Evaluation of autologous adipose-derived stem cells vs. fractional carbon dioxide laser in the treatment of post acne scars: a split-face study

Insights into the role of adipose-derived stem cells and secretome: potential biology and clinical applications in hypertrophic scarring

Scar tissue is the inevitable result of repairing human skin after it has been subjected to external destructive stimuli. It leads to localized damage to the appearance of the skin, accompanied by symptoms such as itching and pain, which reduces the quality of life of the patient and causes serious medical burdens. With the continuous development of economy and society, there is an increasing demand for beauty. People are looking forward to a safer and more effective method to eliminate pathological scarring. In recent years, adipose-derived stem cells (ADSCs) have received increasing attention from researchers. It can effectively improve pathological scarring by mediating inflammation, regulating fibroblast proliferation and activation, and vascular reconstruction. This review focuses on the pathophysiological mechanisms of hypertrophic scarring, summarizing the therapeutic effects of in vitro, in vivo, and clinical studies on the therapeutic effects of ADSCs in the field of hypertrophic scarring prevention and treatment, the latest application techniques, such as cell-free therapies utilizing ADSCs, and discussing the advantages and limitations of ADSCs. Through this review, we hope to further understand the characterization of ADSC and clarify the effectiveness of its application in hypertrophic scarring treatment, so as to provide clinical guidance.

Autologous Nanofat Injection Combined with Fractional CO2 Laser in the Treatment of Atrophic Acne Scars

Background

Atrophic acne scarring is a widely prevalent condition and one of the most distressing complications of acne vulgaris. Numerous options with variable outcomes are available for the treatment of acne scarring. Laser is considered a first-line therapy for acne scars, and recently there has been a growing interest in using stem cells and their derivatives for treating acne scars. In addition, combined therapeutic modalities often achieve more satisfactory results than a single treatment.

Objective

We tried to evaluate the role of nanofat and fractional CO2 laser as a combined treatment approach for atrophic acne scarring.

Methods

Twenty-five patients with atrophic acne scarring were enrolled. They received a single session of intradermal nanofat injection, at different points 1 cm apart, for acne scars. Two weeks later, they were treated with three sessions of fractional CO2 laser at monthly intervals. Patients were evaluated three months after the last session using the quantitative Goodman and Baron scoring system. Pain, side effects, and patients' satisfaction were also evaluated.

Results

There were two males and 23 females with a mean age of 25.96 years. Their skin type ranged between Fitzpatrick skin type III, IV, and V. Boxcar scars were the most common scar type in 13 patients (52%). After treatment, there was a significant reduction (p <0.05) in the quantitative Goodman and Baron scores. The improvement was more evident in rolling scars. Seven patients reported significant improvement, and 12 reported marked improvement.

Conclusion

This study showed that combining nanofat and fractional CO2 laser is a safe and effective treatment modality for atrophic acne scars.

Atrophic Postacne Scar Treatment: Narrative Review

Acne scarring is a frequent complication of acne. Scars negatively impact psychosocial and physical well-being. Optimal treatments significantly improve the appearance, quality of life, and self-esteem of people with scarring. A wide range of interventions have been proposed for acne scars. This narrative review aimed to focus on facial atrophic scarring interventions. The management of acne scarring includes various types of resurfacing (chemical peels, lasers, and dermabrasion); the use of injectable fillers; and surgical methods, such as needling, punch excision, punch elevation, or subcision. Since the scarred tissue has impaired regeneration abilities, the future implementation of stem or progenitor regenerative medical techniques is likely to add considerable value. There are limited randomized controlled trials that aimed to determine which treatment options should be considered the gold standard. Combining interventions would likely produce more benefit compared to the implementation of a single method.

