A comparative study of proliferation and hepatic differentiation of human adipose-derived stem cells

Fillers impacting follicles: the emerging complication of filler-induced alopecia

Filler-induced alopecia is a transient alopecia characterized by localized hair loss and often attributed to vascular compromise following dermal filler injections in facial regions. Although an uncommon phenomenon, the rising incidence of filler-induced alopecia underscores the importance of understanding and managing this condition. We performed an extensive PubMed review of articles reporting filler-induced alopecia and summarizing the implicated filler types, injection areas, hair loss patterns, symptom onset, course progression, treatments, and prognosis. Hyaluronic acid injections were the most implicated in filler-induced alopecia cases, with calcium hydroxylapatite and autologous fat less frequently associated. No cases involved other dermal filler types. Although recovery times varied depending on the treatment, hyaluronidase (HAase) injections rapidly restored near-normal hair density within 3-4 months. Minoxidil and platelet-rich plasma play a more minor role in restoring hair growth but may be used as adjuncts with HAase to facilitate hair growth. Finally, alternative interventions like intralesional triamcinolone, warm compresses, and nitroglycerin warrant exploration, given limited robust clinical data. Our study promotes awareness of filler-induced alopecia's rising incidence and offers practical insights and evidence-based recommendations for effective management. By equipping dermatologists with this knowledge, our aim is to improve patient outcomes and reduce adverse events in filler-based procedures.

Rhinoplasty with Fillers and Fat Grafting

Nonsurgical rhinoplasty is one choice for cases in which open surgery may be harmful, the deformity is not indicated to correct with open surgery, or in patients who have phobia of general anesthesia or any type of surgery. Autologous fat injection or fillers are most common materials currently available in the market. In this article, we explain the indications, contraindications, methods, and complications of this treatment.

Laser-Induced Differentiation of Human Adipose-Derived Stem Cells to Temporomandibular Joint Disc Cells

BACKGROUND AND OBJECTIVES

Temporomandibular disorder (TMD) is an incapacitating disease with temporomandibular joint (TMJ) disc degenerative changes in patients. Despite several research attempts to find a definitive treatment, there is no evidence of a permanent solution. The objective of the current study was to observe the role of 660 nm diode laser in the differentiation of human adipose-derived stem cells (ADSCs) to fibroblasts and chondrocytes.

STUDY DESIGN/MATERIALS AND METHODS

After irradiation, the morphology, viability, and adenosine triphosphate (ATP) proliferation of the ADSCs were analyzed at different time intervals. The differentiation of ADSCs toward fibroblastic and chondrogenic phenotypes was supported using flow cytometry and immunofluorescence at 1- and 2-week post-irradiation.

RESULTS

More than 90% of viable cells were observed in all experimental groups, with an increase in ATP proliferation. Flow cytometry analyses and immunofluorescence demonstrated the presence of chondrogenic and fibroblastic cell surface markers at 1- and 2-week post-irradiation.

CONCLUSION

This study has demonstrated methods to induce the differentiation of ADSCs toward fibroblastic and chondrogenic phenotypes with a 660 nm diode laser. The study also proposes a future alternative method of treatment for patients with degenerative TMJ disc disorders and presents a positive prospect in the application of photobiomodulation and ADSCs in the treatment of degenerative TMJ disc. Lasers Surg. Med. © 2020 Wiley Periodicals LLC.

Identification of hepatic progenitor cells in the canine fetal liver

The liver plays essential roles in human and animal organisms, such as the storage, release, metabolism, and elimination of various endogenous or exogenous substances. Although its vital importance, few treatments are yet available when a hepatic failure occurs, and hence, the use of stem cells has arisen as a possible solution for both human and veterinary medicines. Previous studies have shown the existence of hepatic progenitor cells in human fetuses that were positive for EpCAM and NCAM. There is limited evidence, however, further identification and characterization of these cells in other species. Considering the similarity between dogs and humans regarding physiology, and also the increasing importance of developing new treatments for both veterinary and translational medicine, this study attempted to identify hepatic progenitor cells in canine fetal liver. For that, livers from canine fetuses were collected, cells were isolated by enzymatic digestion and cultured. Cells were characterized regarding morphology and expression of EpCAM, NCAM, Nestin, and Thy-1/CD90 markers. Our results suggest that it is possible to identify hepatic progenitor cells in the canine fetal liver; however, for therapeutic use, further techniques for cellular isolation and culture are necessary to obtain enriched populations of hepatic progenitors from the canine fetal liver.

Autologous fat transplantation for secondary breast reconstruction: our experience

BACKGROUND

Autologous fat transplantation is used after breast reconstruction to improve the breast profile. There are a variety of different methods used for fat harvesting, preparation, and reinjection. This study describes the specific techniques we used in this series of autologous fat transplantations in breast reconstruction patients and reports their outcomes compared with other studies in the literature.

