Adipose Stem Cells and Their Interplay with Cancer Cells and Mitochondrial Reservoir: A New Promising Target.

Adipose-derived stem cells (ASCs) significantly influence tumor progression within the tumor microenvironment (TME). This review examines the pro-tumorigenic roles of ASCs, focusing on paracrine signaling, direct cell-cell interactions, and immunomodulation. ASC-mediated mitochondrial transfer through tunneling nanotubes (TNTs) and gap junctions (GJs) plays a significant role in enhancing cancer cell survival and metabolism. Cancer cells with dysfunctional mitochondria acquire mitochondria from ASCs to meet their metabolic needs and thrive in the TME. Targeting mitochondrial transfer, modulating ASC function, and influencing metabolic pathways are potential therapeutic strategies. However, challenges like TME complexity, specificity, safety concerns, and resistance mechanisms must be addressed. Disrupting the ASC-cancer cell-mitochondria axis offers a promising approach to cancer therapy.

High-throughput single-cell screening of viable hybridomas and patient-derived antibody-secreting cells using punchable microwells.

Monoclonal antibodies (mAbs) hold significant potential as therapeutic agents and are invaluable tools in biomedical research. However, the lack of efficient high-throughput screening methods for single antibody-secreting cells (ASCs) has limited the diversity of available antibodies. Here, we introduce a novel, integrated workflow employing self-seeding microwells and an automated microscope-puncher system for the swift, high-throughput screening and isolation of single ASCs. The system allows for the individual screening and isolation of up to 6,400 cells within approximately one day, with the opportunity for parallelization and efficient upscaling. We successfully applied this workflow to both hybridomas and human patient-derived B cells, enabling subsequent clonal expansion or antibody sequence analysis through an optimized, single-cell nested reverse transcription-polymerase chain reaction (RT-PCR) procedure. By providing a time-efficient and more streamlined single ASC screening and isolation process, our workflow holds promise for driving forward progress in mAb development.

Artificial mitochondrial transplantation (AMT) reverses aging of mesenchymal stromal cells and improves their immunomodulatory properties in LPS-induced synoviocytes inflammation.

Nowadays, regenerative medicine techniques are usually based on the application of mesenchymal stromal cells (MSCs) for the repair or restoration of injured damaged tissues. However, the effectiveness of autologous therapy is limited as therapeutic potential of MSCs declines due to patient's age, health condition and prolonged in vitro cultivation as a result of decreased growth rate. For that reason, there is an urgent need to develop strategies enabling the in vitro rejuvenation of MSCs prior transplantation in order to enhance their in vivo therapeutic efficiency. In presented study, we attempted to mimic the naturally occurring mitochondrial transfer (MT) between neighbouring cells and verify whether artificial MT (AMT) could reverse MSCs aging and improve their biological properties. For that reason, mitochondria were isolated from healthy donor equine adipose-derived stromal cells (ASCs) and transferred into metabolically impaired recipient ASCs derived from equine metabolic syndrome (EMS) affected horses, which were subsequently subjected to various analytical methods in order to verify the cellular and molecular outcomes of the applied AMT. Mitochondria recipient cells were characterized by decreased apoptosis, senescence and endoplasmic reticulum stress while insulin sensitivity was enhanced. Furthermore, we observed increased mitochondrial fragmentation and associated PARKIN protein accumulation, which indicates on the elimination of dysfunctional organelles via mitophagy. AMT further promoted physioxia and regulated autophagy fluxes. Additionally, rejuvenated ASCs displayed an improved anti-inflammatory activity toward LPS-stimulated synoviocytes. The presented findings highlight AMT as a promising alternative and effective method for MSCs rejuvenation, for potential application in autologous therapies in which MSCs properties are being strongly deteriorated due to patients' condition.

Quantifying Human Naïve B Cell Proliferation Kinetics and Differentiation in Controlled In Vitro Cell Culture.

Division tracking dyes like Cell Trace Violet (CTV) enable the quantification of cell proliferation, division, and survival kinetics of human naïve B cell responses in vitro. Human naïve B cells exhibit distinct responses to different stimuli, with CpG and anti-Ig inducing a T cell-independent (TI) response, while CD40L and IL-21 promote a T cell-dependent (TD) response that induces isotype switching and differentiation into antibody-secreting cells (ASCs). Both stimulation methods yield valuable insights into the intrinsic programming of B cell health within individuals, making them useful for clinical investigations. For instance, quantitative analysis from these B cell populations could reveal biologically meaningful measurements such as the average number of division rounds and the time to cells' fate. Here, we describe a novel in vitro culture setup for CTV-labelled human naïve B cells and a method for obtaining precise time-based data on proliferation, division-linked isotype switching, and differentiation.