Fractional CO 2 Laser Combined With Autologous Nanofat Injection Versus Fractional CO 2 Laser Combined With Platelet-Rich Plasma in the Treatment of Atrophic Acne Scars: A Split-Face Comparative Study With Optical Skin Imaging

BACKGROUND

Atrophic acne scarring is a common problem. If left untreated, its implications can impair the quality of life. Various treatments, with differing degrees of success, are used to alleviate atrophic scars.

OBJECTIVE

To assess the efficacy of nanofat versus platelet-rich plasma (PRP) as an adjuvant therapy to fractional CO 2 laser (FCL) for atrophic acne scars.

METHODS

This study included 35 patients with atrophic acne scars who received 3 sessions of FCL at 1-month intervals on both sides of the face, followed by intradermal PRP injection on the left side. A single session of nanofat was injected into the right side of the face 2 weeks before the laser sessions. The evaluation was conducted 3 months after the final treatment session.

RESULTS

After treatment, the right side of the face showed a significant reduction in Goodman scores and the indentation index of the Antera camera. The left side showed a significant difference in Goodman scores, yet the Antera camera showed a nonsignificant improvement. Nonetheless, the difference between the 2 sides was statistically insignificant.

CONCLUSION

Atrophic acne scars improved with both modalities. As a result, cotreatment with these techniques may synergistically affect atrophic acne scars in efficacy and safety.

Advancements in adipose-derived stem cell therapy for skin fibrosis

Pathological scarring and scleroderma, which are the most common conditions of skin fibrosis, pathologically manifest as fibroblast proliferation and extracellular matrix (ECM) hyperplasia. Fibroblast proliferation and ECM hyperplasia lead to fibrotic tissue remodeling, causing an exaggerated and prolonged wound-healing response. The pathogenesis of these diseases has not been fully clarified and is unfortunately accompanied by exceptionally high medical needs and poor treatment effects. Currently, a promising and relatively low-cost treatment has emerged-adipose-derived stem cell (ASC) therapy as a branch of stem cell therapy, including ASCs and their derivatives-purified ASC, stromal vascular fraction, ASC-conditioned medium, ASC exosomes, etc., which are rich in sources and easy to obtain. ASCs have been widely used in therapeutic settings for patients, primarily for the defection of soft tissues, such as breast enhancement and facial contouring. In the field of skin regeneration, ASC therapy has become a hot research topic because it is beneficial for reversing skin fibrosis. The ability of ASCs to control profibrotic factors as well as anti-inflammatory and immunomodulatory actions will be discussed in this review, as well as their new applications in the treatment of skin fibrosis. Although the long-term effect of ASC therapy is still unclear, ASCs have emerged as one of the most promising systemic antifibrotic therapies under development.

Efficacy and Safety of Transplantation of Autologous Fat, Platelet-Rich Plasma (PRP) and Stromal Vascular Fraction (SVF) in the Treatment of Acne Scar: Systematic Review and Meta-analysis

BACKGROUND

The efficacy and safety evaluation of the transplantation of autologous fat, platelet-rich plasma (PRP) and stromal vascular fraction (SVF) in acne scars has not been completely unified. This article will analyze and process the data of the included studies through evidence-based medicine to evaluate the efficacy and safety of autologous fat grafting, PRP and SVF for acne scar treatment, so as to provide treatment basis and strategy for the clinical treatment of acne scars.

METHODS

We searched the PubMed, Embase, Cochrane Library databases, CNKI, Wanfang and CQVIP databases for studies published during the time between the establishment of the databases through October 2022. We included studies that report autologous fat grafting, SVF and PRP for patients with acne scars. We excluded repeated publication, researches without full text, incomplete information or inability to conduct data extraction and animal experiments, case report, reviews and systematic reviews. STATA 15.1 software was used to analyze the data.