PATIENTS AND METHODS

At the University Hospital of Parma between May 2012 and December 2016, we performed 53 autologous fat transplantations for secondary breast reconstruction patients with an average age of 49 years (range: 34-65 y). A tumescent fluid (NaCl, epinephrine, and a local anaesthetic) was injected, and the lipoaspirate was harvested using a closed aspiration-injection system connected to a 50 ml syringe, a 4 mm infiltration cannula, and a -650 mmHg vacuum. The average amount of lipoaspirate obtained was 100 ml (range: 50-200 ml). Centrifugation of the lipoaspirate (3000 rpm for 3 min) was performed to isolate the adipose tissue (average amount obtained, 80 ml; range: 30-180 ml). Under local anaesthesia, the retrograde injection of thin layers of fat graft in multiple tunnels was performed in the subcutaneous and/or subglandular planes.

RESULTS

Average follow-up was six months. Comparable to other studies, our complication rate was 7.4% (n = 4/53) and included cyst formation at the injection site (n = 1/53) and hematoma at the donor site (n = 3/53). Repeat fat grafting was performed in 28.3% of patients (n = 15/53) due to fat graft resorption.

CONCLUSIONS

Autologous fat transplantation is a useful procedure for correcting irregularities in the breast contour in secondary breast reconstruction.

From liposuction to adipose-derived stem cells: indications and technique

Background and aim of the work:

Adipose tissue is an organ of energy storage, an endocrine organ, a soft tissue filler and a cosmetically unnecessary tissue discarded by liposuction. Liposuction was designed to correct unaesthetic deposits of subcutaneous fat; it produces satisfactory silhouette contouring when performed by appropriately trained operators using properly selected technologies. However, from lipoaspirate it is possible to obtain autologous fat graft and adipose-derived stem cells (ASCs) for reconstructive surgery and regenerative medicine. Autologous fat transplantation uses include the correction of body contour, malformations and post-surgical outcomes. The regenerative properties of ASCs allow treating damaged tissues such as wounds, burns, scars and radiodermatitis. The aim of this study was to perform a literature review highlighting the crucial role of adipose tissue in plastic and reconstructive surgery, from liposuction to lipofilling and ASCs, exposing the indications, procedures and complications of these surgical techniques.

Methods:

Literature review of publications concerning liposuction, lipofilling and adipose-derived stem cells (ASCS).

Results:

The introduction of liposuction allowed the use of adipose tissue for many clinical uses. The adipose tissue filling properties have been highlighted by the advent of lipofilling. The regenerative properties evidence of autologous fat transplantation encouraged the research on the clinical use of ASCs.

Conclusions:

Adipose tissue is not only the main energy storage of our body but also an important source of stem cells that can be used in various fields of regenerative medicine and tissue engineering with encouraging results for the future. (www.actabiomedica.it)

Unfiltered Nanofat Injections Rejuvenate Postburn Scars of Face

The aim of this study was to compare the quality of postburn facial scars before and after injection of unfiltered nanofat. The study was performed in the Plastic Surgery Department of Mayo Hospital, Lahore, Pakistan, from January 2015 to December 2016. Forty-eight patients with postburn facial scars were included; age range was 4 to 32 years with Fitzpatrick skin types between 3 and 4. Patients with hypertrophic scars, contractures, or keloids were excluded. Scars were assessed by a senior plastic surgeon and the patient on the POSAS (Patient Observer Scar Assessment Scale). Fat was harvested from the abdomen and/or thighs with a 3-mm multiport liposuction cannula (containing several sharp side holes of 1 mm) using Coleman technique. The harvested fat was emulsified and transferred into 1-mL Luer-Lock syringes for injection into the subdermal or intradermal plane. Final follow-up was scheduled at 6 months, and scar was rated by the patient and the same surgeon on the POSAS. Preoperative and postoperative scar scores were compared, and P values were calculated. Results indicated that after nanofat grafting, there was a statistically significant improvement in scar quality. The most significant improvements on the observer scale were seen in pigmentation and pliability (P < 0.0001). Thickness and relief were the least improved variables (P = of 0.785 and 0.99, respectively). ImageJ scanning also showed pigmentation change (P = 0.076). A statistically significant improvement was seen in all parameters of the patient section of the POSAS (P < 0.0001). In conclusion, unfiltered nanofat grafting seems to be a promising and effective therapeutic approach in postburn facial scars, showing significant improvement in scar quality. The trial was registered on www.clinicaltrials.gov with following ID NCT03352297.

Two-Stage Tissue-Expander Breast Reconstruction: A Focus on the Surgical Technique

OBJECTIVE

Breast cancer, the most common malignancy in women, comprises 18% of all female cancers. Mastectomy is an essential intervention to save lives, but it can destroy one's body image, causing both physical and psychological trauma. Reconstruction is an important step in restoring patient quality of life after the mutilating treatment.

MATERIAL AND METHODS

Tissue expanders and implants are now commonly used in breast reconstruction. Autologous reconstruction allows a better aesthetic result; however, many patients prefer implant reconstruction due to the shorter operation time and lack of donor site morbidity. Moreover, this reconstruction strategy is safe and can be performed in patients with multiple health problems. Tissue-expander reconstruction is conventionally performed as a two-stage procedure starting immediately after mammary gland removal.

RESULTS

Mastectomy is a destructive but essential intervention for women with breast cancer. Tissue expansion breast reconstruction is a safe, reliable, and efficacious procedure with considerable psychological benefits since it provides a healthy body image.

CONCLUSION

This article focuses on this surgical technique and how to achieve the best reconstruction possible.