Isolation of the Stromal Vascular Fraction Using a New Protocol with All Clinical-Grade Drugs: From Basic Study to Clinical Application.

OBJECTIVE: The purpose of this study was to evaluate the yield, viability, clinical safety, and efficacy of the stromal vascular fraction (SVF) separated with a new protocol with all clinical-grade drugs. MATERIALS AND METHODS: SVF cells were isolated from lipoaspirate obtained from 13 participants aged from 30 to 56 years by using a new clinical protocol and the laboratory protocol. The cell yield, viability, morphology, mesenchymal stem cell (MSC) surface marker expression, and differentiation abilities of the SVF cells harvested from the two protocols were compared. Furthermore, three related clinical trials were conducted to verify the safety and efficiency of SVF cells isolated by the new clinical protocol. RESULTS: There were no significant differences in the yield, viability, morphology, and differentiation potential of the SVFs isolated with the clinical protocol and laboratory protocol. Adipose-derived mesenchymal stem cell (ASC) surface marker expression, including that of CD14, CD31, CD44, CD90, CD105, and CD133, was consistent between the two protocols. Clinical trials have demonstrated the effectiveness of the SVF isolated with the new clinical protocol in improving skin grafting, promoting mechanical stretch-induced skin regeneration and improving facial skin texture. No complications occurred. CONCLUSION: SVF isolated by the new clinical protocol had a noninferior yield and viability to that of the SVF separated by the laboratory protocol. SVFs obtained by the new protocol can be safely and effectively applied to improve skin grafting, promote mechanical stretch-induced skin regeneration, and improve facial skin texture. TRIAL REGISTRATION: The trials were registered with the ClinicalTrials.gov (NCT03189628), the Chinese Clinical Trial Registry (ChiCTR2000039317), and the ClinicalTrials.gov (NCT02546882). All the three trials were not patient-funded trials. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

A Computationally Optimized Broadly Reactive Hemagglutinin and Neuraminidase Vaccine Boosts Antibody-Secreting Cells and Induces a Robust Serological Response, Preventing Lung Damage in a Pre-Immune Model.

The hemagglutinin (HA) and neuraminidase (NA) surface proteins are the primary and secondary immune targets for most influenza vaccines. In this study, H2, H5, H7, N1, and N2 antigens designed by the computationally optimized broadly reactive antigen (COBRA) methodology were incorporated into an adjuvant-formulated vaccine to assess the protective efficacy and immune response against A/Hong Kong/125/2017 H7N9 virus challenge in pre-immune mice. The elicited antibodies bound to H2, H5, H7, N1, and N2 wild-type antigens; cH6/1 antigens; and cH7/3 antigens, with hemagglutinin inhibition (HAI) activity against broad panels of the H2Nx, H5Nx, and H7Nx influenza strains. Mice vaccinated with the pentavalent COBRA HA/NA vaccine showed little to no weight loss, no clinical signs of diseases, and were protected from mortality when challenged with the lethal H7N9 virus. Virus titers in the lungs of vaccinated mice were lower and cleared more rapidly than in mock-vaccinated mice. Some vaccinated mice showed no detectable lung injury or inflammation. Antibody-secreting cells were significantly increased in COBRA-vaccinated mice, with higher total Ig and H7-specific ASC. Thus, the combination of H2, H5, H7, N1, and N2 COBRA antigens presents a potential for the formulation of a universal influenza virus vaccine.

Pilot Study for Isolation of Stromal Vascular Fraction with Collagenase Using an Automated Processing System.

