Purification of human adipose-derived stem cells from fat tissues using PLGA/silk screen hybrid membranes

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.

Manufacturing and banking canine adipose-derived mesenchymal stem cells for veterinary clinical application

BACKGROUND

Mesenchymal stem cells (MSCs) have generated a great amount of interest in recent years as a novel therapeutic application for improving the quality of pet life and helping them free from painful conditions and diseases. It has now become critical to address the challenges related to the safety and efficacy of MSCs expanded in vitro. In this study, we establish a standardized process for manufacture of canine adipose-derived MSCs (AD-MSCs), including tissue sourcing, cell isolation and culture, cryopreservation, thawing and expansion, quality control and testing, and evaluate the safety and efficacy of those cells for clinical applications.

RESULTS

After expansion, the viability of AD-MSCs manufactured under our standardized process was above 90 %. Expression of surface markers and differentiation potential was consistent with ISCT standards. Sterility, mycoplasma, and endotoxin tests were consistently negative. AD-MSCs presented normal karyotype, and did not form in vivo tumors. No adverse events were noted in the case treated with intravenously AD-MSCs.

CONCLUSIONS

Herein we demonstrated the establishment of a feasible bioprocess for manufacturing and banking canine AD-MSCs for veterinary clinical use.

Adipose tissue-derived stem cells: a comparative review on isolation, culture, and differentiation methods

Adipose tissue-derived stem cells (ADSCs) are an available source of mesenchymal stem cells with the appropriate capacity to in vitro survive, propagate, and differentiate into cells from three lineages of ectoderm, mesoderm, and endoderm. The biological features of ADSCs depend on the donor physiology and health status, isolation procedure, culture conditions, and differentiation protocols used. Adipose tissue samples are provided by surgery and lipoaspiration-based methods and subjected to various mechanical and chemical digestion techniques to finally generate a heterogeneous mixture named stromal vascular fraction (SVF). ADSCs are purified through varied cell populations that exist within SVF and cultured under standard conditions to give rise to a highly rich resource of stem cells directly applied in the clinic or differentiated into a wide range of cells. The development and optimization of conventional isolation, expansion, and differentiation methods seem noteworthy to preserve the desirable biological functions of ADSCs in pre-clinical and clinical investigations.

MicroRNA-124-3p affects myogenic differentiation of adipose-derived stem cells by targeting Caveolin-1 during pelvic floor dysfunction in Sprague Dawley rats

Background

The aim of this study was to investigate using myogenic differentiation of adipose stem cells for the treatment of female pelvic floor dysfunction (PFD) and aimed to further study the influences of microRNA-124-3p (miR-124-3p) in the process of myogenic differentiation of adipose-derived stem cells (ADSCs) through targeting Caveolin-1 (Cav1) during PFD in Sprague Dawley (SD) rats.

Methods

The ADSCs were separated from 6–8-week-old female SD rats (n=25) and were cultivated. Then, we observed the cell status and conducted fat and osteogenic experiments. We then constructed an ADSC-green fluorescent protein (GFP) stable transfer strain. Flow cytometry was used to identify the positive rates of CD44, CD90, and CD45 in ADSCs and ADSC-GFP. Real-time quantitative polymerase chain reaction (qRT-PCR) and western blotting were used to mRNA and protein expression levels. Myogenic differentiation of ADSCs was measured with immunofluorescence methods. A dual-luciferase reporter assay was executed to affirm whether Cav1 was a target of miR-124-3p.

Results

The isolated ADSCs cells were in good condition under the microscope. The results of flow cytometry showed that the positive rate of CD44 and CD90 was high, and the positive rate of CD45 was low in ADSCs and ADSC-GFP. Under normal culture conditions, ADSCs-GFP cells can be massively adipated and osteogenic. After 5-Aza induced ADSC-GFP myogenic differentiation, the level of miR-124-3p was significantly increased. We found that MiR-124-3p mimics promoted the myogenic differentiation of ADSCs. Moreover, we discovered that Cav1 was a target gene of miR-124-3p and was negatively regulated by miR-124-3p. The results of leak point pressure (LPP), hematoxylin and eosin (HE), and Masson showed that the collagen fiber content of the PFD group was lower than that of the control group; the collagen fiber content of ADSC-GFP, 5-Aza, or miR-124-3p mimics were increased after intervention. Furthermore, the outcomes qRT-PCR, western blotting, and immunofluorescence suggested that miR-124-3p facilitated the survival ADSC-GFP fat transplantation by regulating many key factors in vivo.