RESULTS

The findings showed that fat grafting had excellent improvement, marked improvement, moderate improvement and mild improvement rates of 36%, 27%, 18% and 18%, respectively, PRP had excellent improvement, marked improvement, moderate improvement and mild improvement rates of 0%, 26%, 47% and 25%, respectively, and the SVF had excellent improvement, marked improvement, moderate improvement and mild improvement rates of 73%, 25%, 3% and 0%, respectively. Additionally, the pooled results showed that there was no significant difference between PRP treatment and pre-treatment in Goodman and Baron scale score. However, Shetty et al. reported that Goodman and Baron scale score after fat grafting was significantly lower than pre-treatment. The results also showed that after fat grafting treatment, incidence of pain after fat grafting was 70%. After PRP treatment, in addition to pain (17%), there is a higher probability of postinflammatory hyperpigmentation (17%) and hematoma (6%). After SVF treatment, the incidence of postinflammatory hyperpigmentation and hematoma was all 0%.

CONCLUSION

Autologous fat grafting, PRP and SVF are effective for the treatment of acne scars, and the safety of autologous fat grafting, PRP and SVF is acceptable. Autologous fat grafting and SVF may be a better treatment for acne scars than PRP. However, this hypothesis still needs to be tested in the future large randomized controlled trials.

LEVEL OF EVIDENCE III

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 .

Therapeutic potential of adipose tissue-derivatives in modern dermatology

Stem cell-mediated therapies in combination with biomaterial and growth factor-based approaches in regenerative medicine are rapidly evolving with increasing application beyond the dermatologic field. Adipose-derived stem cells (ADSCs) are the more frequently used adult stem cells due to their abundance and easy access. In the case of volumetric defects, adipose tissue can take the shape of defects, restoring the volume and enhancing the regeneration of receiving tissue. When regenerative purposes prevail on volume restoration, the stromal vascular fraction (SVF) rich in staminal cells, purified mesenchymal stem cells (MSCs) or their cell-free derivatives grafting are favoured. The therapeutic efficacy of acellular approaches is explained by the fact that a significant part of the natural propensity of stem cells to repair damaged tissue is ascribable to their secretory activity that combines mitogenic factors, cytokines, chemokines and extracellular matrix components. Therefore, the secretome's ability to modulate multiple targets simultaneously demonstrated preclinical and clinical efficacy in reversing pathological mechanisms of complex conditions such atopic dermatitis (AD), vitiligo, psoriasis, acne and Lichen sclerosus (LS), non-resolving wounds and alopecia. This review analysing both in vivo and in vitro models gives an overview of the clinical relevance of adipose tissue-derivatives such as autologous fat graft, stromal vascular fraction, purified stem cells and secretome for skin disorders application. Finally, we highlighted the major disease-specific limitations and the future perspective in this field.

Evaluating the effectiveness of stromal-vascular fraction (SVF) cells along with subcision method in the treatment of acne scars: A double-blind randomized controlled clinical trial study

BACKGROUND

Subcision method is one of the main techniques for treatment of acne scars or stromal-vascular fraction (SVF) and combined therapy can improve treatment strategy.

OBJECTIVE

To use subcision method along with SVF for treatment of acne scar and comprised with alone subcision method.

MATERIALS AND METHODS

In this double-blind clinical trial study, 10 patients with acne scars were entered into the study. Subcision technique was randomly performed on one side of the face and subcision technique plus SVF on opposite side of the face. All patients were examined before treatment and after 3 months by Visioface for volume, area, and depth of scars, as well as thickness and density of the epidermis and dermis of the scars in question. In addition, doctor's and patients' satisfaction, tolerability, and safety were determined after 3 months of treatment. Finally, statistical analysis was done by SPPS, version 25.

RESULTS

In terms of volume and area of scars, the mean percent change was 46.55 ± 13.92 and 44.60 ± 5.76, for the case group, and 13.31 ± 9.27 and 11.28 ± 9.64 for the control group, respectively. So, combined therapy led to significant recovery compared with alone subcision method (p value < 0.001). In both interventions, the increase of density and thickness was proven after treatment, also a significant difference in complete, epidermal, and dermal thickness and epidermal density variables was observed between combined therapy and alone subcision (p value < 0.05). Mean score of doctor's and patients' satisfaction in combined therapy (7.10 ± 0.74 and 7.10 ± 0.99, respectively), was also significantly higher than subcision alone (5.50 ± 0.53 and 5.30 ± 1.25, respectively). Finally, no complications were observed in the patients.