There are many potential therapeutic applications for autologous adipose-derived stromal cells. These cells are found in a heterogeneous population isolated from adipose tissue called the stromal vascular fraction (SVF). Closed automated systems are available to release cells from the adherent stroma. Here, we test one system to evaluate the heterogeneous output for yield, purity, cellular characterization, and stemness criteria. The SVF was isolated from three donors using the Automated Cell Station (ACS) from BSL Co., Ltd., Busan, Republic of Korea. The SVF cellular output was characterized for cell yield and viability, immunophenotyping analysis, pluripotent differentiation potential, adhesion to plastic, and colony-forming units. Additionally, the SVF was tested for endotoxin and collagenase residuals. The SVF yield from the ACS system was an average volume of 7.9 ± 0.5 mL containing an average of 19 × 106 nucleated cells with 85 ± 12% viability. Flow cytometry identified a variety of cells, including ASCs (23%), macrophages (24%), endothelial cells (5%), pericytes (4%), and transitional cells (0.5%). The final concentrated product contained cells capable of differentiating into adipogenic, chondrogenic, and osteogenic phenotypes. Furthermore, tests for SVF sterility and purity showed no evidence of endotoxin or collagenase residuals. The ACS system can efficiently process cells from adipose tissue within the timeframe of a single surgical procedure. The cellular characterization indicated that this system can yield a sterile and concentrated SVF output, providing a valuable source of ASCs within the heterogeneous cell population.

Navigating the Adipocyte Precursor Niche: Cell-Cell Interactions, Regulatory Mechanisms and Implications for Adipose Tissue Homeostasis.

Support for stem cell self-renewal and differentiation hinges upon the intricate microenvironment termed the stem cell 'niche'. Within the adipose tissue stem cell niche, diverse cell types, such as endothelial cells, immune cells, mural cells, and adipocytes, intricately regulate the function of adipocyte precursors. These interactions, whether direct or indirect, play a pivotal role in governing the balance between self-renewal and differentiation of adipocyte precursors into adipocytes. The mechanisms orchestrating the maintenance and coordination of this niche are still in the early stages of comprehension, despite their crucial role in regulating adipose tissue homeostasis. The complexity of understanding adipocyte precursor renewal and differentiation is amplified due to the challenges posed by the absence of suitable surface receptors for identification, limitations in creating optimal ex vivo culture conditions for expansion and constraints in conducting in vivo studies. This review delves into the current landscape of knowledge surrounding adipocyte precursors within the adipose stem cell niche. We will review the identification of adipocyte precursors, the cell-cell interactions they engage in, the factors influencing their renewal and commitment toward adipocytes and the transformations they undergo during instances of obesity.

Sex hormone binding globulin (SHBG) modulates mitochondrial dynamics in PPARγ-depleted equine adipose derived stromal cells.

Peroxisome proliferator-activated receptor gamma (PPARγ) is a transcription factor that promotes adipogenesis, lipid uptake and storage, insulin sensitivity, and glucose metabolism. Hence, defects in PPARγ have been associated to the development of metabolic disorders. Sex hormone-binding globulin (SHBG) is a glycoprotein primarily produced in the liver that regulates the bioavailability of sex hormones. Alike PPARγ, low SHBG levels have been correlated with insulin resistance and associated endocrine abnormalities. Therefore, this study aimed to verify whether SHBG may restore depleted PPARγ functions and thus serve as a new candidate for the management of metabolic conditions. A model of equine adipose-derived stromal cells (EqASCs) has been used, in which a PPARγ silencing and SHBG treatment have been achieved to determine the changes in cell viability, premature senescence, oxidative stress, and mitochondrial functions. Obtained data demonstrated that loss in PPARγ triggers cell apoptosis which is not reversed by SHBG application. Moreover, PPARγ knockdown cells exhibited premature senescence, which has been substantially alleviated by SHBG concomitantly to increased BAX/BCL2 ratio, suggesting a possible effect on senescence-induced apoptosis resistance. Interestingly, PPARγ silencing induced a significant alteration in mitochondrial membrane potential as well as the expression of dynamics and metabolism-related markers. SHBG treatment enabled to ameliorate the transmembrane potential, to normalize the expression levels of key dynamics and metabolism mediators, and to restore the protein levels of PINK, which is critically involved in mitochondria recycling machinery. Presented data suggest that SHBG may provide new mechanistic insights into the regulation of PPARγ functions, and thus offers a preliminary picture on a possible SHBG-PPARγ metabolic crosstalk. KEY MESSAGES : PPARγ is a transcription factor that tightly regulates cell metabolism. Low SHBG levels correlate with insulin resistance and associated endocrine abnormalities. PPARγ silencing reduces cell viability, triggers premature senescence and profound mitochondrial failure in equine ASCs. SHBG protein reverses senescent phenotype and apoptosis resistance of PPARγ- ASCs. SHBG improves mitochondrial dynamics and metabolism following PPARγ knockdown. SHBG might serve as a PPARγ potential mimicking agent for the modulation of ASCs metabolic processes.