The science behind autologous fat grafting

INTRODUCTION

Adipose grafting has undergone significant changes over time. Many different techniques have been followed by trying to improve the quality of the lipoaspirate and the survival of the fat graft after implantation.

MATERIAL AND METHODS

The purpose of this review is to analyse the historical evolution of the surgical harvesting and implant technique, describing the changes that have brought significant improvements, revolutionizing the aesthetic and functional results obtainable.

RESULTS

A standard fat grafting technique is commonly performed in three stages: harvesting of adipose tissue from a suitable donor site; processing of the lipoaspirate to eliminate cellular debris, acellular oil and excess of infiltrated solution, reinjection of the purified adipose tissue. The most widely used surgical technique was described by Coleman. He modified and corrected the methods and results of his predecessors and proposed an atraumatic protocol for the treatment of adipose tissue.He reported that the key to successful fat grafting lies in the technique. In addition, he noticed that adipose tissue was not only a good filler, but improved the quality of the skin. In fact, fat grafts demonstrated to have not only dermal filler properties but also regenerative potential owing to the presence of stem cells in fat tissue.

CONCLUSION

Adipose tissue, actually, is the closest to the ideal filler because it is readily available; easily obtainable, with low donor-site morbidity; repeatable; inexpensive; versatile; and biocompatible. There is an abundance of literature supporting the efficacy of fat grafting in both aesthetic and reconstructive cases. Recent studies have shown the utility of adipose-derived stem cells in the improvement of wound healing, describing their ability to regenerate soft tissues and their remodelling capacity provided by their unique cytokine and growth factor profiles.Despite ongoing concerns about survival and longevity of fat grafts after implantation and unpredictability of long-term outcome, fat has been successfully used as a filler in many differ clinic situation.

A journey through liposuction and liposculture: Review

INTRODUCTION

Nowadays, liposuction is the most frequently performed aesthetic surgery procedure in Western Countries. This technique has had rapid development since the 1970s, when it was experimented for the first time by A. and G. Fischer. It is currently widely used in clinical practice for many different situations in aesthetic, reconstructive and functional fields.

MATERIALS AND METHODS

This review aims to describe the historical evolution of liposuction by analyzing the transformation of the method in function of the introduction of innovative ideas or instruments. We have also focused on reporting the major clinical applications of this surgical technique, applicable to almost the entire body surface. We finally analyzed the complications, both major and minor, associated with this surgical technique.

RESULTS

Liposuction is mainly used to correct deep and superficial fat accumulations and remodel the body contour. It has become an essential complementary technique to enhance the aesthetic result of many other aesthetic procedures such as reduction mammoplasty, abdominoplasty, brachioplasty, thigh lift and post bariatric body contouring. However, it can be largely used for the treatment of innumerable pathologies in reconstructive surgery such as lipomas, lipedema, lipodystrophies, pneudogynecomastia and gynecomastia, macromastia e gigantomastia, lymphedema and many others. The complication rate is very low, especially when compared with conventional excisional surgery and the major, complications are generally associated with improper performance of the technique and poor patient management before and after surgery.

CONCLUSION

Liposuction is a safe, simple and effective method of body contouring. It has enormous potential for its application in ablative and reconstructive surgery, far from the most common aesthetic processes with a very low complication rate.

Clinical use of adipose-derived stem cells: European legislative issues

Objective

With this study we analyse the current European legislation in order to provide guidance for regenerative medicine professionals on correct Adipose-derived Stem Cells (ASCs) isolation and use protocols for clinical applications.

Materials and Methods

The European Medicines Agency (EMA) considers that ASCs does not fall within the definition of an advanced therapy medicinal product if the cells have not been subjected to a substantial manipulation, and the mode of action of the cells (contribute to and enhance tissue renewal and turnover of the subcutaneous tissue) is considered to be homologous to the donor fat tissue.

Results

Collagenase digestion, as well as cell culturing, is considered to be a substantial manipulation. Only transplantation of a non-manipulated tissue to another location in the same anatomical or histological environment is considered to be homologous.

Conclusions

According to these considerations, ASCs should be not-cultured, isolated mechanically and used only in the subcutaneous tissue.

Off-label use of adipose-derived stem cells

Background

Adipose-derived stem cells (ASCs) have a broad range of clinical applications. The ease of cell harvest and high yield with minimal donor-site morbidity makes adipose tissue an ideal source of stem cells. Further, the multi-lineage potential of these cells present significant opportunities within the field of tissue engineering, with studies successfully demonstrating their ability to produce a range of tissue types.

Materials and methods

Literature review of publications on the use of ASCs, in the context of current European and US regulations.

Results

According to European and US regulations, many clinical trials reported in literature to date could be considered off-label.

Conclusion

In Europe, clinical trials involving cultured ASCs and/or the use of collagenase, which causes changes in the structural and functional properties of stem cells, and/or ASCs application in non-homologous tissue, should be considered off-label. ASCs should be non-cultured, isolated mechanically, and used only in the subcutaneous tissue.

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Adipose-derived stem cells hold enormous potential in different fields of regenerative medicine and stem cell therapy.

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According to European and US regulations, many clinical trials reported in literature could be considered off-label.