Conclusions

These results proofed that miR-124-3p could accelerate myogenic differentiation of ADSCs by down-regulating Cav1 to improve PFD in SD rats, which will pave the way for therapeutic delivery of miRNA targeting PFD disease.

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.

Stem cell therapies for myocardial infarction in clinical trials: bioengineering and biomaterial aspects

Cardiovascular disease remains the leading cause of death and disability in advanced countries. Stem cell transplantation has emerged as a promising therapeutic strategy for acute and chronic ischemic cardiomyopathy. The current status of stem cell therapies for patients with myocardial infarction is discussed from a bioengineering and biomaterial perspective in this review. We describe (a) the current status of clinical trials of human pluripotent stem cells (hPSCs) compared with clinical trials of human adult or fetal stem cells, (b) the gap between fundamental research and application of human stem cells, (c) the use of biomaterials in clinical and pre-clinical studies of stem cells, and finally (d) trends in bioengineering to promote stem cell therapies for patients with myocardial infarction. We explain why the number of clinical trials using hPSCs is so limited compared with clinical trials using human adult and fetal stem cells such as bone marrow-derived stem cells.

Stem Cell Therapies for Reversing Vision Loss

Current clinical trials that evaluate human pluripotent stem cell (hPSC)-based therapies predominantly target treating macular degeneration of the eyes because the eye is an isolated tissue that is naturally weakly immunogenic. Here, we discuss current bioengineering approaches and biomaterial usage in combination with stem cell therapy for macular degeneration disease treatment. Retinal pigment epithelium (RPE) differentiated from hPSCs is typically used in most clinical trials for treating patients, whereas bone marrow mononuclear cells (BMNCs) or mesenchymal stem cells (MSCs) are intravitreally transplanted, undifferentiated, into patient eyes. We also discuss reported negative effects of stem cell therapy, such as patients becoming blind following transplantation of adipose-derived stem cells, which are increasingly used by 'stem-cell clinics'.

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.

Proliferation and osteogenic differentiation of amniotic fluid-derived stem cells

The osteogenic differentiation of stem cells.

Three-Dimensional Stem Cell Bioprinting

Stem cells have become a revived biotechnology that is beginning to expand the field of regenerative medicine. Although stem cells are capable of regenerating tissues, current research trends tend to side on developing fully functional organs and other clinical uses including in situ stem cell repair through three-dimensional printing methods. Through several tests and techniques, it can be shown that most stem cell printing methods are possible and that most tests come out with high cell viability. Furthermore, the importance of bioprinting is to benefit the field of regenerative medicine, which looks into artificial organ transplants for the thousands of patients without donors. Although the field is not brand new, understanding the integration and use of additive manufacturing with biomaterials is essential in developing fully functional organs. There is a heavy emphasis on the biomaterials themselves since they have a crucial role in creating an organ that is mechanically robust and adaptable in vivo. Covered in this review article are many featured tests, which also touch on the importance of including a biomaterial that is capable of maintaining a viable microenvironment. These include biomaterials such as hydrogels, biopolymers, and synthetic extra cellular matrices (ECM) built for stem cells to proliferate, differentiate, and give freedom to cell communication after printing.

A hybrid-membrane migration method to isolate high-purity adipose-derived stem cells from fat tissues

Human adipose-derived stem cells (hADSCs) exhibit heterogeneous characteristics, indicating various genotypes and differentiation abilities. The isolated hADSCs can possess different purity levels and divergent properties depending on the purification methods used. We developed a hybrid-membrane migration method that purifies hADSCs from a fat tissue solution with extremely high purity and pluripotency. A primary fat-tissue solution was permeated through the porous membranes with a pore size from 8 to 25 μm, and the membranes were incubated in cell culture medium for 15-18 days. The hADSCs that migrated from the membranes contained an extremely high percentage (e.g., >98%) of cells positive for mesenchymal stem cell markers and showed almost one order of magnitude higher expression of some pluripotency genes (Oct4, Sox2, Klf4 and Nanog) compared with cells isolated using the conventional culture method.

Pluripotency maintenance of amniotic fluid-derived stem cells cultured on biomaterials

Human amniotic fluid-derived stem cells can maintain their pluripotency when cultured on soft hydrogels.