Evaluation of adipose-derived stem cells (ASCS) exosome implantation and platelet-rich fibrin (PRF) on critical long bone defects in Sprague-Dawley rats.

INTRODUCTION: This study aimed to assess the efficacy of adipose-derived mesenchymal stem cell exosomes (ASCs exosome) and platelet-rich fibrin (PRF) in treating critical long bone defects in Sprague-Dawley rats. Critical long bone defects, defined as exceeding 2 cm or 50% of the bone diameter, often pose a healing challenge. While autologous bone grafts have been considered, they have shown unreliable results and donor-site complications, necessitating alternative treatments. METHODS: The research followed a quasi-experimental post-test only control group design involving 30 male Sprague-Dawley rats. The rats were divided into five groups and subjected to femur bone defect creation, internally fixed with a 1.4 mm K-wire, and treated with various combinations of hydroxyapatite (HA), bone graft (BG), ASCs exosome, and PRF. Histomorphometry and BMP-2 gene expression analysis were performed to evaluate bone healing. RESULTS AND DISCUSSION: The results indicated that the group treated with HA + BG + ASCs exosome (group IV) exhibited the highest BMP-2 gene expression, while group III (HA + BG + ASCs exosome + PRF) had the highest chordin level. Overall, groups receiving ASCs exosome or PRF intervention showed elevated BMP-2 expression compared to the control group. The use of ASCs exosome and PRF showed comparable outcomes compared to bone graft administration in terms of histomorphometry analysis. CONCLUSION: The administration of adipose tissue derived mesenchymal stem cells and PRF has a comparable outcome with the use of bone graft in terms of osseus area and expression of BMP-2 in critical bone defect.

The Expression of Adipogenic Marker Is Significantly Increased in Estrogen-Treated Lipedema Adipocytes Differentiated from Adipose Stem Cells In Vitro.

Lipedema is a chronic, idiopathic, and painful disease characterized by an excess of adipose tissue in the extremities. The goal of this study is to characterize the gene expression of estrogen receptors (ERα and ERß), G protein-coupled estrogen receptor (GPER), and ER-metabolizing enzymes: hydroxysteroid 17-beta dehydrogenase (HSD17B1, 7, B12), cytochrome P450 (CYP19A1), hormone-sensitive lipase (LIPE), enzyme steroid sulfatase (STS), and estrogen sulfotransferase (SULT1E1), which are markers in Body Mass Index (BMI) and age-matched non-lipedema (healthy) and lipedema ASCs and spheroids. Flow cytometry and cellular proliferation assays, RT-PCR, and Western Blot techniques were used to determine the expression of ERs and estrogen-metabolizing enzymes. In 2D monolayer culture, estrogen increased the proliferation and the expression of the mesenchymal marker, CD73, in hormone-depleted (HD) healthy ASCs compared to lipedema ASCs. The expression of ERß was significantly increased in HD lipedema ASCs and spheroids compared to corresponding healthy cells. In contrast, ERα and GPER gene expression was significantly decreased in estrogen-treated lipedema spheroids. CYP19A1 and LIPE gene expressions were significantly increased in estrogen-treated healthy ASCs and spheroids, respectively, while estrogen upregulated the expression of PPAR-ϒ2 and ERα in estrogen-treated lipedema-differentiated adipocytes and spheroids. These results indicate that estrogen may play a role in adipose tissue dysregulation in lipedema.

Rapid generation of human recombinant monoclonal antibodies from antibody-secreting cells using ferrofluid-based technology.