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In Europe, ASCs should be non-cultured, isolated mechanically, and used only in the subcutaneous tissue.

One-Stage Immediate Breast Reconstruction: A Concise Review

BACKGROUND

One-stage direct-to-implant immediate breast reconstruction (IBR) is performed simultaneously with breast cancer resection. We explored indications, techniques, and outcomes of IBR to determine its feasibility, safety, and effectiveness.

MATERIAL AND METHODS

We reviewed the available literature on one-stage direct-to-implant IBR, with or without acellular dermal matrix (ADM), synthetic mesh, or autologous fat grafting. We analyzed the indications, preoperative work-up, surgical technique, postoperative care, outcomes, and complications.

RESULTS

IBR is indicated for small-to-medium nonptotic breasts and contraindicated in patients who require or have undergone radiotherapy, due to unacceptably high complications rates. Only patients with thick, well-vascularized mastectomy flaps are IBR candidates. Expandable implants should be used for ptotic breasts, while anatomical shaped implants should be used to reconstruct small-to-medium nonptotic breasts. ADMs can be used to cover the implant during IBR and avoid muscle elevation, thereby minimizing postoperative pain. Flap necrosis, reoperation, and implant loss are more common with IBR than conventional two-staged reconstruction, but IBR has advantages such as lack of secondary surgery, faster recovery, and better quality of life.

CONCLUSIONS

IBR has good outcomes and patient-satisfaction rates. With ADM use, a shift from conventional reconstruction to IBR has occurred. Drawbacks of IBR can be overcome by careful patient selection.

Breast reconstruction with anatomical implants: A review of indications and techniques based on current literature

One important modality of breast cancer therapy is surgical treatment, which has become increasingly less mutilating over the last century. Breast reconstruction has become an integrated part of breast cancer treatment due to long-term psychosexual health factors and its importance for breast cancer survivors. Both autogenous tissue-based and implant-based reconstruction provides satisfactory reconstructive options due to better surgeon awareness of "the ideal breast size", although each has its own advantages and disadvantages. An overview of the current options in breast reconstruction is presented in this article.

Tissue expansion for breast reconstruction: Methods and techniques

OBJECTIVE

In this work, the authors review recent data on the different methods and techniques of TE/implant-based reconstruction to determine the complication profiles and the advantages and disadvantages of the different techniques. This information will be valuable for surgeons performing breast reconstructions.

MATERIALS AND METHODS

A thorough literature review was conducted by the authors concerning the current strategy of tissue expander (TE)/implant-based breast reconstruction following breast cancer surgery.

RESULTS

Loss of the breast can strongly affect a woman's personal and social life while breast reconstruction reduces the sense of mutilation felt by women after a mastectomy, and provides psychosocial as well as aesthetic benefits. TE/implant-based reconstruction is the most common breast reconstructive strategy, constituting almost 65% of all breast reconstructions in the US. Although numerous studies have been published on various aspects of alloplastic breast reconstructions, most studies are single-center observations. No evidence-based guidelines are available as yet. Conventional TE/implant-based reconstruction can be performed as a two-stage procedure either in the immediate or delayed setting. Moreover, the adjunctive use of acellular dermal matrix further broadened the alloplastic breast reconstruction indication and also enhanced aesthetic outcomes.

CONCLUSIONS

TE/implant-based reconstruction has proved to be a safe, cost-effective, and reliable technique that can be performed in women with various comorbidities. Short operative time, fast recovery, and absence of donor site morbidity are other advantages over autologous breast reconstruction.

Procedure, applications, and outcomes of autologous fat grafting

OBJECTIVE

To systematically review the procedure, applications, and outcomes of autologous fat grafting, a promising technique with various clinical applications.

PATIENTS AND METHODS

Literature review of publications concerning autologous fat grafting.

RESULTS

Since its introduction, lipofilling has become increasingly popular; however, its results are variable and unpredictable. Several modifications have been made to the procedures of fat harvesting, processing, and injecting. Surgical excision and low negative-pressure aspiration with large-bore cannulas minimize adipocyte damage during fat harvesting. The "wet" method of fat harvesting involves fluid injection at the donor site and facilitates lipoaspiration while minimizing pain and ecchymosis. For fat processing, centrifugation at a low speed is preferable to high-speed centrifugation, gravity separation or filtration. Fat injection at the recipient site should be performed using small-gauge cannulas in a fanning out pattern over multiple sessions, rather than a single session. Fat grafts exhibit not only dermal filler properties but also regenerative potential owing to the presence of stem cells in fat tissue. Thus, the clinical applications of autologous fat grafting include correction of secondary contour defects after breast reconstruction, release of painful scar contractures, and treatment of burn scars and radiodermatitis. Lipofilling is also used in aesthetic surgery, such as facial and hand rejuvenation, augmentation rhinoplasty, and breast and gluteal augmentation. The complications of lipofilling are minimal and include bruising, swelling, pain, infection, necrosis, and calcification.

CONCLUSIONS

Lipofilling is a low-risk procedure that can be used to correct soft-tissue defects in the face, trunk, and extremities, with minimal discomfort for patients.