CONCLUSION

According to the acquired results, combined therapy can be considered as effective and safe treatment for acne scars with significant higher efficacy compared with subcision alone.

Adipose-derived stem cells attenuate acne-related inflammation via suppression of NLRP3 inflammasome

BACKGROUND

Acne is a chronic facial disease caused by Propionibacterium acnes, which proliferates within sebum-blocked skin follicles and increases inflammatory cytokine production. Several therapeutic drugs and products have been proposed to treat acne, yet no single treatment that ensures long-term treatment efficacy for all patients is available. Here, we explored the use of facial autologous fat transplant of adipose-derived stem cells (ADSCs) to dramatically reduce acne lesions.

METHODS

THP-1 cells were treated with active P. acnes for 24 h at different multiplicities of infection, and alterations in inflammatory factors were detected. To study the effect of THP-1 on inflammasome-related proteins, we first co-cultured ADSCs with THP-1 cells treated with P. acnes and evaluated the levels of these proteins in the supernatant. Further, an acne mouse model injected with ADSCs was used to assess inflammatory changes.

RESULTS

Propionibacterium acnes-mediated stimulation of THP-1 cells had a direct correlation with the expression of active caspase-1 and interleukin (IL)-1β in an infection-dependent manner. ADSCs significantly reduced the production of IL-1β induced by P. acnes stimulation through the reactive oxygen species (ROS)/Nod-like receptor family pyrin domain-containing 3 (NLRP3)/caspase-1 pathway. The results showed that ADSCs inhibit the skin inflammation induced by P. acnes by blocking the NLRP3 inflammasome via reducing the secretion of IL-1β in vivo.

CONCLUSIONS

Our findings suggest that ADSCs can alter IL-1β secretion by restricting the production of mitochondria ROS, thereby inhibiting the NLRP3/caspase-1 pathway in P. acnes-induced inflammatory responses. This study indicates that anti-acne therapy can potentially be developed by targeting the NLRP3 inflammasome.

The investigation of the efficacy and safety of stromal vascular fraction in the treatment of nanofat-treated acne scar: a randomized blinded controlled clinical trial

Background

Acne is the most common skin disorder which is known as a chronic inflammatory disease with psychological burden and reduced quality of life. Adipose tissue-derived stromal vascular fraction (SVF) is recognized as a source of regenerative cells and improves the quality of skin by increasing collagen content. To date, a few studies have been performed on the therapeutic role of SVF in the treatment of acne scars.

Methods

This randomized, single-blinded clinical trial was performed on 7 patients with acne scars. In all patients, the initial grade of acne (volume, area and depth) was evaluated and ultrasound of the relevant scar was performed to evaluate neocollagenesis. As a spilt face study, for treating the scars, we used nanofat subcutaneously on one side of the face (control group) and combination of nanofat subcutaneously and SVF intradermally on the opposite side (intervention group). The patients were evaluated for severity of acne by visioface after one month, also for thickness of epidermis and dermis by ultrasound after one month and three months.

Results

All of the apparent findings of scars improved in two groups after one month, but these changes were significant just for the group treated with SVF (p value < 0.05). Epidermal, dermal and complete thicknesses during the first month in both control and intervention groups were significantly increased (p value < 0.05) but between the first and third months, there was no significant difference in the variables (p value > 0.05). The findings showed that dermal and complete thicknesses of the skin in the first month were different between two groups significantly (p value: 0.042 and 0.040, respectively).

Conclusion

The use of SVF in the treatment of patients with acne scars accelerates the improvement of volume, area and depth of the scar by increasing collagen content and the dermal thickness, so it can be used as a potentially effective treatment for these patients.

