Treatment of human chronic wounds with autologous extracellular matrix/stromal vascular fraction gel: A STROBE-compliant study

The role of orthobiologics in chronic wound healing

Chronic wounds, characterized by prolonged healing processes, pose a significant medical challenge with multifaceted aetiologies, including local and systemic factors. Here, it explores the complex pathogenesis of chronic wounds, emphasizing the disruption in the normal phases of wound healing, particularly the inflammatory phase, leading to an imbalance in extracellular matrix (ECM) dynamics and persistent inflammation. Senescent cell populations further contribute to impaired wound healing in chronic lesions. Traditional medical management focuses on addressing underlying causes, but many chronic wounds resist to conventional treatments, necessitating innovative approaches. Recent attention has turned to autologous orthobiologics, such as platelet-rich plasma (PRP), platelet-rich fibrin (PRF) and mesenchymal stem cells (MSCs), as potential regenerative interventions. These biologically derived materials, including bone marrow aspirate/concentrate (BMA/BMAC) and adipose tissue-derived stem cells (ADSCs), exhibit promising cytokine content and regenerative potential. MSCs, in particular, have emerged as key players in wound healing, influencing inflammation and promoting tissue regeneration. This paper reviews relevant scientific literature regarding basic science and brings real-world evidence regarding the use of orthobiologics in the treatment of chronic wounds, irrespective of aetiology. The discussion highlights the regenerative properties of PRP, PRF, BMA, BMAC and SVF, showcasing their potential to enhance wound healing. Despite advancements, further research is essential to elucidate the specific roles of each orthobiologic and determine optimal applications for different wound types. The conclusion underscores the evolving landscape in chronic wound management, with a call for more comprehensive studies to refine treatment strategies and maximize the benefits of regenerative medicine.

Treatment of pressure ulcers in patients with spinal cord injury: Conventional surgery vs. cellular therapy

CONTEXT

Relapse and recurrence rates of pressure injuries (PIs) are very high in spinal cord injured patients. That is the reason why alternative therapies, such the stem cells derived from bone marrow, have been developed.

OBJECTIVE

To compare this new technique of infiltration-infusion of mononuclear cells from bone marrow with conventional surgery.

DESIGN

A retrospective study was carried out in patients with spinal cord injuries who had PIs, category III/IV, in the pelvic area, during a 14-year follow-up period.

SETTING

One group was treated with conventional surgery and, in the other group, mononuclear cells were infused.

PARTICIPANTS

One hundred and forty-nine patients were registered, 63 (42.3%) in the conventional surgery group and 86 (57.7%) in the mononuclear cell group.

RESULTS

A comparative study between these 2 groups was carried out. There were no significant differences in ulcer healing in the first 6 months, but 6 months and one-year post-treatment, they were found. At 6 months, no patient in the conventional surgery group showed dehiscence or fistulization of the wound and, one year after surgery, only 3.17% recurred in the conventional group. In addition, there was a statistically significant relationship between days of hospitalization and the type of bacterial contamination and the intervention group.

CONCLUSION

Bone marrow mononuclear cell infusion-infiltration is an alternative treatment for PIs and fistula during the first 6 months, instead of conventional surgery. However, in the medium-long term, conventional surgery is more effective.

Exploring Preclinical Experiments with Different Fat Types for Autologous Fat Grafting

BACKGROUND

Autologous fat transplantation has been a cornerstone of tissue regeneration for decades. However, there is no standardized selection system or criteria for fat graft selection, often relying heavily on the surgeon's experience.

OBJECTIVES

This study aimed to investigate various types of fat derivatives, both in vitro and in vivo at the same condition.

METHODS

We collected traditional fat granules of different sizes and SVF-gel, evaluating the viability of ADSCs isolated from them and their performance after grafting into mice.

RESULTS

Large fat granules exhibited more complete adipocyte structures, and the isolated ADSCs demonstrated superior differentiation, proliferation, and secretion capacities. They also showed excellent volume retention after 12 weeks. In contrast, ADSCs isolated from SVF-gel displayed lower vitality. However, grafts from SVF-gel exhibited the highest volume maintenance rate among the four groups after 12 weeks, closely resembling normal adipose tissue and displaying significant vascularization. Compared to large fat granule and SVF-gel group, medium and small fat granule grafts exhibited lower volume retention and less angiogenesis.

CONCLUSIONS

Through preclinical studies, the flexible clinical use of different fat grafts can be tailored to their unique characteristics.

LEVEL OF EVIDENCE I

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Modern techniques in addressing facial acne scars: A thorough analysis

BACKGROUND

Facial acne scars are a prevalent concern, leading to the development of various treatment modalities.

OBJECTIVES

This review aims to explore the latest advancements in the treatment of facial acne scars, focusing on both surgical and non-surgical methods.

METHODS

The non-surgical treatments reviewed include topical medications (such as retinoids and alpha hydroxy acids) and non-invasive procedures (like microdermabrasion and chemical peels). Surgical options discussed are punch excision, subcision, and fractional laser treatments.

RESULTS

Combination therapy, integrating both surgical and non-surgical approaches, is frequently utilized to achieve optimal results in scar improvement.

CONCLUSION

Recent advancements in the treatment of facial acne scars provide promising options for individuals seeking improvement. However, these treatments have associated risks and potential adverse effects, highlighting the importance of consulting a dermatologist before beginning any treatment regimen.