Adipose-derived stem cells: Comparison between two methods of isolation for clinical applications

Background

Adipose-derived stem cells are recognized as being an effective mesenchymal stem cell population with enormous potential in different fields of regenerative medicine and stem cell therapy. Although there is unanimous agreement on the harvesting procedure for adipose tissue, there are various protocols for adipose-derived stem cell isolation. The aim of this study was compare two methods of adipose-derived stem cells (ASCs) isolation, one based on a mechanical + enzymatic (ME) procedure and the other one exclusively mechanical (MC), in order to determine which one was superior to the other in accordance with current European and US legislation.

Methods

We reported step by step the two different methods ASCs isolation by comparing them. The ME procedure included the use of a centrifuge, an incubator and collagenase digestion solution (Collagenase NB 6 GMP Grade 17458; Serva GmbH, Heidelberg, Germany). The MC procedure was performed by vibrating shaker and centrifuge, both placed in a laminar airflow bench.

Results

With the ME procedure, a mean of 9.06 × 10⁵ ASCs (range, 8.4 to 9.72 × 10⁵; SD ± 6.6 × 10⁵) was collected, corresponding to 25.9% of the total number of harvested cells. With the MC procedure, a mean of 5 × 10⁵ ASCs (range: 4.0 to 6.0 × 10⁵; SD, ±1 × 10⁵) was collected, corresponding to 5% of the total number of harvested cells.

Conclusion

Based on data collected, from the same amount of lipoaspirate the ME procedure allowed to isolate a greater number of ASCs (25,9%) compared to the MC one (5%).

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Adipose-derived stem cells (ASCs) are effective mesenchymal stem cell population with enormous potential.

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In this study we compared two methods of adipose-derived stem cells (ASCs) isolation.

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Gathered data showed a greater amount of isolated ASCs by the ME procedure as compared to the MC one.

The biological and clinical basis for the use of adipose-derived stem cells in the field of wound healing

Worldwide, hard-to-heal lower limb wounds are estimated to affect 1.5–3% of the adult population with a treatment-related annual cost of $10 billion. Thus, chronic skin ulcers of the lower limb are a matter of economic and public concern. Over the years, multiple medical and surgical approaches have been proposed but they are still inadequate, and no effective therapy yet exists. Regenerative medicine and stem cell-based therapies hold great promise for wound healing. Recently, many plastic surgeons have studied the potential clinical application of adipose-derived stem cells (ASCs), which are a readily available adult stem cell population that can undergo multilineage differentiation and secrete growth factors that can enhance wound-healing processes by promoting angiogenesis, and hence increase local blood supply. ASCs have been widely studied in vitro and in vivo in animal models. However, there are few randomized clinical trials on humans, and these are still ongoing or recruiting patients. Moreover, there is no consensus on a common isolation protocol that is clinically feasible and which would ensure reproducible results. The authors aim to provide readers with an overview of the biological properties of ASCs as well as their clinical application, to help better understanding of present and future strategies for the treatment of hard-to-heal wounds by means of stem cell-based therapies.

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Worldwide, hard-to-heal wounds are a matter of economic and public concern.

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The emerging fields of regenerative medicine and stem cell-based therapies hold great promise for wound healing.

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ASCs can potentially give the support necessary for recovery of hard-to-heal wounds.

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ASCs can be easily harvested from adipose tissue by means of standard wet liposuction technique.

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ASCs have been widely studied in vitro and in vivo to demonstrate their potential and safety.

Fat grafting for chronic heel pain following surgery for adult flatfoot deformity: Pilot study

INTRODUCTION

Autologous fat grafting is now a highly popular technique in plastic and reconstructive surgery, with broad applicability for various surgical procedures. Fat grafting can impart contours and augmentation, nourish tissue, modulate scar tissue, and produce regeneration at the recipient site. In this pilot study, the authors suggest that fat grafting may be useful therapeutic adjunct for cases of chronic heel pain following surgery for adult flatfoot deformity.

MATERIALS AND METHODS

Eight patients with chronic heel pain following surgery for adult flatfoot deformity underwent autologous subcutaneous heel fat grafting and recorded their levels of pain relief for 6 months postoperatively.

RESULTS

The authors recorded a statistically significant difference (p<0.001) between pain scale values recorded before (t0) and six months postoperatively (t6). From t0 to t6, mean pain scale values changed from 8.125 to 2.413.

CONCLUSIONS

Volumetric enhancement of the subcutaneous heel fat pad significantly ameliorated weight-bearing pain in these patients.

Mesenchymal Stem Cells Transplantation following Partial Hepatectomy: A New Concept to Promote Liver Regeneration-Systematic Review of the Literature Focused on Experimental Studies in Rodent Models

Mesenchymal stem cells (MSCs) are an attractive source for regenerative medicine because they are easily accessible through minimally invasive methods and have the potential to enhance liver regeneration (LG) and improve liver function, following partial hepatectomy (PH) and acute or chronic liver injury. A systematic review of the literature was conducted for articles published up to September 1st, 2016, using the MEDLINE database. The keywords that were used in various combinations were as follows: “Mesenchymal stem cells”, “transplantation”, “stem cells”, “adipose tissue derived stem cells”, “bone marrow-derived stem cells”, “partial hepatectomy”, “acute liver failure”, “chronic liver failure”, “liver fibrosis”, “liver cirrhosis”, “rats”, “mice”, and “liver regeneration”. All introduced keywords were searched for separately in MeSH Database to control relevance and terminological accuracy and validity. A total of 41 articles were identified for potential inclusion and reviewed in detail. After a strict selection process, a total of 28 articles were excluded, leaving 13 articles to form the basis of this systematic review. MSCs transplantation promoted LG and improved liver function. Furthermore, MSCs had the ability to differentiate in hepatocyte-like cells, increase survival, and protect hepatocytes by paracrine mechanisms. MSCs transplantation may provide beneficial effects in the process of LG after PH and acute or chronic liver injury. They may represent a new therapeutic option to treat posthepatectomy acute liver failure.