Stromal vascular fraction improves the durability of autologous fat temple augmentation-A split-face randomized study using ultrasound biomicroscopy

BACKGROUND

Autologous lipotransfer aims to restore aging-associated volume loss, but with low predictability owing to 20-90% first-year loss of transferred fat. Enrichment by adipose-derived stem cells within the stromal vascular fraction (SVF) aims to improve volume retention through their differentiation potential and paracrine actions exerted by secreted trophic and angiogenic factors. Assessing studies lacked split-face designs, and used multitudes of enrichment ratios, preparation techniques and evaluation methods ending in contradictory reports regarding enrichment advantage.

AIM

To test whether enriching the autologous fat graft with SVF will increase its residual volume as compared to non-enriched graft. A standardized enrichment protocol and ratio and objective assessment were employed.

PATIENTS AND METHODS

In a split-face design, and after random assignment, bilateral temple augmentation using non-enriched versus SVF-enriched autologous lipotransfer were compared in middle-aged females otherwise healthy non-pregnant or breast-feeding females abstaining from esthetic or weight-controlling procedures. Temple volume scale (TVS), skin layers' thickness measured by ultrasound biomicroscopy (UBM), visual analog scale for patients' satisfaction, and side effects were blindly assessed at 1 week, 3 months, and 6 months.

RESULTS

In the included 15 females, TVS was significantly lower (0.5 ± 0.5 versus 1.1 ± 0.7, P = 0.0001), and% hypodermal augmentation was significantly higher (70.92 ± 58.09 versus 18.93 ± 19.33, P = 0.001) on the SVF-enriched side at 6 months. Patient satisfaction was similar bilaterally (P = 1), as were sequelae frequencies as lumping, edema, and ecchymosis.

CONCLUSION

SVF enrichment of transferred fat significantly improved its residual volume at 6 months; a conclusion that needs further validation. UBM was an informative objective tool for the following temple skin thickness changes. Trial registration clinical trials.gov (NCT03965936).

Application of adipose-derived stem cells in treating fibrosis

Fibrosis is the hyperactivation of fibroblasts that results in excessive accumulation of extracellular matrix, which is involved in numerous pathological changes and diseases. Adipose-derived stem cells (ASCs) are promising seed cells for regenerative medicine due to their bountiful source, low immunogenicity and lack of ethical issues. Their anti-fibrosis, immunomodulation, angiogenesis and other therapeutic effects have made them suitable for treating fibrosis-related diseases. Here, we review the literature on ASCs treating fibrosis, elaborate and discuss their mechanisms of action, changes in disease environment, ways to enhance therapeutic effects, as well as current preclinical and clinical studies, in order to provide a general picture of ASCs treating fibrotic diseases.

The Use of Adipose-Derived Stem Cells (ADSCs) and Stromal Vascular Fraction (SVF) in Skin Scar Treatment-A Systematic Review of Clinical Studies

In recent years, lipofilling became a popular scar treatment method. Its beneficial outcomes have been partly attributed to the regenerative capacity of adipose-derived stem cells (ADSCs), suspended in an extracellular matrix-the stromal vascular fraction (SVF). The aim of this review was to verify if existing data support the clinical use of ADSC-related interventions in scar treatment. A systematic search of the literature was performed in July 2020 in five databases (Medline, Cochrane, Web of Science, Scopus and Embase). Articles written in English, except for reviews, letters and editorials, were identified and screened for eligibility. We looked for reports of any outcomes in scars treated with ADSCs or SVF. Data from selected articles were extracted and the quality of each study was assessed. Five hundred and fourteen studies were identified in the primary search, of which nineteen were eventually included in the systematic review. Extracted data pointed to beneficial microscopic, functional and aesthetic outcomes in a total of 665 patients. Six studies included comparative interventions-platelet-rich plasma or CO2 fractional laser. Collected data give low-to-average quality evidence for beneficial effects of ADSC-related interventions in scar treatment. Some studies suggest that these interventions are noninferior to PRP or fractional CO2 laser.

