Differentiation ability of adipose-derived stem cells separated from adipose tissue by a membrane filtration method

Purification of Colon Carcinoma Cells from Primary Colon Tumor Using a Filtration Method via Porous Polymeric Filters

Cancer stem cells (CSCs) or cancer-initiating cells (CICs) are key factors for tumor generation and metastasis. We investigated a filtration method to enhance CSCs (CICs) from colon carcinoma HT-29 cells and primary colon carcinoma cells derived from patient colon tumors using poly(lactide-co-glycolic acid)/silk screen (PLGA/SK) filters. The colon carcinoma cell solutions were permeated via porous filters to obtain a permeation solution. Then, the cell cultivation media were permeated via the filters to obtain the recovered solution, where the colon carcinoma cells that adhered to the filters were washed off into the recovered solution. Subsequently, the filters were incubated in the culture media to obtain the migrated cells via the filters. Colon carcinoma HT-29 cells with high tumorigenicity, which might be CSCs (CICs), were enhanced in the cells in the recovered solution and in the migrated cells based on the CSC (CIC) marker expression, colony-forming unit assay, and carcinoembryonic antigen (CEA) production. Although primary colon carcinoma cells isolated from colon tumor tissues contained fibroblast-like cells, the primary colon carcinoma cells were purified from fibroblast-like cells by filtration through PLGA/SK filters, indicating that the filtration method is effective in purifying primary colon carcinoma cells.

Enrichment of cancer-initiating cells from colon cancer cells through porous polymeric membranes by a membrane filtration method

Cancer-initiating cells (CICs) or cancer stem cells (CSCs) are primarily responsible for tumor initiation, growth, and metastasis and represent a few percent of the total tumor cell population. We designed a membrane filtration protocol to enrich CICs (CSCs) from the LoVo colon cancer cell line via nylon mesh filter membranes with 11 and 20 μm pore sizes and poly(lactide-co-glycolic acid)/silk screen (PLGA/silk screen) porous membranes (pore sizes of 20-30 μm). The colon cancer cell solution was filtered through the membranes to obtain a permeate solution. Subsequently, the cell culture medium was filtered through the membranes to collect the recovery solution where the cells attached to the membranes were rinsed off into the recovery solution. Then, the membranes were cultivated in the cultivation medium to collect the migrated cells from the membranes. The cells migrated from any membrane had higher expression of the CSC surface markers CD44 and CD133, had higher colony formation levels, and produced more carcinoembryonic antigen (CEA) than the colon cancer cells cultivated on conventional tissue culture plates (control). We established a method to enrich the CICs (CSCs) of colon cancer cells from migrated cells through porous polymeric membranes by the membrane filtration protocol developed in this study.

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.

Culture and differentiation of purified human adipose-derived stem cells by membrane filtration via nylon mesh filters

Human adipose derived stem cells purified by the membrane migration method through filter membranes coated with vitronectin showed high osteogenic differentiation.

Does lipofilling after oncologic breast surgery increase the amount of suspicious imaging and required biopsies?-A systematic meta-analysis

OBJECTIVE

The aim of our systematic meta-analysis was to find out if lipofilling to the breast alters follow-up imaging procedures and leads to an increased number of biopsies because of suspicious findings.

METHODS

We conducted a systematic meta-analysis of the literature including all prospective and retrospective studies focusing on imaging outcomes in patients with a history of breast cancer who have received one or more lipofilling procedures after oncologic surgery to the breast.

RESULTS

Twelve studies met the inclusion criteria, comprising 1711 patients and at least 2261 lipofilling procedures. 564 patients (33%) were followed up only with ultrasound, 735 patients (43%) only received mammography, 273 (16%) had a combination of ultrasound, mammography and MRI, and 37 patients (2.1%) were followed up via ultrasound and mammography. A collective of 102 patients making up a matched-cohort study received ultrasound, mammography, MRI, and PET/CT, while only 51 of them made up the investigation group who had autologous fat grafting (3%). Biopsy rates were 1%-24% with a medium of 6.5% over all groups. Medium follow-up was 18.8 months (range 6-50 months). The rate of local oncologic events among the patients with lipofilling procedures detected during the study periods was 0.7%.