Mechanical Fractionation of Adipose Tissue-A Scoping Review of Procedures to Obtain Stromal Vascular Fraction

Clinical indications for adipose tissue therapy are expanding towards a regenerative-based approach. Adipose-derived stromal vascular fraction consists of extracellular matrix and all nonadipocyte cells such as connective tissue cells including fibroblasts, adipose-derived stromal cells (ASCs) and vascular cells. Tissue stromal vascular fraction (tSVF) is obtained by mechanical fractionation, forcing adipose tissue through a device with one or more small hole(s) or cutting blades between syringes. The aim of this scoping review was to assess the efficacy of mechanical fractionation procedures to obtain tSVF. In addition, we provide an overview of the clinical, that is, therapeutic, efficacy of tSVF isolated by mechanical fraction on skin rejuvenation, wound healing and osteoarthritis. Procedures to obtain tissue stromal vascular fraction using mechanical fractionation and their associated validation data were included for comparison. For clinical outcome comparison, both animal and human studies that reported results after tSVF injection were included. We categorized mechanical fractionation procedures into filtration (n = 4), centrifugation (n = 8), both filtration and centrifugation (n = 3) and other methods (n = 3). In total, 1465 patients and 410 animals were described in the included clinical studies. tSVF seems to have a more positive clinical outcome in diseases with a high proinflammatory character such as osteoarthritis or (disturbed) wound healing, in comparison with skin rejuvenation of aging skin. Isolation of tSVF is obtained by disruption of adipocytes and therefore volume is reduced. Procedures consisting of centrifugation prior to mechanical fractionation seem to be most effective in volume reduction and thus isolation of tSVF. tSVF injection seems to be especially beneficial in clinical applications such as osteoarthritis or wound healing. Clinical application of tSVF appeared to be independent of the preparation procedure, which indicates that current methods are highly versatile.

Long-term follow-up and exploration of the mechanism of stromal vascular fraction gel in chronic wounds

BACKGROUND

Chronic refractory wounds easily relapse and seriously affect the patients' quality of life. Previous studies have shown that stromal vascular fraction gel (SVF-gel) significantly promotes the early healing of chronic wounds; however, the mechanisms of SVF-gel function per se remain unclear, and a long-term follow-up is lacking. This study aims to explore the mechanisms of SVF-gel promoting the healing of chronic wounds and follow up the long-term efficacy of SVF-gel.

METHODS

Autologous SVF-gel transplantation was performed in 20 patients with chronic wounds (from March 2016 to September 2019), and the size of the wound before and after SVF-gel transplantation was observed. The conditioned medium (CM) was harvested from SVF-gel under serum-free, serum-deprivation and 10% fetal bovine serum (FBS) microenvironment in vitro, respectively. The concentration of the growth factors in the two kinds of gel-CM was tested, and their effects on the proliferation and migration of human dermal fibroblasts (HDFs) were detected.

RESULTS

All patients had 100% wound closure eventually, and the average time to complete closure was 28.3 ± 9.7 days. The time of follow-up ranged from 2 to 6 years, and there was no wound recurrence. Interestingly, the concentrations of epidermal growth factor and transforming growth factor β1 of the CM were higher in serum-free and serum-deprivation condition than in 10% FBS microenvironment (p < 0.05). Correspondingly, the proliferation and migration ability of HDFs treated with gel-CM from serum-free condition were stronger than those treated with gel-CM from serum-deprivation (2% FBS) or 10% FBS microenvironment (p < 0.05).

CONCLUSION

These results indicate that it is safe, effective, and lasting in effect to treat chronic wounds with SVF-gel and mechanisms of action that include secreting various cytokines and promoting cell proliferation and migration ability.

TRIAL REGISTRATION

Chinese Clinical Trail Registry, ChiCTR2000034624. Registered 12 July 2020-Retrospectively registered, http://www.chictr.org.cn/showproj.aspx?proj=56058.

Safety and feasibility of autologous adipose-derived stromal vascular fraction in the treatment of keloids: a phase one randomized controlled pilot trial

INTRODUCTION

Autologous adipose-derived stromal vascular fraction (SVF) has been described to have therapeutic benefits in the treatment of keloids. However, most of the evidence on its efficacy is based on observational studies the majority of which are conducted in high-income countries and yet the highest burden of keloids is in low- and middle-income countries (LMICs).

OBJECTIVES

We set out to determine the safety and feasibility of using autologous adipose derived stromal vascular fraction in the treatment of keloids in LMICs.

METHODS

In this phase II randomized controlled pilot clinical trial conducted in the Plastic Surgery Unit of Kirruddu National Referral Hospital in Kampala Uganda, 8 patients were assigned a 1:1 ratio to either SVF or triamcinolone acetonide (TAC) arms. In the SVF arm, a median (Inter quartile range) amount of stromal cell infiltration of 2.7×10⁶ (11×10⁶) was administered, while the controls received 10 mg/ml TAC at a ratio of 1:1 TAC to keloid volume. Primary endpoints were adverse event development based on the Common Terminology Criteria for Adverse Events (CTCAE) v5.0 tool and feasibility assessment based on ≥ 70% recruitment feasibility and ≥ 80% interventional feasibility rates.

RESULTS

The participants' mean age was 27.9 (±6.5) years, with a female predilection of 5 (63%). Overall, no adverse events were reported in the SVF arm, while ulceration in a single patient in the TAC arm, which was a grade II adverse event, was reported. Recruitment feasibility of 80% and interventional feasibility with 100% completion were reported.

CONCLUSION

Based on our findings, an autologous adipose-derived stromal vascular fraction is feasible and safe for the treatment of keloids in LMICs.

Mechanical Micronization of Lipoaspirates Combined with Fractional CO 2 Laser for the Treatment of Hypertrophic Scars

BACKGROUND

Treating hypertrophic scars remains challenging. Stromal vascular fraction (SVF) gel is produced by a purely mechanical process from lipoaspirates, rich in adipose-derived stem cells, and has showed therapeutic potential on scars. However, controversial effects on hypertrophic scars are emerging. This study aimed to assess the therapeutic effects of SVF gel combined with fractional CO 2 laser on hypertrophic scars.

METHODS

A rabbit ear hypertrophic scar model was established. SVF gel combined with fractional CO 2 laser was conducted for hypertrophic scars in rabbits. Scar alleviation in rabbits was observed based on the appearance and histology of scars, and the underlying mechanism was investigated by tissue immunologic analyses and quantitative real time polymerase chain reaction. At last, six patients with hypertrophic scar were treated by SVF gel combined with fractional CO 2 laser. Therapeutic effects were assessed using the Vancouver Scar Scale.