Transplantation of autologous fat, stromal vascular fraction (SVF) cell, and platelet-rich plasma (PRP) for cell therapy of atrophic acne scars: Clinical evaluation and biometric assessment

BACKGROUND

Scarring is an unfortunate result of acne because it causes the psychological and cosmetic problems for the patients. Unfortunately, no single treatment is suitable, and using multiple methods may have a better result. The autologous fat and stromal vascular fraction (SVF) cells and their secretory factors can enhance the angiogenesis, collagen synthesis, and migration of fibroblasts, therefore regenerate hurt tissues. Moreover, other treatments for acne scarring, such as platelet-rich plasma (PRP), induce the increase in scare.

AIMS

This study aimed to verify the effectiveness of transplantation of autologous fat, SVF cells, and PRP as cell therapy techniques on atrophic acne scars.

PATIENTS/METHODS

This study included 9 adult patients with atrophic acne scars on face. All patients received the transplantation of autologous fat, stromal vascular fraction (SVF) cells, and PRP. The treatment outcome was measured by biometric assessment (VisioFace 1000 D, Colorimeter, multi-probe adapter Cutometer, Tewameter, Mexameter, and skin ultrasound imaging system), and also, the satisfaction of patients was evaluated. The patients were followed 6 months after the treatment.

RESULTS

There was a significant improvement in the skin pores, spots, skin lightness and melanin content of skin, skin elasticity, and TEWL (transepidermal water loss) after 6 months of the treatment. Furthermore, denser skin layers were observed both in the epidermis and in the dermis. Moreover, 66.6% of patients showed good satisfaction after the treatment.

CONCLUSION

In brief, the transplantation of autologous fat, SVF cells, and PRP is an effective cell therapy for atrophic acne scars.

Treatment of atrophic acne scars: Topical or intralesional plasma gel?

BACKGROUND

Atrophic post-acne scarring is considered to be a therapeutic challenge.

OBJECTIVES

The aim was to compare the safety and efficacy of (A) FCL combined with intradermal injection of plasma gel, (B) FCL combined with topical application of plasma gel, and (C) FCL monotherapy in the treatment of atrophic post-acne scars.

METHODS

Thirty patients with facial atrophic post-acne scars were enrolled in this study and randomly assigned into one of three groups. All of them underwent four treatment sessions at 4-weeks intervals. They were assessed objectively by the quantitative global scarring grading system (GSGS). This system was applied at baseline, and after 1- and 6-month follow-up (FU). Subjective assessments were performed through the global esthetic improvement scale (GAIS) and level of patient satisfaction. The DLQI questionnaire was employed at the baseline and 6-month FU.

RESULTS

According to the quantitative GSGS scores, the reductions in group A (68.4%) and group B (63%) scores were comparable, and both were significantly higher than that in group C (41.2%) in all steps of evaluation. At 6-month FU, both groups A and B showed further significant improvement, while group C did not. Based on the GAIS and patients' satisfaction, there were no significant differences between all groups. The reductions in DLQI scores in groups A and B were comparable; however, both were significantly higher than group C (P < .001).

CONCLUSIONS

The combination of plasma gel and FCL resurfacing was noticeably outstanding in their efficacy and impact on the patients' quality of life.