Plasma Oxidative Stress in Patients With Chronic Vascular Cutaneous Ulcers

Oxidative stress is hypothesized to be one of the main causes of the pathophysiologic alterations observed during impaired healing of wounds. In the present study, we aimed to measure systemic levels of free radicals in blood and anti-oxidant (AO) activity in the plasma of patients with chronic ulcers (venous stasis ulcers and arterial insufficiency ulcers) of lower extremities (CULEs). Oxidants and AO activity were measured in eighty-five consecutive patients with CVSUs of the lower extremities as they arrived randomly for routine visits to our ambulatory clinic. Values of oxidant and AO status in patients with CULEs were significantly different from normal. No significant differences in oxidant and AO values were found between patients with arterial ulcers or those with venous ulcers. A significant difference was found in AO values of diabetic patients with chronic venous ulcers compared with non-diabetic patients with chronic venous ulcers. No significant differences were observed when evaluating oxidant/AO values and smoking habits. Precise reasons why the association of diabetes and venous (but not arterial) ulcers was correlated with defective AO status in plasma are not known. Other data were also intriguing: diminished AO activity was observed in female patients, no significant differences in oxidant and values were found between patients with arterial ulcers or those with venous ulcers, no significant correlation was found between age and oxidant, as well as no significant differences were observed when evaluating oxidant/AO values and smoking habits.

Autologous fat transplantation for breast reconstruction: A literature review

INTRODUCTION

The use of autologous fat transplantation to correct volume and contour defects, scars, and asymmetry after breast cancer surgery has increased over the past 20 years. Many developments and refinements in this technique have taken place in recent years, and several studies of the safety of lipofilling in the breast have been published.

PRESENTATION OF CASE

We performed a literature review of this technique, highlighting the crucial role of lipofilling in breast cancer reconstruction.

DISCUSSION

The efficacy of the fat graft transplantation depends on the experience and the technique used by the surgeon. The ASCs (adipose-derived stem cells) contained in the fat graft has proven to be crucial for breast reconstruction by mean the regeneration of tissue, through the chemotactic, paracrine, and immunomodulatory activities and their in situ differentiation.

CONCLUSION

The role of lipofilling for breast reconstruction could be more significant with the application of the findings of experimental research on tissue engineering and ASCs.

Role of Stem Cells Transplantation in Tissue Regeneration After Acute or Chronic Acetaminophen Induced Liver Injury

PURPOSE

Acetaminophen-induced liver injury (APAP) is recognized as a frequent etiologic factor responsible for hepatic damage in the developed world. Management remains still elusive as treatment options are limited and their results are inconclusive. Consequently new strategies are explored at the experimental level. Mesenchymal stem cells (MSCs) present a promising modality as they can promote liver regeneration (LG) and compensate acute liver injury (ALI).

MATERIALS AND METHODS

Our research was focused on articles related to drug-induced liver injury, mechanisms of liver regeneration (LG) after Acute Liver Injury (ALI) and recent experimental protocols of Mesenchymal Stem Cells (MSCs) transplantation after chemical insult. All these studies are cited on Pubmed and MedLine.

RESULTS

This review has three distinct sections. First recent developments in ALI pathogenesis are presented. The second section covers cellular pathways and histological findings relevant to liver regeneration. The final chapter analyzes MSCs transplantation protocols after ALI and interrelation between liver regeneration and hepatic differentiation of MSCs.

CONCLUSION

Adipose tissue stem cells (ADSCs) and (MSCs) transplantation represents a promising modality in severe ALI management although many aspects remain to be clarified.

Cell-based therapies of liver diseases: age-related challenges

The scope of this review is to revise recent advances of the cell-based therapies of liver diseases with an emphasis on cell donor's and patient's age. Regenerative medicine with cell-based technologies as its integral part is focused on the structural and functional restoration of tissues impaired by sickness or aging. Unlike drug-based medicine directed primarily at alleviation of symptoms, regenerative medicine offers a more holistic approach to disease and senescence management aimed to achieve restoration of homeostasis. Hepatocyte transplantation and organ engineering are very probable forthcoming options of liver disease treatment in people of different ages and vigorous research and technological innovations in this area are in progress. Accordingly, availability of sufficient amounts of functional human hepatocytes is crucial. Direct isolation of autologous hepatocytes from liver biopsy is problematic due to related discomfort and difficulties with further expansion of cells, particularly those derived from aging people. Allogeneic primary human hepatocytes meeting quality standards are also in short supply. Alternatively, autologous hepatocytes can be produced by reprogramming of differentiated cells through the stage of induced pluripotent stem cells. In addition, fibroblasts and mesenchymal stromal cells can be directly induced to undergo advanced stage hepatogenic differentiation. Reprogramming of cells derived from elderly people is accompanied by the reversal of age-associated changes at the cellular level manifesting itself by telomere elongation and the U-turn of DNA methylation. Cell reprogramming can provide high quality rejuvenated hepatocytes for cell therapy and liver tissue engineering. Further technological advancements and establishment of national and global registries of induced pluripotent stem cell lines homozygous for HLA haplotypes can allow industry-style production of livers for immunosuppression-free transplantation.