RESULTS

Following the treatments, hypertrophic scars became less apparent and softer, the dermis became thinner, and collagen fibers appeared looser and arranged in a more organized pattern. The SVF gel plus fractional CO 2 laser group showed the most obvious improvement. In addition, SVF gel combined with fractional CO 2 laser increased adipogenesis in scar tissue, and adipose tissue regeneration was observed. Hypertrophic scars in patients were alleviated after treatment with SVF gel combined with fractional CO 2 laser.

CONCLUSIONS

SVF gel transplantation combined with fractional CO 2 laser showed encouraging therapeutic effects on hypertrophic scars. Although further investigation is necessary, this technique has great potential for clinical application to treat hypertrophic scars.

CLINICAL RELEVANCE STATEMENT

This is a new technique for treating hypertrophic scars.

Review: Research progress of adipose-derived stem cells in the treatment of chronic wounds

Although methods are used to treat wounds clinically, there are still many challenges in the treatment of chronic wounds due to excessive inflammatory response, difficulties in epithelialization, vascularization, and other factors. With the increasing research on adipose-derived stem cells (ADSCs) in recent years, accumulating evidence has shown that ADSCs scan promotes the healing of chronic wounds by regulating macrophage function and cellular immunity and promoting angiogenesis and epithelialization. The present study reviewed the difficulties in the treatment of chronic wounds, as well as the advantages and the mechanism of ADSCs in promoting the healing of chronic wounds, to provide a reference for the stem cell therapy of chronic wounds.

Promoting repair of highly purified stromal vascular fraction gel combined with advanced platelet-rich fibrin extract for irradiated skin and soft tissue injury

Background

To evaluate the effect of highly purified stromal vascular fraction gel (SVFG) combined with advanced platelet-rich fibrin extract (APRFE) in treatment of irradiated skin and soft tissue injury.

Methods

The subcutaneous fat and whole blood of 4 rabbits were collected to isolate the SVFG and APRFE, respectively. Forty-eight rabbits were divided into 4 groups to prepare irradiated skin injury models with 25 Gy for 24 hours; corresponding dose were performed subcutaneously injected into wounds. In group A, the rabbits were treated with 0.3 mL APRFE combined with 1 mL SVFG. In group B, the rabbits were treated with 1 mL SVFG. In group C, the rabbits were treated with 0.3 mL APRFE, and group D was treated with 1 mL normal saline. The wound healing was detected on the 2, 5, 9 and 14 d after intervention. The wounds tissue was cut for hematoxylin and eosin (HE) staining to observe the structure and Masson staining to observe the collagen content. The expression of CD31 in each group was detected by immunohistochemistry (IHC), the protein and mRNA levels of K19, hypoxia inducible factor-1 alpha (HIF-1α), vascular endothelial growth factor (VEGF), interleukin 8 (IL-8) and interleukin 10 (IL-10) were detected respectively by Western blot (WB) and reverse transcription-polymerase chain reaction (RT-PCR) on 7, 14 and 28 d after intervention.

Results

It is revealed that wound healing rates from 5 to 14 d in group A was significantly higher than that of control. The wounds healing rates in group B and C were significantly higher than that of control after 12 d. Masson staining results showed that the collagen content in group A was significantly higher than that of the other 3 groups on the 7, 14 and 28 d. The results of IHC showed that the expression of CD31 in group A was significantly higher than that of the other 3 groups on 7, 14 and 28 d. WB and RT-PCR results showed that relative expression levels of K19, HIF-1α, VEGF, IL-10 in group A were significantly higher than that of the other 3 groups on 7, 14 and 28 d. However, the relative expression levels of IL-8 in group A was significantly lower than that of the other 3 groups on 7, 14 and 28 d.

Conclusions

SVFG combined with APRFE can promote the repair of irradiated skin and soft tissue injury by accelerating angiogenesis, promoting collagen synthesis and reducing inflammation.

Injection of freshly collected autologous adipose tissue in complicated pilonidal disease: a prospective pilot study

BACKGROUND

Pilonidal sinus disease (PSD) is a frequent disorder. Treatment failure and recurrence are common, leading to significant morbidity. The aim of this study was to investigate the impact and need for repeated treatment of injected autologous adipose tissue into non-healing PSD wounds and primary anal-near PSD or anal-near recurrence.

METHODS

At the Department of Surgery, Randers Regional Hospital, Denmark, a prospective pilot study was conducted on consecutive PSD patients with lack of healing 3 months after surgery (Bascom's cleft lift) or with primary or recurrent anal-near pilonidal sinus disease from December 2018 to March 2020. The primary endpoint was time to healing. Autologous adipose tissue was harvested from the patients and injected into the lesions after surgical revision. Patients were examined 2 and 12 weeks after surgery. Patients with lack of healing after 12 weeks (undermining or no skin coverage) were offered re-injection.

RESULTS

We included 30 patients [26 men and 4 women, median age 24 years (range 18-59 years)]. Complete healing was achieved in 25 patients [83.3%; 95% CI (69.9-96.7)]. Two patients had recurrence (6.7%). The median time to complete healing was 159 (189) days. The mean operation time was 70.6 ± 23.7 min and the mean amount of injected autologous adipose tissue was 19 ± 10 ml. There were no major complications.

CONCLUSION

Freshly collected autologous adipose tissue injected into chronic non-healing or primary and recurrent PSD lesions near the anal verge is safe and efficient.

Burn Wound Healing: Clinical Complications, Medical Care, Treatment, and Dressing Types: The Current State of Knowledge for Clinical Practice

According to the World Health Organization (WHO), it is estimated that each year approximately 11 million people suffer from burn wounds, 180,000 of whom die because of such injuries. Regardless of the factors causing burns, these are complicated wounds that are difficult to heal and are associated with high mortality rates. Medical care of a burn patient requires a lot of commitment, experience, and multidirectional management, including surgical activities and widely understood pharmacological approaches. This paper aims to comprehensively review the current literature concerning burn wounds, including classification of burns, complications, medical care, and pharmacological treatment. We also overviewed the dressings (with an emphasis on the newest innovations in this field) that are currently used in medical practice to heal wounds.