Systematic review: Advances of fat tissue engineering as bioactive scaffold, bioactive material, and source for adipose-derived mesenchymal stem cells in wound and scar treatment

Fat tissue (FT) has been used for many years in regenerative surgery as a bioactive material through the lipofilling/fat graft (F-GRF)-nano-fat technique, as a bioactive scaffold when it was enriched with adipose-derived mesenchymal stem cells (AD-MSCs) contained in the stromal vascular fraction (SVF), and as a direct source of AD-MSCs used in wound healing (WH) and scar treatment (ST). This systematic review aims to describe the advances in FT engineering applied to regenerative surgery (from bench to clinic), through the use of AD-MSCs, SVF contained in F-GRF in WH and ST. The work has been performed by assessing in the selected studies autologous graft of AD-MSCs, SVF, and F-GRF compared to any control for ST and WH. The protocol was developed following the Preferred Reporting for Items for Systematic Reviews and Meta-Analyses-Protocols (PRISMA-P) guidelines. A multistep search of the PubMed, MEDLINE, Embase, PreMEDLINE, Ebase, CINAHL, PsycINFO, Clinicaltrials.gov , Scopus database, and Cochrane databases has been performed to identify papers on AD-MSCs, SVF, and F-GRF use in WH and ST in which FT was used as bioactive material-scaffold and source of AD-MSCs. Of the 714 articles initially identified, 453 articles focusing on regenerative strategies in WH and ST were selected and, consequently, only 84 articles that apparently related to AD-MSC, SVF, and F-GRF were analyzed. Of these, 61 articles identified as pre-clinical, experimental, and in vitro, and 5 articles identified as a comment and systematic review were excluded. Only 18 original articles which strictly and exclusively focused on autologous AD-MSCs, SVF, and F-GRF in ST and WH were analyzed. The included studies had to match predetermined criteria according to the PICOS (patients, intervention, comparator, outcomes, and study design) approach. The identified studies described microscopic and clinical outcomes in patients treated with AD-MSCs, SVF, and F-GRF. Collected data confirmed the safety and efficacy of FT both as bioactive material-scaffold and source of AD-MSCs in WH and ST without major side effects.

Update on the role of emerging stem cell technology in head and neck medicine

Head and neck surgery is a broad discipline that involves the management of complex conditions such as burns, skin cancer, head and neck cancer, congenital abnormalities, and facial rejuvenation. For patients with cancer, surgery, radiotherapy, and chemotherapy are often the main modes of treatment. Many patients require follow-up reconstructive surgery, and the use of stem cells offers novel treatments that could aid recovery. Laryngeal, tracheal, and neuronal tissues are frequently damaged by surgery in the head and neck and these tissues have little intrinsic regenerative ability. Pluripotent embryonic stem cells retain the ability to differentiate into a wide variety of cells meaning that large tissue defects can be reduced by stimulating new cell growth. Research has demonstrated potential benefits of using stem cells in facial rejuvenation procedures and the management of burns sequelae. The advancements made in the use of adult progenitor stem cells as a possible source for pluripotent stem cells (induced pluripotent stem cells) mean that ethical considerations around the use of embryological tissue can be minimized, allowing for more research to take place. Currently, the evidence base for the use of stem cells in head and neck surgery is limited, but it has now been proven that stem cells can act as a source for lost or damaged tissue in the head and neck. With continuous advancements being made in the fields of tissue engineering, it is likely that stem cells will play a major role in head and neck surgery in the future.

The efficacy of fractional CO2 laser in acne scar treatment: A meta-analysis

Fractional CO₂ laser is a good option for treating acne scars. However, the clinical efficacy of this treatment modality requires further evidence. To perform a meta-analysis to assess clinical improvements in acne scars with fractional CO₂ laser and non-CO₂ laser therapies. Databases (PubMed, Embase, Cochrane Library) were searched using the search strategy to identify eligible studies. All statistical analyses were performed using the Review Manager 5.0, and a meta-analysis was conducted to assess the effects of fractional CO₂ laser used as a treatment for acne scars. Eight studies were included for further analysis. There was no significant difference between fractional CO₂ laser and non-CO₂ laser therapies in terms of clinical improvement, observer assessment (P = .19), patient assessment (P = .91), and incidence of post-inflammatory hyperpigmentation (P = .69). The subgroup analyses showed that the duration of follow-up had little effect on the evaluation of treatment effect. The efficacy of fractional CO₂ laser therapy in acne scars appeared to be equal to that of non-CO₂ laser therapies. More well designed randomized controlled trials and more credible and standard evaluation criteria are needed, and the efficiency of combination therapy requires further analysis.