Cell-microsphere constructs formed with human adipose-derived stem cells and gelatin microspheres promotes stemness, differentiation, and controlled pro-angiogenic potential

Translation of stem cell therapies to clinical stage requires viable delivery vehicles that can control stem cell behavior. In this study, the suitability of gelatin microspheres (GMs) as such a tissue engineering platform for human adipose derived stem cells (ADSCs) is investigated. ADSCs on GMs, show a significant upregulation of well known pluripotent marker genes, together with the ability to differentiate into multiple cell lineages of adipocytes, osteocytes, and hepatocytes. In addition, the pro-angiogenic ability of ADSC-GMs is also enhanced compared to ADSCs on 2D culture plates. These results suggest that GMs can be a suitable culture platform for ADSCs with enhanced therapeutic potential.

Human hepatic progenitor cells express hematopoietic cell markers CD45 and CD109

OBJECTIVE

To clarify the precise characteristics of human hepatic progenitor cells (HPCs) for future cytotherapy in liver diseases.

METHODS

Hepatic progenitor-like cells were isolated and cultured from the livers of patients who had undergone partial hepatectomy for various pathologies but displayed no sign of hepatic dysfunction. These cells were characterized by transcriptomic profiling, quantitative real-time PCR and immunocyto/histochemistry.

RESULTS

Cultured HPCs contained polygonal, high nucleus/cytoplasm ratio and exhibited a global gene expression profile similar (67.8%) to that of primary hepatocytes. Among the genes with more than 20-fold higher expression in HPCs were a progenitor marker (CD90), a pentraxin-related gene (PTX3), collagen proteins (COL5A2, COL1A1 and COL4A2), cytokines (EGF and PDGFD), metabolic enzymes (CYBRD1, BCAT1, TIMP2 and PAM), a secreted protein (SPARC) and an endothelial protein C receptor (PROCR). Moreover, eight markers (ALB, AFP, CK8, CK18, CK19, CD90, CD117 and Oval-6) previously described as HPC markers were validated by qRT-PCR and/or immunocyto/histochemistry. Interestingly, human HPCs were also positive for the hematopoietic cell markers CD45 and CD109. Finally, we characterized the localization of HPCs in the canals of Hering and periportal areas with six previously described markers (Oval-6, CK8, CK18, CK19, CD90 and CD117) and two potential markers (CD45 and CD109).

CONCLUSION

The human HPCs are highly similar to primary hepatocytes in their transcriptional profiles. The CD45 and CD109 markers could potentially be utilized to identify and isolate HPCs for further cytotherapy of liver diseases.

Hepatogenic differentiation of human mesenchymal stem cells from peritoneal adipose tissue

Backgrounds/Aims

It has been reported that functional hepatogenic differentiation has the possibility to occur in subcutaneous adipose tissue-derived stem cells. However, no studies have investigated whether the adipose tissue-driven stem cells present in various body parts differ according to hepatogenic differentiations. In this study, stem cells were separated from body visceral fat and abdominal subcutaneous adipose tissue, and cultured, and then hepatogenic differentiation was induced. We aim to investigate the possibilities and aspects of hepatogenic differentiations within the two types of fat cells.

Methods

Omental fat tissues were obtained as visceral fat and abdominal subcutaneous adipose tissues were obtained from patients who had suction-assisted lipectomy. Stem cells were separated from the obtained fat tissues, and then, hepatogenic differentiation was carried out by utilizing 2-step differentiation protocols.

Results

After the differentiation, two types of cultured cells that showed the similar neuron-like shapes were changed to cuboidal shapes and included several binucleated cells which could be characteristics of mature hepatocytes. We confirmed that hepatocyte specific genes and proteins such as albumin and CYP3A4 were being expressed. By utilizing the ELISA test, we were able to observe that the albumin was secreted into the culture fluids in both cells. After completing the differentiation, we observed the presence of the hepatocyte specific properties by confirming glycogen storage within the cells and the ICG reagent uptake.

Conclusions

We confirmed that hepatogenic differentiation was possible to occur in the omental fat as well as subcutaneous adipose tissue.