Autologous Stem Cell Therapy for Chronic Lower Extremity Wounds: A Meta-Analysis of Randomized Controlled Trials

Lower extremity chronic wounds (LECWs) commonly occur in patients with diabetes mellitus (DM) and peripheral arterial disease (PAD). Autologous stem cell therapy (ASCT) has emerged as a promising alternative treatment for those who suffered from LECWs. The purpose of this study was to assess the effects of ASCT on LECWs. Two authors searched three core databases, and independently identified evidence according to predefined criteria. They also individually assessed the quality of the included randomized controlled trials (RCTs), and extracted data on complete healing rate, amputation rate, and outcomes regarding peripheral circulation. The extracted data were pooled using a random-effects model due to clinical heterogeneity among the included RCTs. A subgroup analysis was further performed according to etiology, source of stem cells, follow-up time, and cell markers. A total of 28 RCTs (n = 1096) were eligible for this study. The pooled results showed that patients receiving ASCT had significantly higher complete healing rates (risk ratio (RR) = 1.67, 95% confidence interval (CI) 1.28–2.19) as compared with those without ASCT. In the CD34+ subgroup, ASCT significantly led to a higher complete healing rate (RR = 2.70, 95% CI 1.50–4.86), but there was no significant difference in the CD34− subgroup. ASCT through intramuscular injection can significantly improve wound healing in patients with LECWs caused by either DM or critical limb ischemia. Lastly, CD34+ is an important cell marker for potential wound healing. However, more extensive scale and well-designed studies are necessary to explore the details of ASCT and chronic wound healing.

Extracellular matrix-derived hydrogels to augment dermal wound healing: a systematic review

BACKGROUND

Chronic, non-healing, dermal wounds form a worldwide medical problem with limited and inadequate treatment options and high societal burden and costs. With the advent of regenerative therapies exploiting extracellular matrix (ECM) components, its efficacy to augment wound healing is to be explored. This systematic review was performed to assess and compare the current therapeutic efficacy of ECM hydrogels on dermal wound healing.

METHODS

The electronic databases of (Embase, Medline Ovid, Cochrane Central) were searched for in vivo and clinical studies on the therapeutic effect of ECM-composed hydrogels on dermal wound healing (13th of April 2021). Two reviewers selected studies independently. Studies were assessed based on ECM content, ECM hydrogel composition, additives and wound healing outcomes such as wound size, angiogenesis and complications.

RESULTS

Of the 2102 publications, nine rodent-based studies were included while clinical studies were not published at the time of the search. Procedures to decellularize tissue or cultured cells and subsequently generate hydrogels were highly variable and in demand of standardization. ECM hydrogels with or without additives reduced wound size and also seem to enhance angiogenesis. Serious complications were not reported.

CONCLUSION

To date, preclinical studies preclude to draw firm conclusions on the efficacy and working mechanism of ECM-derived hydrogels on dermal wound healing. The use of ECM hydrogels can be considered safe. Standardization of decellularization protocols and implementation of quality and cytotoxicity controls will enable obtaining a generic and comparable ECM product.

Comparison of Microfat, Nanofat, and Extracellular Matrix/Stromal Vascular Fraction Gel for Skin Rejuvenation: Basic Research and Clinical Applications

BACKGROUND

Over the past 2 decades, fat grafting has been extensively applied in the field of tissue regeneration.

OBJECTIVES

The aim of this study was to investigate the therapeutic potential of microfat, nanofat, and extracellular matrix/stromal vascular fraction gel (SVF-gel) in skin rejuvenation.

METHODS

Microfat was harvested by a cannula with multiple 0.8-mm smooth side holes and processed with a fat stirrer to remove fibers. Nanofat and SVF-gel were prepared according to previously reported methods, and their structure and viability were evaluated. Then, SVF cells from the 3 types of samples were isolated and characterized, and the cell viability was compared.

RESULTS

The microstructure of the 3 samples showed distinct differences. The microfat group showed a diameter of 100 to 120.0 μm under the microscope and presented a botryoid shape under calcein acetoxymethyl (calcein-AM)/propidium iodide staining. Scanning electron microscopy analysis showed that the microfat maintained an integral histologic structure. In the nanofat group, no viable adipocytes and no normal histologic structure were observed, but high levels of free lipids were noted. The SVF-gel group showed uniform dispersion of cells with different sizes and parts of the adipose histologic structure. Cell count and culture revealed that the number of viable SVF cells decreased distinctly in the nanofat group compared with the microfat group. In contrast, the number of viable SVF cells in the SVF-gel group increased moderately. Clinical applications with microfat showed marked improvements in skin wrinkles.

CONCLUSIONS

Microfat can preserve the integrity of the histologic structure and presents the advantages of subcutaneous volumetric restoration and improvement of skin quality in skin rejuvenation compared with the nanofat and SVF-gel.

LEVEL OF EVIDENCE: 5

Diabetic Wound-Healing Science

Diabetes mellitus is an increasingly prevalent chronic metabolic disease characterized by prolonged hyperglycemia that leads to long-term health consequences. It is estimated that impaired healing of diabetic wounds affects approximately 25% of all patients with diabetes mellitus, often resulting in lower limb amputation, with subsequent high economic and psychosocial costs. The hyperglycemic environment promotes the formation of biofilms and makes diabetic wounds difficult to treat. In this review, we present updates regarding recent advances in our understanding of the pathophysiology of diabetic wounds focusing on impaired angiogenesis, neuropathy, sub-optimal chronic inflammatory response, barrier disruption, and subsequent polymicrobial infection, followed by current and future treatment strategies designed to tackle the various pathologies associated with diabetic wounds. Given the alarming increase in the prevalence of diabetes, and subsequently diabetic wounds, it is imperative that future treatment strategies target multiple causes of impaired healing in diabetic wounds.

An Efficacy Study of a New Radical Treatment for Acne Vulgaris Using Fat Injection

BACKGROUND

Fat grafting is a popular operative approach for rejuvenation. Some patients requiring facial fat grafting also have acne. Fat grafting may improve acne in some patients.

OBJECTIVES

The aim of this study was to assess whether fat grafting can improve acne and to analyze the mechanism of action by which such improvement occurs.

