Adult mesenchymal stem cells and cell-based tissue engineering

The identification of multipotential mesenchymal stem cells (MSCs) derived from adult human tissues, including bone marrow stroma and a number of connective tissues, has provided exciting prospects for cell-based tissue engineering and regeneration. This review focuses on the biology of MSCs, including their differentiation potentials in vitro and in vivo, and the application of MSCs in tissue engineering. Our current understanding of MSCs lags behind that of other stem cell types, such as hematopoietic stem cells. Future research should aim to define the cellular and molecular fingerprints of MSCs and elucidate their endogenous role(s) in normal and abnormal tissue functions.     

Adult mesenchymal stem cells and cell-based tissue engineering

The identification of multipotential mesenchymal stem cells (MSCs) derived from adult human tissues, including bone marrow stroma and a number of connective tissues, has provided exciting prospects for cell-based tissue engineering and regeneration. This review focuses on the biology of MSCs, including their differentiation potentials in vitro and in vivo, and the application of MSCs in tissue engineering. Our current understanding of MSCs lags behind that of other stem cell types, such as hematopoietic stem cells. Future research should aim to define the cellular and molecular fingerprints of MSCs and elucidate their endogenous role(s) in normal and abnormal tissue functions.     

Plasticity and banking potential of cultured adipose tissue derived mesenchymal stem cells

The present day research on stem cells is yet not filled to the gunwales. The correlation of stem cell technology with tissue repair still has a long way to go. Since Embryonic stem cells are a kind of thorn inside when it comes to therapeutics, there emerged few potent contemporary sources of stem cells. Though bone marrow proves to be the pioneer among these, they lose themselves to adipose tissue in various aspects. The major shortcoming of bone marrow lies in lieu of its loss in potency with age. Adipose tissue puts up a tough competition among leading edge stem cell sources like cord blood and cord matrix. Adipose tissue wins over its counterparts in that it possesses astounding proliferation potency in vitro and holds a prominent stand in showcasing in vivo tissue repair efficacy. In spite of its precedence, the whole enchilada of adipose derived stem cells is still in its salad days. In our work we aim at excogitating the Mesenchymal stem cell population present in cultured adipose derived stem cells, in a wide perspective. Furthermore, the coalition of cell adhesion molecules with the proliferation potency of MSC and analysis of growth curve of ADSC was also paid accolade. The presence of robust MSC with immense differentiation and transdifferentiation potency was endorsed by lucrative differentiation of P3 cells into mesodermal and neuronal lineages. Additionally, mesenchymal stem cells exhibiting coherent expression of surface markers at P3 in all samples can be cryopreserved for therapeutic applications.     

A protocol for umbilical cord tissue cryopreservation as a source of mesenchymal stem cells

Molecular Biology Reports - Mesenchymal stem cells (MSC) differentiate into different cell types and have immunomodulatory and paracrine effects. Cryopreservation of umbilical cord tissue as a...     

Human adipose tissue is a source of multipotent stem cells

Much of the work conducted on adult stem cells has focused on mesenchymal stem cells (MSCs) found within the bone marrow stroma. Adipose tissue, like bone marrow, is derived from the embryonic mesenchyme and contains a stroma that is easily isolated. Preliminary studies have recently identified a putative stem cell population within the adipose stromal compartment. This cell population, termed processed lipoaspirate (PLA) cells, can be isolated from human lipoaspirates and, like MSCs, differentiate toward the osteogenic, adipogenic, myogenic, and chondrogenic lineages. To confirm whether adipose tissue contains stem cells, the PLA population and multiple clonal isolates were analyzed using several molecular and biochemical approaches. PLA cells expressed multiple CD marker antigens similar to those observed on MSCs. Mesodermal lineage induction of PLA cells and clones resulted in the expression of multiple lineage-specific genes and proteins. Furthermore, biochemical analysis also confirmed lineage-specific activity. In addition to mesodermal capacity, PLA cells and clones differentiated into putative neurogenic cells, exhibiting a neuronal-like morphology and expressing several proteins consistent with the neuronal phenotype. Finally, PLA cells exhibited unique characteristics distinct from those seen in MSCs, including differences in CD marker profile and gene expression.     