In vitro characterization of multipotent mesenchymal stromal cells isolated from palatal subepithelial tissue grafts

The aim of this study was to analyze whether the mesenchymal stromal cells (MSCs) isolated from palatal tissue grafts harvested in order to cover gingival recessions have the basic characteristics of stem cells. The palatal tissue cells were processed using a special culture medium that stimulated the development of only undifferentiated cellular lines. Cells at passage 4 were evaluated by flow cytometry to examine the expression of specific surface markers and were tested for multilineage differentiation capacity. These cells collected at passage 4 were also investigated for the capacity to cluster into embryoid body aggregates. Palatal MSCs displayed positive staining for the mesenchymal markers CD29, CD73, CD105, CD 49e, and CD44, but did not express hematopoietic markers CD34/45. The palatal MSCs successfully differentiated into osteogenic, adipogenic, and chondrogenic lineages. When seeded in special conditions, palatal MSCs propagated into unattached spheres resembling embryoid body aggregates consisting both of differentiated and undifferentiated cells as revealed at the ultrastructural evaluation. It is concluded that the isolated palatal MSCs fulfilled the basic criteria defining the stem cells. This new source of stem cells characterized here for the first time opens new perspectives on possible applications in basic research and in regenerative medicine.

Advances in cell sources of hepatocytes for bioartificial liver

BACKGROUND

Orthotopic liver transplantation (OLT) is the most effective therapy for liver failure. However, OLT is severely limited by the shortage of liver donors. Bioartificial liver (BAL) shows great potential as an alternative therapy for liver failure. In recent years, progress has been made in BAL regarding genetically engineered cell lines, immortalized human hepatocytes, methods for preserving the phenotype of primary human hepatocytes, and other functional hepatocytes derived from stem cells.

DATA SOURCES

A systematic search of PubMed and ISI Web of Science was performed to identify relevant studies in English language literature using the key words such as liver failure, bioartificial liver, hepatocyte, stem cells, differentiation, and immortalization. More than 200 articles related to the cell sources of hepatocyte in BAL were systematically reviewed.

RESULTS

Methods for preserving the phenotype of primary human hepatocytes have been successfully developed. Many genetically engineered cell lines and immortalized human hepatocytes have also been established. Among these cell lines, the incorporation of BAL with GS-HepG2 cells or alginate-encapsulated HepG2 cells could prolong the survival time and improve pathophysiological parameters in an animal model of liver failure. The cBAL111 cells were evaluated using the AMC-BAL bioreactor, which could eliminate ammonia and lidocaine, and produce albumin. Importantly, BAL loading with HepLi-4 cells could significantly improve the blood biochemical parameters, and prolong the survival time in pigs with liver failure. Other functional hepatocytes differentiated from stem cells, such as human liver progenitor cells, have been successfully achieved.

CONCLUSIONS

Aside from genetically modified liver cell lines and immortalized human hepatocytes, other functional hepatocytes derived from stem cells show great potential as cell sources for BAL. BAL with safe and effective liver cells may be achieved for clinical liver failure in the near future.

The influence of spheroid formation of human adipose-derived stem cells on chitosan films on stemness and differentiation capabilities

Adipose-derived stem cells (ASCs) have valuable applications in regenerative medicine, but maintaining the stemness of ASCs during in vitro culture is still a challenging issue. In this study, human ASCs spontaneously formed three-dimensional spheroids on chitosan films. Most ASCs within the spheroid were viable, and the cells produced more extracellular molecules, like laminin and fibronectin. Comparing to monolayer culture, ASC spheroids also exhibited enhanced cell survival in serum deprivation condition. Although cell proliferation was inhibited in spheroids, ASCs readily migrated out and proliferated upon transferring spheroids to another adherent growth surface. Moreover, spheroid-derived ASCs exhibited higher expansion efficiency and colony-forming activity. Importantly, we demonstrated that spheroid formation of human ASCs on chitosan films induced significant upregulation of pluripotency marker genes (Sox-2, Oct-4 and Nanog). By culturing the ASC spheroids in proper induction media, we found that ASC differentiation capabilities were significantly enhanced after spheroid formation, including increased transdifferentiation efficiency into neuron and hepatocyte-like cells. In a nude mice model, we further showed a significantly higher cellular retention ratio of ASC spheroids after intramuscular injection of spheroids and dissociated ASCs. These results suggested that ASCs cultured as spheroids on chitosan films can increase their therapeutic potentials.

Bottom-up signaling from HGF-containing surfaces promotes hepatic differentiation of mesenchymal stem cells

The capacity of stem cells to differentiate into specific cell types makes them very promising in tissue regeneration and repair. However, realizing this promise requires novel methods for guiding lineage-specific differentiation of stem cells. In this study, hepatocyte growth factor (HGF), an important morphogen in liver development, was co-printed with collagen I (Col) to create arrays of protein spots on glass. Human adipose stem cells (ASCs) were cultured on top of the HGF/Col spots for 2weeks. The effects of surface-immobilized HGF on hepatic differentiation of ASCs were analyzed using RT-PCR, ELISA and immunocytochemistry. Stimulation of stem cells with HGF from the bottom-up caused an upregulation in synthesis of α-fetoprotein and albumin, as determined by immunocytochemistry and ELISA. RT-PCR results showed that the mRNA levels for albumin, α-fetoprotein and α1-antitrypsin were 10- to 20-fold higher in stem cells cultured on the HGF/Col arrays compared to stem cells on Col only spots. Our results show that surfaces containing HGF co-printed with ECM proteins may be used to differentiate mesenchymal stem cells such as ASCs into hepatocyte-like cells. These results underscore the utility of growth factor-containing culture surfaces for stem cell differentiation.