METHODS

Preoperative and postoperative digital photographs were examined retrospectively in 229 patients who underwent fat grafting to compare the numbers of inflammatory acne lesions. In addition, 18 patients with acne who were treated by injection of subdermal stromal vascular fraction gel (SVF-gel) were examined prospectively. The numbers of inflammatory acne lesions before and after treatment were measured, and changes in the levels of CD4+ T-cell infiltration were determined from immunohistochemical staining.

RESULTS

Of the 229 retrospectively evaluated patients who underwent fat grafting, 22 had acne and had complete follow-up data; in these patients, the numbers of acne lesions were significantly lower after than before treatment. The 18 patients who received subdermal SVF-gel injection showed evident improvements in inflammatory lesions after more than 1 year of follow-up. CD4+ T-cell infiltration was significantly decreased at week 4.

CONCLUSIONS

Facial fat grafting can improve inflammatory acne lesions, perhaps because adipose-derived stem cells, which are plentiful in SVF-gel, reduce CD4+ T-cell-mediated inflammation responses.

LEVEL OF EVIDENCE: 4

Correction of the Tear Trough Deformity and Concomitant Infraorbital Hollows With Extracellular Matrix/Stromal Vascular Fraction Gel

BACKGROUND

The tear trough deformity is a sign of eye aging. Filling is an ideal choice for the tear trough accompanied by infraorbital hollows.

OBJECTIVE

To evaluate the efficacy and safety of stromal vascular fraction gel (SVF-gel) as a filler for the tear trough deformity which is combined with infraorbital hollows.

MATERIALS AND METHODS

From July 2017 to June 2018, 33 patients underwent autologous fat aspiration and were followed up successfully. Stromal vascular fraction gel was used to correct patients with bilateral Barton I/II; tear trough deformity and infraorbital hollows. Improvement was evaluated by measuring skin-periosteal depth, 3D volume, global aesthetic improvement scale (GAIS), and patient self-assessment.

RESULTS

Skin-periosteal depth improved significantly (p < .001). The volumetric increment of the tear trough and infraorbital regions increased 2.132 ± 0.671 mL, and the retention rate was excellent (72.87 ± 10.23%). The GAIS showed a high score (2.5 ± 0.5 points), with patient self-assessment showing satisfactory results for all 7 questions on the questionnaire.

CONCLUSION

The high retention rate of SVF-gel suggests that it can provide an effective solution to tear trough deformity accompanied by infraorbital hollows.

In-Vitro Comparative Examination of the Effect of Stromal Vascular Fraction Isolated by Mechanical and Enzymatic Methods on Wound Healing

BACKGROUND

Enzymatic digestion has been the gold standard for stromal vascular fraction (SVF) isolation but remains expensive and raises practical and legal concerns. Mechanical SVF isolation methods have been known to produce lower cell yields, but may potentially produce a more robust product by preserving the extracellular matrix niche.

OBJECTIVES

The aim of this study was to compare mechanically dissociated SVF (M-SVF) and enzymatically digested SVF (E-SVF) in terms of wound-healing efficacy.

METHODS

Lipoaspirate was partitioned into 2 equal groups and processed by either mechanical or enzymatic isolation methods. After SVF isolation, cell counts and viabilities were determined by flow cytometry and cell proliferation rates were measured by the WST-1 test. A wound-healing scratch assay test, which is commonly used to model in-vitro wound healing, was performed with both cell cocktails. Collagen type 1 (Col1A) gene expression level, which is known for its role in wound healing, was also measured for both groups.

RESULTS

As predicted, E-SVF isolated more cells (mean [standard deviation], 1.74 [3.63] × 106/mL, n = 10, P = 0.015) than M-SVF (0.94 [1.69] × 106/mL, n = 10, P = 0.015), but no significant difference was observed in cell viability. However, M-SVF expressed over 2-fold higher levels of stem cell surface markers and a 10% higher proliferation rate compared with E-SVF. In addition, the migration rate and level of Col1A gene expression of M-SVF were found to be significantly higher than those of E-SVF.

CONCLUSIONS

Although the cell yield of M-SVF was less than that of E-SVF, M-SVF appears to have superior wound-healing properties.

Engraftment of bioengineered three-dimensional scaffold from human amniotic membrane-derived extracellular matrix accelerates ischemic diabetic wound healing

Human amniotic membrane (HAM) is traditionally used for the treatment of non-healing wounds. However, high density of HAM-matrix (HAM-M) diminishes cellular contribution for successful tissue regeneration. Herein we investigated whether a bioengineered micro-porous three-dimensional (3D) HAM-scaffold (HAM-S) could promote healing in ischemic wounds in diabetic type 1 rat. HAM-S was prepared from freshly decellularized HAM. Then, 30 days after inducing diabetes, an ischemic circular excision was generated on rats' skin. The diabetic animals were randomly divided into untreated (Diabetic group), engrafted with HAM-M (D-HAM-M group) and HAM-S (D-HAM-S group). Also, non-diabeticuntreated rats (Healthy group) were considered as control. Stereological, molecular, and tensiometrical assessments were performed on post-surgical days 7, 14, and 21. We found that the volumes of new epidermis and dermis, the numerical density of epidermal basal cells and fibroblasts, the length density of blood vessels, the numbers of proliferating cells and collagen deposition as well as biomechanical properties of healed wound were significantly higher in D-HAM-S group in most cases compared those of the diabetic group, or even in some cases compared to D-HAM-M group. Furthermore, in D-HAM-S group, the transcripts for genes contributing to regeneration (Tgf-β, bFgf and Vegf) upregulated more than those of D-HAM-M group, when compared to diabetic ones. Overall, the HAM-S had more impact on delayed wound healing process compared to traditional use of intact HAM. It is therefore suggested that the bioengineered three dimensional micro-porous HAM-S is more suitable for cells adhesion, penetration, and migration for contributing to wounded tissue regeneration.

[Research progress of adipose-derived stem cells in promoting the repair of peripheral nerve injury]

Objective

To summarize the research progress of adipose-derived stem cells (ADSCs) in promoting the repair of peripheral nerve injury.