Age associated communication between cells and matrix: a potential impact on stem cell-based tissue regeneration strategies

A recent paper demonstrated that decellularized extracellular matrix (DECM) deposited by synovium-derived stem cells (SDSCs), especially from fetal donors, could rejuvenate human adult SDSCs in both proliferation and chondrogenic potential, in which expanded cells and corresponding culture substrate (such as DECM) were found to share a mutual reaction in both elasticity and protein profiles (see ref. ¹ Li J, Hansen K, Zhang Y, Dong C, Dinu C, Dzieciatkowska M, Pei M. Rejuvenation of chondrogenic potential in a young stem cell microenvironment. Biomaterials 2014; 35:642-53; PMID: 24148243; http://dx.doi.org/10.1016/j.biomaterials.2013.09.099[Crossref], [PubMed], [Web of Science ®] , [Google Scholar]). It seems that young DECM may assist in the development of culture strategies that optimize proliferation and maintain “stemness” of mesenchymal stem cells (MSCs), helping to overcome one of the primary difficulties in MSC-based regenerative therapies. In this paper, the effects of age on the proliferative capacity and differentiation potential of MSCs are reviewed, along with the ability of DECM from young cells to rejuvenate old cells. In an effort to highlight some of the potential molecular mechanisms responsible for this phenomenon, we discuss age-related changes to extracellular matrix (ECM)'s physical properties and chemical composition.     

Adipose tissue as a potential source of hematopoietic stem/progenitor cells

It has been more than 30 years since adipose tissue (AT) has been recognized as a central modulator orchestrating sophisticated process termed "immunometabolism". Nonetheless, despite its unique involvement in the regulation of immune and endocrine homeostasis, recent studies demonstrated that AT also contains significant number of hematopoietic stem/progenitor cells (HSPCs) that may be there "settling down" throughout life. In this article we will focus on presenting the current concepts regarding endocrine, immunological, and molecular mechanisms that may contribute to and regulate bone marrow (BM)-derived HSPCs homing into AT environment, as well as, highlight various structural and morphological similarities between BM and AT that might be involved in creating appropriate tissue niches for BM-derived HSPCs in AT. Finally, we will discuss how development of obesity or type 2 diabetes may influence balance of homing signals for HSPCs in AT environment.     

Embryonic stem cells as a novel cell source of cell-based biosensors

To investigate the use of embryonic stem cells as biosensor elements, mouse embryoid bodies were cultured on the surface of the light-addressable potentiometric sensor and induce to in vitro differentiate into cardiomyocytes and neurons. Extracellular potentials of the cells were recorded by sensor, to detect stem cells potential applications in drugs screening. The experimental results show that known cardiac stimulants (isoproterenol) and relaxants (carbamylcholine) have characteristic effects on the cardiomyocytes in terms of the changes of beat frequency, amplitude and duration. Thus, the embryonic stem cells potentially represent a renewable cell source for the cell-based biosensors.     

Human amnion-derived mesenchymal stem cells are a potential source for uterine stem cell therapy

Abstract. Objectives: Human amnion is an easy‐to‐obtain novel source of human mesenchymal stem cells, which poses little or no ethical dilemmas. We have previously shown that human amnion‐derived mesenchymal (HAM) cells exhibit certain mesenchymal stem cell‐like characteristics with respect to expression of stem cell markers and differentiation potentials. Materials and methods: In this study, we further characterized HAM cells’ potential for in vivo therapeutic application. Results: Flow cytometric analyses of HAM cells show that they express several stem cell‐related cell surface markers, including CD90, CD105, CD59, CD49d, CD44 and HLA‐ABC, but not CD45, CD34, CD31, CD106 or HLA‐DR. HAM cells at the 10th passage showed normal karyotype. More interestingly, the AbdB‐like HOXA genes HOXA9, HOXA10 and HOXA11 that are expressed in the mesenchyme of the developing female reproductive tract and pregnant uteri are also expressed in HAM cells, suggesting similarities between these two mesenchymal cell types. Progesterone receptor is also highly expressed in HAM cells and expression of genes or proteins in HAM cells could be manipulated with the aid of lentivirus technology or cell‐permeable peptides. To test potentials of HAM cells for in vivo application, we introduced enhanced green fluorescence protein (EGFP)‐expressing HAM cells to mice by intrauterine infusion (into uteri) or by intravenous injection (into the circulation). Presence of EGFP‐expressing cells within the uterine mesenchyme after intrauterine infusion or in lungs after intravenous injection was noted within 1–4 weeks. Conclusions: Collectively, these results suggest that HAM cells are a potential source of mesenchymal stem cells with therapeutic potential.     

