipose tissue was prediluted with different solutions using 10 or 20 cc injectors in IPs 1 and 2, while condensed adipose tissue was used directly in IPs 3 and 4. RESULTS: In MEST, stromal cells were obtained from 100 mL of condensed fat using different IPs with 92% mean viability and cell counts of 26.80-91.90 × 106. Stromal cells can be obtained in the desired form and number of cells by using four different IPs. CONCLUSION: Isolation of stromal cells by cutting fat with sharp blades will prevent the death of fat tissue and stromal cells and will allow high viability and cell count with our new technique. Predilution with different solutions: Diluting the condensed adipose tissue with the desired solutions (saline, Ringer or 5% Dextrose) before the adinizing process will provide even more stromal cells. LAY SUMMARY: Obtaining regenerative stromal cells from adipose tissue can be done by two methods: Enzymatic and mechanical. Mechanical methods have many advantages. Although mechanical stromal cell extraction from adipose tissue is very popular and many techniques have been described, there are still no accepted protocols, definition for the end product, and no consensus on the status of the stromal cells. In this study, stromal cells were obtained mechanically by using ultra-sharp blade systems, without exposing adipose tissue to blunt trauma. Thus, a higher number of cells and higher viability could be obtained. An "Indication based" protocol has been defined for the first time in order to obtain the desired number and status (solid, semi-solid, liquid)end product. Diluting the condensed adipose tissue with the desired solutions (saline, Ringer or 5% Dextrose) before the adinizing process will provide even more stromal cells. This will provide an opportunity for clinicians to obtain and apply a stromal cell solution for different indications in different anatomical regions.

Supercharged Mechanical Stromal-cell Transfer (MEST).

PRP and fat-derived stromal-cell applications are the 2 most commonly used methods in regenerative medicine. PRP has a wide spectrum of indications. Mechanical methods have become very popular recently in fat-derived stromal-cell applications due to the advantages they provide. Combining these 2 methods has produced more successful results. To date, this combination has been in the form of combining 2 products obtained separately just before they are administered to the patient. In this study, fat tissue and blood samples obtained from eight volunteers were mixed with PPP as a new idea not previously reported in the literature, and stromal cells were obtained mechanically with sharp blades (adinizing). Later, the obtained PRP was added to the final product and became "supercharged." The results were tested by the dual fluoroscopy method for cell number and viability, and the results obtained were analyzed statistically. By adding the plasma to the oil before stromal cells were obtained and cutting with sharp blades by mechanical separation, twice the volume and 4.7 times more cells were obtained compared with that obtained in the saline group (P < 0.001). We believe that the reason for this is the "binding" effect of the proteins in the plasma. This approach provided a higher cell count by using PPP, which is a "waste product," and in addition, the potential efficiency was increased by adding PRP. However, the clinical results of this innovative method should be evaluated with advanced clinical studies.

Not Stromal Vascular Fraction (SVF) or Nanofat, but Total Stromal-Cells (TOST): A New Definition. Systemic Review of Mechanical Stromal-Cell Extraction Techniques.

The most important and greatest source in the body for regenerative cells is fat tissue. Obtaining regenerative cells from adipose tissue can be done in two ways: Enzymatic and mechanical. The regenerative cell cocktail obtained by the enzymatic method, including stem cells, is called Stromal vascular fracture (SVF). In the literature, there is no clear definition of regenerative cells obtained by mechanical method. We systematically searched the techniques and definitions for stromal cells obtained from adipose tissue by scanning different databases. To evaluate the mechanical stromal-cell isolation techniques and end products from adipose tissue. Systematic review of English and non-English articles using Embase, PubMed, Web of Science and Google scholar databases. Search terms included Nanofat, fragmented fat, mechanical stromal / stem cell, mechanical SVF, SVF gel. We screened all peer-reviewed articles related with mechanical stromal-cell isolation. Author performed a literature query with the aforementioned key words and databases. A total of 276 publications containing the keywords we searched were reached. In these publications, there are 46 different definitions used to obtain mechanical stromal cells. The term SVF is only suitable for enzymatic methods. A different definition is required for mechanical. The most used term nanofat is also not suitable because the product is not in both "fat" and in "nanoscale". We think that the term total stromal-cells would be the most appropriate definition since both extracellular matrix and all stromal cells are protected in mechanical methods.

New normal: two aspects of adipose tissue in COVID-19-treat and threat?

INTRODUCTION: Adipose-derived stromal cells (ADSCs) can be an important alternative in COVID-19 prevention, treatment, and subsequent sequelae repair. However, ACE-2 plays a common role in the pathogenesis of adipocyte hypertrophy and COVID 19. AREAS COVERED: In this 'Perspective,' the author would like to emphasize the use of adipose tissue-derived stromal cells in COVID 19 and the issues that clinicians should pay attention to in fat graft applications in terms of adipose tissue-RAS relationship. The new normal for adipose tissue in COVID 19 will be highlighted. EXPERT OPINION: ADSCs may potentially be used in COVID-19. However, it has been speculated that ACE2 receptors are responsible for the pathogenesis of adipose tissue overgrowth and may be a potential danger in terms of the relationship between ACE2 receptors and COVID19. We speculate that reducing the size of overgrown fat tissue by ultra-sharp blades and using near-normal adipocytes will create a 'new normal.'

New Mechanical Fat Separation Technique: Adjustable Regenerative Adipose-tissue Transfer (ARAT) and Mechanical Stromal Cell Transfer (MEST).

BACKGROUND: Adipose tissue is not only a very important source of filler but also the body's greatest source of regenerative cells. OBJECTIVES: In this study, adipose tissue was cut to the desired dimensions using ultra-sharp blade systems to avoid excessive blunt pressure and applied to various anatomical areas-a procedure known as adjustable regenerative adipose-tissue transfer (ARAT). Mechanical stromal cell transfer (MEST) of regenerative cells from fat tissue was also examined. METHODS: ARAT, MEST, or a combination of these was applied in the facial area of a total of 24 patients who were followed for at least 24 months. The integrity of the fat tissue cut with different diameter blades is shown histopathologically. The number and viability of the stromal cells obtained were evaluated and secretome analyses were performed. Patient and surgeon satisfaction were assessed with a visual analog scale. RESULTS: With the ARAT technique, the desired size fat grafts were obtained between 4000- and 200-micron diameters and applied at varying depths to different aesthetic units of the face, and a guide was developed. In MEST, stromal cells were obtained from 100 mL of condensed fat using different indication-based protocols with 93% mean viability and cell counts of 28.66 to 88.88 × 106. CONCLUSIONS: There are 2 main complications in fat grafting: visibility in thin skin and a low retention rate. The ARAT technique can be used to prevent these 2 complications. MEST, on the other hand, obtains a high rate of fat and viable stromal cells without applying excessive blunt pressure.