Methods

The related literature at home and abroad in recent years was widely reviewed, the mechanism of ADSCs promoting the repair of peripheral nerve injury was introduced, and its basic research progress was analyzed and summarized. Finally, the clinical transformation application of ADSCs in the treatment of peripheral nerve injury was introduced, the existing problems were pointed out, and the new treatment regimen was prospected.

Results

ADSCs have the function of differentiation and paracrine, and their secreted neurotrophic factors, antiapoptosis, and antioxidant factors can promote the repair of peripheral nerve injury.

Conclusion

ADSCs are rich in content and easy to obtain, which has a definite effectiveness on the repair of peripheral nerve injury with potential clinical prospect.

Role of stem cell therapies in treating chronic wounds: A systematic review

BACKGROUND

The impairment of cutaneous wound healing results in chronic, non-healing wounds that are caused by altered wound environment oxygenation, tissue injury, and permissive microbial growth. Current modalities for the treatment of these wounds inadequately address the complex changes involved in chronic wound pathogenesis. Consequently, stem cell therapies have emerged as a potential therapeutic modality to promote cutaneous regeneration through trophic and paracrine activity.

AIM

To investigate current literature regarding use of stem cell therapies for the clinical treatment of chronic, non-healing wounds.

METHODS

PubMed, EMBASE, Cochrane Library, Web of Science, and Scopus were queried with combinations of the search terms “mesenchymal stem cells,” “adult stem cells,” “embryonic stem cells,” “erythroid precursor cells,” “stem cell therapies,” and “chronic wounds” in order to find relevant articles published between the years of 2000 and 2019 to review a 20-year experience. Reference lists from the articles were reviewed to identify additional pertinent articles. Retrieved manuscripts (reviews, case reports/series, retrospective/prospective studies, and clinical trials) were evaluated by the authors for their depiction of clinical stem cell therapy use. Data were extracted from the articles using a standardized collection tool.

RESULTS

A total of 43 articles describing the use of stem cell therapies for the treatment of chronic wounds were included in this review. While stem cell therapies have been explored in in vitro and in vivo applications in the past, recent efforts are geared towards assessing their clinical role. A review of the literature revealed that adipose-derived stem cells, bone marrow-derived stem cells, bone marrow-derived mononuclear cells, epidermally-derived mesenchymal stem cells, fibroblast stem cells, keratinocyte stem cells, placental mesenchymal stem cells, and umbilical cord mesenchymal stem cells have all been employed in the treatment of chronic wounds of various etiologies. Most recently, embryonic stem cells have emerged as a novel stem cell therapy with the capacity for multifaceted germ cell layer differentiation. With the capacity for self-renewal and differentiation, stem cells can enrich existing cell populations in chronic wounds in order to overcome barriers impeding the progression of wound healing. Further, stem cell therapies can be utilized to augment cell engraftment, signaling and activity, and resultant patient outcomes.

CONCLUSION

Assessing observed clinical outcomes, potential for stem cell use, and relevant therapeutic challenges allows wound care stakeholders to make informed decisions regarding optimal treatment approaches for their patients’ chronic wounds.

A Concise Review on Tissue Engineered Artificial Skin Grafts for Chronic Wound Treatment: Can We Reconstruct Functional Skin Tissue In Vitro?

Chronic wounds occur as a consequence of a prolonged inflammatory phase during the healing process, which precludes skin regeneration. Typical treatment for chronic wounds includes application of autografts, allografts collected from cadaver, and topical delivery of antioxidant, anti-inflammatory, and antibacterial agents. Nevertheless, the mentioned therapies are not sufficient for extensive or deep wounds. Moreover, application of allogeneic skin grafts carries high risk of rejection and treatment failure. Advanced therapies for chronic wounds involve application of bioengineered artificial skin substitutes to overcome graft rejection as well as topical delivery of mesenchymal stem cells to reduce inflammation and accelerate the healing process. This review focuses on the concept of skin tissue engineering, which is a modern approach to chronic wound treatment. The aim of the article is to summarize common therapies for chronic wounds and recent achievements in the development of bioengineered artificial skin constructs, including analysis of biomaterials and cells widely used for skin graft production. This review also presents attempts to reconstruct nerves, pigmentation, and skin appendages (hair follicles, sweat glands) using artificial skin grafts as well as recent trends in the engineering of biomaterials, aiming to produce nanocomposite skin substitutes (nanofilled polymer composites) with controlled antibacterial activity. Finally, the article describes the composition, advantages, and limitations of both newly developed and commercially available bioengineered skin substitutes.

Diabetes-induced glucolipotoxicity impairs wound healing ability of adipose-derived stem cells-through the miR-1248/CITED2/HIF-1α pathway

Despite being an attractive cell type for mesenchymal stem cell (MSC) transplantation therapy for wound healing, human adipose-derived stem cells (hADSCs) from diabetes mellitus (DM) patients result in remarkable retention of stem cell activity due to diabetes-induced glucolipotoxicity. We explored the effect of diabetes and medium containing AGEs on the cell activity, phenotype, multipotency, angiogenic potential, and the therapeutic effect of hADSCs. Then, miRNA-1248 was selected by miRNA microarray analysis to further study the core molecular pathways that regulate the wound healing ability of hADSCs. hADSCs isolated from DM patients or cultured in medium containing AGEs in vitro exhibited decreased effectiveness in stem cell therapy. The expression of miRNA-1248 was decreased in the hADSCs of DM patients and hence failed to positively regulate stem cell activity, differentiation functions, and angiogenesis promotion effect. This concomitantly increased the expression of CITED2, an inhibitor of HIF-1α, thus influencing growth factors that promote angiogenesis, cellular proliferation, and wound healing. Overall, our data demonstrated that the glucolipotoxicity-impaired wound healing ability of hADSCs might occur through the miR-1248/CITED2/HIF-1α pathway. MiRNA-1248 may have potential to be used as a novel therapeutic target for wound healing in DM patients or restoring the wound healing ability of diabetic hADSCs.