The human adipose tissue is a source of multipotent stem cells

Multipotent stem cells constitute an unlimited source of differentiated cells that could be used in pharmacological studies and in medicine. Recently, several publications have reported that adipose tissue contains a population of cells able to differentiate into different cell types including adipocytes, osteoblasts, myoblasts, and chondroblasts. More recently, stem cells with a multi-lineage potential at the single cell level have been isolated from human adipose tissue. These cells, called human Multipotent Adipose-Derived Stem (hMADS) cells, have been established in culture and interestingly, maintain their characteristics with long-term passaging. The adipocyte differentiation of hMADS cells has been thoroughly studied and differentiated cells exhibit the unique feature of human adipocytes. Finally, potential applications of stem cells isolated from adipose tissue in medicine will be discussed.     

Fat tissue: an underappreciated source of stem cells for biotechnology

Adipose tissue can be harvested in large amounts with minimal morbidity. It contains numerous cells types, including adipocytes, preadipocytes, vascular endothelial cells and vascular smooth muscle cells; it also contains cells that have the ability to differentiate into several lineages, such as fat, bone, cartilage, skeletal, smooth, and cardiac muscle, endothelium, hematopoietic cells, hepatocytes and neuronal cells. Cloning studies have shown that some adipose-derived stem cells (ADSCs) have multilineage differentiation potential. ADSCs are also capable of expressing multiple growth factors, including vascular endothelial growth factor and hepatocyte growth factor. Early, uncontrolled, non-randomized clinical research, applying fresh adipose-derived cells into a cranial defect or undifferentiated ADSCs into fistulas in Crohn's disease, has shown healing and an absence of side effects. The combination of these properties, and the large quantity of cells that can be obtained from fat, suggests that this tissue will be a useful tool in biotechnology.     

Osteogenic and adipogenic potential of porcine adipose mesenchymal stem cells

Human, rat, and mouse studies have demonstrated the existence of a population of adipose mesenchymal stem cells (AMSCs) that can undergo multilineage differentiation in vitro. Understanding the clinical potential of AMSCs may require their use in preclinical large-animal models such as pigs. Thus, the objectives of this study were to establish a protocol for the isolation of porcine AMSCs from adipose tissue and to examine their ex vivo differentiation potential to adipocytes and osteoblast. The porcine AMSCs from passage 4 were selected for differentiation analysis. The adipocytes were identified morphologically by staining with Oil Red O, and the adipogenic marker genes were examined by RT-PCR technique. Osteogenic lineage was documented by deposition of calcium stained with Alzarin Red S, visualization of alkaline phosphatase activity, and expression of marker gene. Our result indicates that porcine AMSCs have been successfully isolated and induced differentiation into adipocytes and osteoblasts. This study suggested that porcine AMSCs are also a valuable model system for the study on the mesenchymal lineages for basic research and tissue engineering.     