CONCLUSION

Lipofilling to the breast after oncologic operations appears to be a safe procedure with overall low biopsy and local recurrence rate. Suspicious imaging occurs in most cases out of physiologic remodeling and inflammation processes at the operation site and needs to be distinguished from malignant focusses. The amount of required biopsies stands in relation to the used imaging method and the time to follow-up.

Strategic Design and Fabrication of Biomimetic 3D Scaffolds: Unique Architectures of Extracellular Matrices for Enhanced Adipogenesis and Soft Tissue Reconstruction

The higher rate of soft tissue impairment due to lumpectomy or other trauma greatly requires the restoration of the irreversibly lost subcutaneous adipose tissues. The nanofibers fabricated by conventional electrospinning provide only a superficial porous structure due to its sheet like 2D structure and thereby hinder the cell infiltration and differentiation throughout the scaffolds. Thus we developed a novel electrospun 3D membrane using the zwitterionic poly (carboxybetaine-co-methyl methacrylate) co-polymer (CMMA) through electrostatic repulsion based electrospinning for soft tissue engineering. The inherent charges in the CMMA will aid the nanofiber to directly transform into a semiconductor and thereby transfer the immense static electricity from the grounded collector and will impart greater fluffiness to the scaffolds. The results suggest that the fabricated 3D nanofiber (CMMA 3NF) scaffolds possess nanofibers with larger inter connected pores and less dense structure compared to the conventional 2D scaffolds. The CMMA 3NF exhibits significant cues of soft tissue engineering such as enhanced biocompatibility as well as the faster regeneration of cells. Moreover the fabricated 3D scaffolds greatly assist the cells to develop into its stereoscopic topographies with an enhanced adipogenic property.

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.

Purification and differentiation of human adipose-derived stem cells by membrane filtration and membrane migration methods

Human adipose-derived stem cells (hADSCs) are easily isolated from fat tissue without ethical concerns, but differ in purity, pluripotency, differentiation ability, and stem cell marker expression, depending on the isolation method. We isolated hADSCs from a primary fat tissue solution using: (1) conventional culture, (2) a membrane filtration method, (3) a membrane migration method where the primary cell solution was permeated through membranes, adhered hADSCs were cultured, and hADSCs migrated out from the membranes. Expression of mesenchymal stem cell markers and pluripotency genes, and osteogenic differentiation were compared for hADSCs isolated by different methods using nylon mesh filter membranes with pore sizes ranging from 11 to 80 μm. hADSCs isolated by the membrane migration method had the highest MSC surface marker expression and efficient differentiation into osteoblasts. Osteogenic differentiation ability of hADSCs and MSC surface marker expression were correlated, but osteogenic differentiation ability and pluripotent gene expression were not.

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.

Surface-Functionalized Silk Fibroin Films as a Platform To Guide Neuron-like Differentiation of Human Mesenchymal Stem Cells

Surface interactions at the biomaterial-cellular interface determine the proliferation and differentiation of stem cells. Manipulating such interactions through the surface chemistry of scaffolds renders control over directed stem cell differentiation into the cell lineage of interest. This approach is of central importance for stem cell-based tissue engineering and regenerative therapy applications. In the present study, silk fibroin films (SFFs) decorated with integrin-binding laminin peptide motifs (YIGSR and GYIGSR) were prepared and employed for in vitro adult stem cell-based neural tissue engineering applications. Functionalization of SFFs with short peptides showcased the peptide sequence and nature of functionalization-dependent differentiation of bone marrow-derived human mesenchymal stem cells (hMSCs). Intriguingly, covalently functionalized SFFs with GYIGSR hexapeptide (CL2-SFF) supported hMSC proliferation and maintenance in an undifferentiated pluripotent state and directed the differentiation of hMSCs into neuron-like cells in the presence of a biochemical cue, on-demand. The observed morphological changes were further corroborated by the up-regulation of neuronal-specific marker gene expression (MAP2, TUBB3, NEFL), confirmed through semiquantitative reverse-transcription polymerase chain reaction (RT-PCR) analysis. The enhanced proliferation and on-demand directed differentiation of adult stem cells (hMSCs) by the use of an economically viable short recognition peptide (GYIGSR), as opposed to the integrin recognition protein laminin, establishes the potential of SFFs for neural tissue engineering and regenerative therapy applications.