Stromal vascular fraction promotes migration of fibroblasts and angiogenesis through regulation of extracellular matrix in the skin wound healing process

Background

A refractory wound is a typical complication of diabetes and is a common outcome after surgery. Current approaches have difficulty in improving wound healing. Recently, non-expanded stromal vascular fraction (SVF), which is derived from mature fat, has opened up new directions for the treatment of refractory wound healing. The aim of the current study is to systematically investigate the impact of SVF on wound healing, including the rate and characteristics of wound healing, ability of fibroblasts to migrate, and blood transport reconstruction, with a special emphasis on their precise molecular mechanisms.

Methods

SVF was isolated by digestion, followed by filtration and centrifugation, and then validated by immunocytochemistry, a MTS proliferation assay and multilineage potential analysis. A wound model was generated by creating 6-mm-diameter wounds, which include a full skin defect, on the backs of streptozocin-induced hyperglycemic mice. SVF or human adipose-derived stem cell (hADSC) suspensions were subcutaneously injected, and the wounds were characterized over a 9-day period by photography and measurements. A scratch test was used to determine whether changes in the migratory ability of fibroblasts occurred after co-culture with hADSCs. Angiogenesis was observed with human umbilical vein endothelial cells. mRNA from fibroblasts, endotheliocyte, and skin tissue were sequenced by high-throughput RNAseq, and differentially expressed genes, and pathways, potentially regulated by SVF or hADSCs were bioinformatically analyzed.

Results

Our data show that hADSCs have multiple characteristics of MSC. SVF and hADSCs significantly improved wound healing in hyperglycemic mice. hADSCs improve the migratory ability of fibroblasts and capillary structure formation in HUVECs. SVF promotes wound healing by focusing on angiogenesis and matrix remodeling.

Conclusions

Both SVF and hADSCs improve the function of fibroblast and endothelial cells, regulate gene expression, and promote skin healing. Various mechanisms likely are involved, including migration of fibroblasts, tubulogenesis of endothelial cells through regulation of cell adhesion, and cytokine pathways.

Conditioned medium from 3D culture system of stromal vascular fraction cells accelerates wound healing in diabetic rats

Aim: We investigated the healing effects of conditioned medium (CM) derived from a physiological 3D culture system engineered to use an extracellular matrix/stromal vascular fraction (SVF) gel enriched for adipose on diabetic wounds in rats. This CM (Gel-CM) was compared with that from a 2D culture system that used SVF cells (SVF-CM). Materials & methods: Keratinocytes, fibroblasts and wounds were treated with Gel-CM and SVF-CM, and cytokine levels in the CM types were quantified. Results: Proliferation and migration of keratinocytes and fibroblasts were significantly higher after treatment with Gel-CM than with SVF-CM. Collagen secretion by fibroblasts and wound closure were highly stimulated by Gel-CM. Proteomic analyses revealed a higher concentration of growth factors in Gel-CM than in SVF-CM. Conclusion: Gel-CM is a promising therapeutic option for treating diabetic wounds.

Optically Transparent Anionic Nanofibrillar Cellulose Is Cytocompatible with Human Adipose Tissue-Derived Stem Cells and Allows Simple Imaging in 3D

The anti-inflammatory and immunomodulatory properties of human mesenchymal stromal cells (MSCs) are a focus within regenerative medicine. However, 2D cultivation of MSCs for extended periods results in abnormal cell polarity, chromosomal changes, reduction in viability, and altered differentiation potential. As an alternative, various 3D hydrogels have been developed which mimic the endogenous niche of MSCs. Nevertheless, imaging cells embedded within 3D hydrogels often suffers from low signal-to-noise ratios which can be at least partly attributed to the high light absorbance and light scattering of the hydrogels in the visible light spectrum. In this study, human adipose tissue-derived MSCs (ADSCs) are cultivated within an anionic nanofibrillar cellulose (aNFC) hydrogel. It is demonstrated that aNFC forms nanofibres arranged as a porous network with low light absorbance in the visible spectrum. Moreover, it is shown that aNFC is cytocompatible, allowing for MSC proliferation, maintaining cell viability and multilineage differentiation potential. Finally, aNFC is compatible with scanning electron microscopy (SEM) and light microscopy including the application of conventional dyes, fluorescent probes, indirect immunocytochemistry, and calcium imaging. Overall, the results indicate that aNFC represents a promising 3D material for the expansion of MSCs whilst allowing detailed examination of cell morphology and cellular behaviour.

Stromal vascular fraction technologies and clinical applications

Introduction: The heterogeneous pool of cells found in the stromal vascular fraction of adipose tissue (SVF) and the purified mesenchymal stromal/stem cells (ASCs) isolated from this pool have increasingly been used as therapeutic tools in regenerative medicine.Areas covered: As SVF and ASCs are different, and should be used in different manners according to various clinical and biological indications, we reviewed the current literature, and focused on the clinical use of SVF to appraise the main medical fields for development. Both enzymatic digestion and mechanical disruption have been used to obtain SVF for non-homologous use. The safety and/or benefits of SVF have been examined in 71 clinical studies in various contexts, mainly musculoskeletal conditions, wound healing, urogenital, and cardiovascular and respiratory diseases. The use of SVF as a therapy remains experimental, with few clinical trials.Expert opinion: SVF provides a cellular and molecular microenvironment for regulation of ASC' activities under different clinical conditions. SVF may enhance angiogenesis and neovascularization in wound healing, urogenital and cardiovascular diseases. In joint conditions, therapeutic benefits may rely on paracrine immune-modulatory and anti-inflammatory mechanisms. Novel point of care methods are emerging to refine SVF in ways that meet the regulatory requirements for minimal manipulation.

Human adipose liquid extract induces angiogenesis and adipogenesis: a novel cell-free therapeutic agent

BACKGROUND

Taking advantage of cellular paracrine mechanisms, the secretome of adipose-derived stem cells (ADSCs) and adipose tissue has been demonstrated to induce tissue repair and regeneration in various ischemic and impaired conditions. However, these cell-based therapies have been hindered by issues, such as inherent safety and cost-efficiency for clinical applications. In this study, we prepared a liquid cell-free extract from human adipose tissue [adipose liquid extract (ALE)] and evaluated its potential therapeutic efficacy.