分离与培养人脂肪组织间充质干细胞的研究

目的：探索人脂肪组织源性间充质干细胞（ASCs）的分离、体外培养,为其广泛应用提供实验依据。方法：无菌条件下获取腹部手术病人皮下脂肪组织,酶消化法分离、培养ASCs,观察细胞形态并绘制细胞生长曲线,计算细胞群体倍增时间;对第2代细胞进行免疫组织化学染色,鉴定其表面分子CD44表达;取2—4代细胞用含体积分数为10％胎牛血清、1％青链霉素原液、1μmmol／L地塞米松、10μmmol／L胰岛素、0．5mmmol／LIBMX的高糖DMEM培养基中诱导培养一周,观察细胞形态变化,并用油红“O”染色定性。结果：人脂肪组织中含有大量间充质干细胞,呈成纤维细胞样贴壁生长,细胞群体倍增时间为55h左右;免疫化学染色鉴定CD44阳性;成脂诱导分化一周,可见细胞内有大量脂滴,油红“0”染色可见胞浆内有大量红染颗粒。结论：建立了一种自人体脂肪组织分离,培养ASCs经济简便的方法,为其能够作为组织工程理想的种子细胞及广泛应用于临床提供实验依据。     

The role of recipient T cells in mesenchymal stem cell-based tissue regeneration

Significant progress has been made in stem cell biology, regenerative medicine, and stem cell-based tissue engineering. Such scientific strides highlight the potential of replacing or repairing damaged tissues in congenital abnormalities, diseases, or injuries, as well as constructing functional tissue or organs in vivo. Since mesenchymal stem cells (MSCs) are capable of differentiating into bone-forming cells, they constitute an appropriate cell source to repair damaged bone tissues. In addition, the immunoregulatory property of MSCs provides a foundation for their use in treating a variety of autoimmune diseases. However, the interaction between MSCs and immune cells in cell-based tissue regeneration is largely unknown. In this review, we will discuss the current understanding of MSC-based tissue regeneration, emphasizing the role of the immune microenvironment in bone regeneration.     

Menstrual blood stem cells as a potential source for cell therapy

Cell replacement and restorative therapies show great promise for the treatment of various diseases and traumas. Various types of stem cells that are rather different in terms of biological properties are evaluated as potential sources for cell therapy. Mesenchymal stem cells (MSCs) display relatively high proliferative activity and high level of plasticity and can be differentiated not only into cells of mesenchymal lineage, but also neurons. Among the MSC populations, the population of endometrial stem cells, including that present in the menstrual blood, is readily available. In the current review, we analyze the biological properties of the menstrual blood stem cells and the possibilities of using them as a potential source for cell therapy.     

Rat extramedullary adipose tissue as a source of osteochondrogenic progenitor cells

Human liposuction aspirates contain pluripotent adipose-derived mesodermal stem cells that have previously been shown to differentiate into various mesodermal cell types, including osteoblasts and chondrocytes. To develop an autologous research model of bone and cartilage tissue engineering, the authors sought to determine whether rat inguinal fat pads contain a similar population of osteochondrogenic precursor cells. It was hypothesized that the rat inguinal fat pad contains adipose-derived multipotential cells that resemble human adipose-derived mesodermal stem cells in their osteochondrogenic capacity. To test this, the authors assessed the ability of cells isolated from the rat inguinal fat pad to differentiate into osteoblasts and chondrocytes by a variety of lineage-specific histologic stains.Rat inguinal fat pads were isolated and processed from Sprague-Dawley rats into a fibroblast-like cell population. Cell cultures were placed in pro-osteogenic media containing dexamethasone, ascorbic acid, and beta-glycerol phosphate. Osteogenic differentiation was assessed at 2, 4, and 6 weeks. Alkaline phosphatase activity and von Kossa staining were performed to assess osteoblastic differentiation and the production of a calcified extracellular matrix. Cell cultures were also placed in prochondrogenic conditions and media supplemented with transforming growth factor-beta1, insulin, transferrin, and ascorbic acid. Chondrogenic differentiation was assessed at 2, 7, and 14 days by the presence of positive Alcian blue staining and type II collagen immunohistochemistry. Cells placed in osteogenic conditions changed in structure to a more cuboidal shape, formed bone nodules, stained positively for alkaline phosphatase activity, and secreted calcified extracellular matrix by 2 weeks. Cells placed in chondrogenic conditions formed cartilaginous nodules within 48 hours that stained positively for Alcian blue and type II collagen. The authors identified the rat inguinal fat pad as a source of osteochondrogenic precursors and developed a straightforward technique to isolate osteochondrogenic precursors from a small animal source. This relatively easily obtained source of osteochondrogenic cells from the rat may be useful for study of tissue engineering strategies and the basic science of stem cell biology.     