Implications for human adipose-derived stem cells in plastic surgery

Adipose-derived stem cells (ADSCs) are a subset of mesenchymal stem cells (MSCs) that possess many of the same regenerative properties as other MSCs. However, the ubiquitous presence of ADSCs and their ease of access in human tissue have led to a burgeoning field of research. The plastic surgeon is uniquely positioned to harness this technology because of the relative frequency in which they perform procedures such as liposuction and autologous fat grafting. This review examines the current landscape of ADSC isolation and identification, summarizes the current applications of ADSCs in the field of plastic surgery, discusses the risks associated with their use, current barriers to universal clinical translatability, and surveys the latest research which may help to overcome these obstacles.

Stem cells in plastic surgery: a review of current clinical and translational applications

BACKGROUND

Stem cells are a unique cell population characterized by self-renewal and cellular differentiation capabilities. These characteristics, among other traits, make them an attractive option for regenerative treatments of tissues defects and for aesthetic procedures in plastic surgery. As research regarding the isolation, culture and behavior of stem cells has progressed, stem cells, particularly adult stem cells, have shown promising results in both translational and clinical applications.

METHODS

The purpose of this review is to evaluate the applications of stem cells in the plastic surgery literature, with particular focus on the advances and limitations of current stem cell therapies. Different key areas amenable to stem cell therapy are addressed in the literature review; these include regeneration of soft tissue, bone, cartilage, and peripheral nerves, as well as wound healing and skin aging.

RESULTS

The reviewed studies demonstrate promising results, with favorable outcomes and minimal complications in the cited cases. In particular, adipose tissue derived stem cell (ADSC) transplants appear to provide effective treatment options for bony and soft tissue defects, and non-healing wounds. ADSCs have also been shown to be useful in aesthetic surgery.

CONCLUSIONS

Further studies involving both the basic and clinical science aspects of stem cell therapies are warranted. In particular, the mechanism of action of stem cells, their interactions with the surrounding microenvironment and their long-term fate require further elucidation. Larger randomized trials are also necessary to demonstrate the continued safety of transplanted stem cells as well as the efficacy of cellular therapies in comparison to the current standards of care.

Neuromodulatory nerve regeneration: adipose tissue-derived stem cells and neurotrophic mediation in peripheral nerve regeneration

Peripheral nerve injury requiring nerve gap reconstruction remains a major problem. In the quest to find an alternative to autogenous nerve graft procedures, attempts have been made to differentiate mesenchymal stem cells into neuronal lineages in vitro and utilize these cellular constructs for nerve regeneration. Unfortunately, this has produced mixed results, with no definitive procedure matching or surpassing traditional nerve grafting procedures. This review presents a different approach to nerve regeneration. The literature was reviewed to evaluate current methods of using adipose-derived stem cells (ADSCs) for peripheral nerve regeneration in in vivo models of animal peripheral nerve injury. The authors present cited evidence for directing nerve regeneration through paracrine effects of ADSCs rather than through in vitro nerve regeneration. The paracrine effects rely mainly, but not solely, on the elaboration of nerve growth factors and neurotrophic mediators that influence surrounding host cells to orchestrate in vivo nerve regeneration. Although this paradigm has been indirectly referred to in a host of publications, few major efforts for this type of neuromodulatory nerve regeneration have been forthcoming. The ADSCs are initially "primed" in vitro using specialized controlled medium (not for neuronal differentiation but for sustainability) and then incorporated into a hydrogel base matrix designed for this purpose. This core matrix is then introduced into a natural collagen-based nerve conduit. The prototype design concepts, evidence for paracrine influences, and regulatory hurdles that are avoided using this approach are discussed.