METHODS

ALE was prepared from human subcutaneous adipose tissue using a rapid and physical approach, and the protein components in ALE were identified using mass spectrometry analysis. In vivo, the therapeutic effect of this agent was investigated on wound healing in C57BL/6 mice, and wound healing rate, vessel density, and neo-adipocyte formation in wounded skins were measured at days 3, 7, 11, and 14. In vitro, the effect of ALE on the viability of human ADSCs, tube formation of human umbilical vein endothelial cells (HUVECs), and adipogenic differentiation of ADSCs were tested.

RESULTS

The results demonstrated that ALE contained a variety of growth factors and did not affect cell viability. ALE-treated wounds exhibited accelerated wound healing with increased vessel density and formation of neo-adipocytes compared to that of control wounds. Moreover, when added as a cell culture supplement, ALE effectively induced tube formation of HUVECs and lipid accumulation in ADSCs. ALE-treated ADSCs also exhibited elevated levels of adipogenic gene expression.

CONCLUSIONS

ALE is a novel growth-rich therapeutic agent that is cell-free and easy to produce. Besides, it is also able to induce angiogenesis and adipogenesis both in vitro and in vivo, thus indicating that it could be used for wound repair and soft tissue regeneration.

Efficacy of Injection of Freshly Collected Autologous Adipose Tissue Into Perianal Fistulas in Patients With Crohn's Disease

BACKGROUND & AIMS

Perianal fistulas are common in patients with Crohn's disease (CD). Injections of cultured autologous and allogeneic adipose tissue-derived stem cells have been shown to heal CD-associated fistulas. Unfortunately, this treatment is time consuming and expensive. We investigated the effects of injecting freshly collected autologous adipose tissue into perianal fistulas in patients with CD.

METHODS

In a prospective interventional study, freshly collected autologous adipose tissues were injected into complex perianal fistulas of 21 patients with CD, from March 2015 through June 2018. The primary endpoint was complete fistula healing (no symptoms of discharge, no visible external fistula opening in the perineum, and no internal opening detected by rectal digital examination) 6 months after the last injection. We performed pelvic magnetic resonance imaging to confirm fistula resolution in patients with intersphincter and transsphincter fistulas who showed complete healing at clinical examination. Patients without complete fistula healing after 6 weeks and those with later relapse were offered additional injections. No control individuals were included.

RESULTS

Six months after the last adipose tissue injection, 12 patients (57%) had complete fistula healing. Three patients (14%) had ceased fistula secretion, and 1 patient (5%) reported reduced secretion. Among 10 patients with trans-sphincter or inter-sphincter fistulas, magnetic resonance imaging showed complete fistula resolution in 9 patients and a markedly reduced gracile fistula in the remaining patient. Of the 12 patients with complete fistula healing, 9 (43%) required 1 injection, 2 (10%) required 2 injections, and 1 (5%) required 3 injections. The predominant adverse effect was postprocedure proctalgia lasting a few days. Two patients developed small abscesses, 1 had urinary retention, and 1 had minor bleeding during liposuction.

CONCLUSION

In a study of 21 patients with CD and perianal fistulas, we found injection of recently collected autologous adipose tissue to be safe and to result in complete fistula healing in 57% of patients. ClinicalTrials.gov, Number: NCT03803917.

Intratunical Injection of Human Adipose Tissue-Derived Stem Cells Restores Collagen III/I Ratio in a Rat Model of Chronic Peyronie's Disease

Introduction

Previous studies have shown that the injection of adipose tissue–derived stem cells (ADSCs) into the tunica albuginea (TA) during the active phase of Peyronie’s disease (PD) prevents the development of fibrosis.

Aim

To investigate, using an animal model, whether local injection of human ADSCs (hADSCs) can alter the degree of fibrosis in the chronic phase of PD.

Methods

27 male, 12-week-old rats were divided into 3 equal groups: sham, PD without treatment, and PD treated with hADSCs 1 month after disease induction. Sham rats underwent 2 injections of vehicle into the TA 1 month apart. PD rats underwent transforming growth factor β1 (TGFβ1) injection and injection of vehicle 1 month later. PD-hADSC rats underwent TGFβ1 injection followed by 1 million hADSCs 1 month later. 1 week after treatment, n = 3 animals/group were euthanized, and the penises were harvested for quantitative polymerase chain reaction. 1 month after treatment, the other animals, n = 6 per group, underwent measurement of intracavernous pressure (ICP) and mean arterial pressure (MAP) during electrostimulation of the cavernous nerve. After euthanasia, penises were again harvested for histology and Western blot.

Main Outcome Measure

The primary outcome measures included (a) gene expression at one week post-injection; (b) measurement of ICP/MAP upon cavernous nerve stimulation as a measure of erectile function; (c) elastin, collagen I and III protein expression; and (d) Histomorphometric analysis of the penis. Means where compared by analysis of variance (ANOVA) followed by a Student-Newman-Keuls test for post hoc comparisons or Mann-Whitney test when applicable.

Results

No significant difference was noted in ICP or ICP/MAP in response to cavernous nerve electrostimulation between the 3 groups at 2.5, 5, and 7.5 V (P > .05 for all voltages). PD animals developed tunical and subtunical areas of fibrosis with a significant upregulation of collagen III protein. The collagen III/I ratio was higher in the PD (4.6 ± 0.92) group compared with sham (0.66 ± 0.18) and PD-hADSC (0.86 ± 0.06) groups (P < .05) These fibrotic changes were prevented when treated with hADSCs. Compared with PD rats, PD-hADSC rats demonstrated a decreased expression of several fibrosis-related genes.

Conclusion

Injection of hADSCs reduces collagen III expression in a rat model of chronic PD.

Castiglione F, Hedlund P, Weyne E, et al. Intratunical Injection of Human Adipose Tissue–Derived Stem Cells Restores Collagen III/I Ratio in a Rat Model of Chronic Peyronie’s Disease. Sex Med 2019;7:94–103.