大鼠脂肪间充质干细胞诱导为类肝细胞及其细胞片的制备

成体多能干细胞,如来自骨髓和脂肪组织的间充质干细胞等具有多向分化的潜能。虽然自体干细胞移植已经发展成为器官移植的有效代替疗法之一,但是由于移植位点细胞的流失和分化条件的限制等问题使得这种疗法的效率大大降低。本研究目的是将由脂肪干细胞分化而来的类肝细胞制备成具有稳定细胞性状的可移植的肝细胞片。首先在体外分离扩增脂肪干细胞,并通过控制严格地分化条件获得类肝细胞。然后将此细胞接种到聚N-异丙基丙烯酰胺(PNIPAAm)结合的细胞培养皿表面,通过调节培养温度到20oC,使细胞成片脱离培养皿形成细胞片。对细胞片进行了常规HE染色和免疫组化观察,结果显示:这类细胞片中平均含有2～3层细胞,并且保持了细胞外基质的完整。同传统的胰酶消化收集移植用细胞相比,细胞片方法极大地减少了对移植用细胞的细胞膜和细胞外基质的损伤,这将大大促进细胞片和原位组织的相互作用,增加细胞利用效率,从而有望提高治疗效果。     

Isolation of adipose tissue mesenchymal stem cells without tissue destruction: A non-enzymatic method

The conventional enzymatic method is widely used for mesenchymal stem cells (MSCs) isolation from adipose tissue. The method holds major drawbacks; it is costly, time-consuming and results in a heterogeneous cell population. Besides, digestion of extracellular matrix causes cell injury and compromise proliferation and differentiation of the cells. Also, because of over handling the samples are also prone to contamination. Here, we introduce a non-enzymatic method for MSCs isolation without disturbing the cells habitat. Small pieces of adipose tissue obtained from animal or human liposuction were explanted into a culture flask, immobilized by fetal bovine serum (FBS) and incubated overnight. The explants were then irrigated with DMEM containing FBS. Within few days, the fibroblast-like cells migrated from the tissue and proliferated rapidly. When subconfluent, the cells were harvested, expanded through 3 passages and used for immunophenotyping and differentiation assays. As judged by flow cytometric analysis of surface markers (CD44⁺, CD105⁺, CD34⁻, CD45⁻), Oil Red O and Alizarin Red staining, the MSCs isolated by our non-enzymatic method were pluripotent and exhibited the potential for differentiation into adipocyte and osteoblast. Great isolation yields, homogeneity of isolated cells, brief procedure, and high economy are the advantages of our method over the conventional protocol.     

Functional studies of mesenchymal stem cells derived from adult human adipose tissue

Recent evidence suggests that cells with the properties of human mesenchymal stem cells (hMSCs) can be derived from adult peripheral tissues, including adipose tissue, muscle and dermis. We isolated hMSCs from the stromal-vascular portion of subcutaneous adipose tissue from seven adult subjects. These cells could be readily differentiated into cells of the chondrocyte, osteocyte and adipocyte lineage demonstrating their multipotency. We studied the functional properties of hMSCs-derived adipocytes and compared them with adipocytes differentiated from hMSCs obtained from bone marrow (BM-hMSC). The two cell types displayed similar lipolytic capacity upon stimulation with catecholamines, including a pronounced antilipolytic effect mediated through alpha2A-adrenoceptors, a typical trait in human but not rodent fat cells. Furthermore, both cell types secreted the fat cell-specific factors leptin and adiponectin in comparable amounts per time unit. The fat tissue-derived hMSCs retained their differentiation capacity up to at least fifteen passages. We conclude that hMSCs derived from adult human adipose tissue can be differentiated into fully functional adipocytes with a similar, if not identical, phenotype as that observed in cells derived from BM-hMSCs. Human adipose-tissue-derived MSCs could therefore constitute an efficient and easily obtainable renewable cellular source for studies of adipocyte biology.