Suppression of cancer-initiating cells and selection of adipose-derived stem cells cultured on biomaterials having specific nanosegments

Cancer-initiating cells [cancer stem cells (CSCs)] in colon cancer cells can be selectively suppressed when they are cultured on Pluronic (nanosegment)-grafted dishes, whereas CSCs are maintained on conventional tissue culture dishes and extracellular matrix-coated dishes. CSCs persist in tumors as a distinct population and cause relapse and metastasis by giving rise to new tumorigenic clones. The purification or depletion (suppression) of CSCs should be useful for analyzing CSC characteristics and for clinical application. CSCs can be selectively suppressed from colon cancer cells containing adipose-derived stem cells (ADSCs) on Pluronic-grafted dishes, while ADSCs remain on the dishes. ADSCs on Pluronic-grafted dishes after the suppression of the CSCs can differentiate into osteoblasts, chondrocytes, adipocytes, cardiomyocytes, and neuronal cells. The CSCs and ADSCs exhibited different characteristics. The selection of ADSCs was possible on Pluronic-grafted dishes that suppressed the CSCs from the fat tissues of cancer patients (i.e., cell-sorting dishes), which was explained by specific biomedical characteristics of Pluronic.

Characterization of in vitro cultured bone marrow and adipose tissue-derived mesenchymal stem cells and their ability to express neurotrophic factors

MSCs (mesenchymal stem cells) have attracted attention as a promising tool for regenerative medicine and transplantation therapy. MSCs exert neuroprotective effects by secreting a number of factors in vitro and in vivo. Similar characteristics are found in ADSCs (adipose-derived stem cells) and BMSCs (bone marrow stromal cells). Multipotent capability, easy accessibility and rapid proliferation of ADSCs have been established. Our main objective was to compare cell viability, growth rate, expression of neurotrophic factors and nestin genes in ADSCs and BMSCs. Cell doubling time and proliferation rate indicate that ADSCs has a higher proliferation rate than BMSCs. ADSCs and BMSCs express a similar pattern of CD71 and CD90 markers. Nestin immunostaining showed that ADSCs and BMSCs are immunopositive. The expression of neurotrophic factors genes in ADSCs proved similar to that of BMSCs genes. Thus adipose tissue stem cells with a high proliferation rate can express nestin and neurotrophic factor genes. Therefore ADSCs may be useful in future cell replacement therapies and help improve neurodegenerative diseases.

Characteristics of mouse adipose tissue-derived stem cells and therapeutic comparisons between syngeneic and allogeneic adipose tissue-derived stem cell transplantation in experimental autoimmune thyroiditis

Previously, we found that the intravenous administration of human adipose tissue-derived mesenchymal stem cells was a promising therapeutic option for autoimmune thyroiditis even when the cells were transplanted into a xenogeneic model without an immunosuppressant. Therefore, we explored the comparison between the therapeutic effects of syngeneic and allogeneic adipose tissue-derived stem cells on an experimental autoimmune thyroiditis mouse model. Experimental autoimmune thyroiditis was induced in C57BL/6 mice by immunization with porcine thyroglobulin. Adipose tissue-derived stem cells derived from C57BL/6 mice (syngeneic) or BALB/c mice (allogeneic) or saline as a vehicle control were administered intravenously four times weekly. Blood and tissue samples were collected 1 week after the last transplantation. Adipose tissue-derived stem cells from mice were able to differentiate into multiple lineages in vitro; however, mouse adipose tissue-derived stem cells did not have immunophenotypes identical to those from humans. Syngeneic and allogeneic administrations of adipose tissue-derived stem cells reduced thyroglobulin autoantibodies and the inflammatory immune response, protected against lymphocyte infiltration into the thyroid, and restored the Th1/Th2 balance without any adverse effects. However, different humoral immune responses were observed for infused cells from different stem cell sources. The strongest humoral immune response was induced by xenogeneic transplantation, followed by allogeneic and syngeneic administration, in that order. The stem cells were mostly found in the spleen, not the thyroid. This migration might be because the stem cells primarily function in systemic immune modulation, due to being given prior to disease induction. In this study, we confirmed that there were equal effects of adipose tissue-derived stem cells in treating autoimmune thyroiditis between syngeneic and allogeneic transplantations.