Adipose Tissue Fibrosis: Mechanisms, Models, and Importance

Increases in adipocyte volume and tissue mass due to obesity can result in inflammation, further dysregulation in adipose tissue function, and eventually adipose tissue fibrosis. Like other fibrotic diseases, adipose tissue fibrosis is the accumulation and increased production of extracellular matrix (ECM) proteins. Adipose tissue fibrosis has been linked to decreased insulin sensitivity, poor bariatric surgery outcomes, and difficulty in weight loss. With the rising rates of obesity, it is important to create accurate models for adipose tissue fibrosis to gain mechanistic insights and develop targeted treatments. This article discusses recent research in modeling adipose tissue fibrosis using in vivo and in vitro (2D and 3D) methods with considerations for biomaterial selections. Additionally, this article outlines the importance of adipose tissue in treating other fibrotic diseases and methods used to detect and characterize adipose tissue fibrosis.

Prospective and randomized comparative study of calcium hydroxylapatite vs calcium hydroxylapatite plus HIFU in treatment of moderate-to-severe acne scars

BACKGROUND

Acne scars are the most common sequelae of the severe inflammatory process of acne, and its managing is a challenge. Objective of this study was to assess safety and effectiveness of calcium hydroxylapatite monotherapy and its association with high-intensity microfocused ultrasound for treating moderate-to-severe atrophic acne scars.

METHODS

Women with moderate-to-severe atrophic scars of the face were enrolled on the study. Assessments were made by digital macrophotographs, Vectra H2, and Antera 3D.

RESULTS

From October to December 2019, twenty women which fitted the inclusion criteria signed a consent form and received 3.0 mL of calcium hydroxylapatite and after 4 weeks, 400 lines of HIFU. No major side effects were reported during the study, and all patients completed the follow-up after 6 months. At 1 month, patients treated with calcium hydroxylapatite (group 1) improved wrinkles and skin texture compared to placebo (group 2). At 3 and 6 months, all patients improved acne scars.

CONCLUSION

Our study showed that that both calcium hydroxylapatite and HIFU in monotherapy were safe and effective treatments for atrophic scar acne. Calcium hydroxylapatite was clinically effective when compared with placebo, though the combination of calcium hydroxylapatite and HIFU did not enhance the clinical efficacy compared to monotherapy.

Fractional carbon dioxide laser combined with intradermal injection of autologous platelet-rich plasma versus noncross-linked hyaluronic acid in the treatment of atrophic postacne scars: A split face study

BACKGROUND

Atrophic acne scarring is a common cosmetic problem that may affect 95% of patients with acne.

AIMS

The objective is to evaluate the efficacy of the fractional CO₂ laser combined with intradermal injection of PRP versus intradermal injection of noncross-linked hyaluronic acid in the treatment of different types of atrophic postacne scars.

METHODS

The study included 30 patients with postacne scars. All the patients received 3 treatments of fractional CO₂ laser combined with intradermal injection of PRP at one side of the face compared with intradermal injection of noncross-linked hyaluronic acid at the other side of the face. Efficacy of the treatment was assessed by the physician's clinical assessment using Goodman and Baron's qualitative and quantitative grading systems and histopathological evaluation from six participants.

RESULTS

The study included 30 patients ages ranging from 25 to 44 years old. There was a statistically significant reduction in the severity of acne scars on both sides after treatment using qualitative and quantitative Goodman and Baron. Histopathological evaluation showed an increase in the collagen and elastic fiber content in both modalities with a more favorable outcome in the PRP-treated side.

CONCLUSION

Both treatment modalities resulted in a significant clinical and histopathological improvement in atrophic postacne scar with insignificant difference between them.