Monoclonal antibodies (mAbs) are one of the most important classes of biologics with high therapeutic and diagnostic value, but traditional methods for mAbs generation, such as hybridoma screening and phage display, have limitations, including low efficiency and loss of natural chain pairing. To overcome these challenges, novel single B cell antibody technologies have emerged, but they also have limitations such as in vitro differentiation of memory B cells and expensive cell sorters. In this study, we present a rapid and efficient workflow for obtaining human recombinant monoclonal antibodies directly from single antigen-specific antibody secreting cells (ASCs) in the peripheral blood of convalescent COVID-19 patients using ferrofluid technology. This process allows the identification and expression of recombinant antigen-specific mAbs in less than 10 days, using RT-PCR to generate linear Ig heavy and light chain gene expression cassettes, called "minigenes", for rapid expression of recombinant antibodies without cloning procedures. This approach has several advantages. First, it saves time and resources by eliminating the need for in vitro differentiation. It also allows individual antigen-specific ASCs to be screened for effector function prior to recombinant antibody cloning, enabling the selection of mAbs with desired characteristics and functional activity. In addition, the method allows comprehensive analysis of variable region repertoires in combination with functional assays to evaluate the specificity and function of the generated antigen-specific antibodies. Our approach, which rapidly generates recombinant monoclonal antibodies from single antigen-specific ASCs, could help to identify functional antibodies and deepen our understanding of antibody dynamics in the immune response through combined antibody repertoire sequence analysis and functional reactivity testing.

Mesenchymal stem cells in autoimmune disease: A systematic review and meta-analysis of pre-clinical studies.

Mesenchymal Stem Cells (MSCs) are of interest in the clinic because of their immunomodulation capabilities, capacity to act upstream of inflammation, and ability to sense metabolic environments. In standard physiologic conditions, they play a role in maintaining the homeostasis of tissues and organs; however, there is evidence that they can contribute to some autoimmune diseases. Gaining a deeper understanding of the factors that transition MSCs from their physiological function to a pathological role in their native environment, and elucidating mechanisms that reduce their therapeutic relevance in regenerative medicine, is essential. We conducted a Systematic Review and Meta-Analysis of human MSCs in preclinical studies of autoimmune disease, evaluating 60 studies that included 845 patient samples and 571 control samples. MSCs from any tissue source were included, and the study was limited to four autoimmune diseases: multiple sclerosis, rheumatoid arthritis, systemic sclerosis, and lupus. We developed a novel Risk of Bias tool to determine study quality for in vitro studies. Using the International Society for Cell & Gene Therapy's criteria to define an MSC, most studies reported no difference in morphology, adhesion, cell surface markers, or differentiation into bone, fat, or cartilage when comparing control and autoimmune MSCs. However, there were reported differences in proliferation. Additionally, 308 biomolecules were differentially expressed, and the abilities to migrate, invade, and form capillaries were decreased. The findings from this study could help to explain the pathogenic mechanisms of autoimmune disease and potentially lead to improved MSC-based therapeutic applications.

Extracellular Vesicles Isolated from Equine Adipose-Derived Stromal Stem Cells (ASCs) Mitigate Tunicamycin-Induced ER Stress in Equine Corneal Stromal Stem Cells (CSSCs).

Corneal ulcers, characterized by severe inflammation of the cornea, can lead to serious, debilitating complications and may be vision-threatening for horses. In this study, we aimed to investigate the role of endoplasmic reticulum (ER) stress in corneal stem progenitor cell (CSSC) dysfunction and explore the potential of equine adipose-derived stromal stem cell (ASC)-derived extracellular vesicles (EVs) to improve corneal wound healing. We showed that CSSCs expressed high levels of CD44, CD45, and CD90 surface markers, indicating their stemness. Supplementation of the ER-stress-inducer tunicamycin to CSSCs resulted in reduced proliferative and migratory potential, accumulation of endoplasmic reticulum (ER)-stressed cells in the G0/G1 phase of the cell cycle, increased expression of proinflammatory genes, induced oxidative stress and sustained ER stress, and unfolded protein response (UPR). Importantly, treatment with EVs increased the proliferative activity and number of cells in the G2/Mitosis phase, enhanced migratory ability, suppressed the overexpression of proinflammatory cytokines, and upregulated the anti-inflammatory miRNA-146a-5p, compared to control and/or ER-stressed cells. Additionally, EVs lowered the expression of ER-stress master regulators and effectors (PERK, IRE1, ATF6, and XBP1), increased the number of mitochondria, and reduced the expression of Fis-1 and Parkin, thereby promoting metabolic homeostasis and protecting against apoptosis in equine CSSCs. Our findings demonstrate that MSCs-derived EVs represent an innovative and promising therapeutic strategy for the transfer of bioactive mediators which regulate various cellular and molecular signaling pathways.

Advanced methods to mechanically isolate stromal vascular fraction: A concise review.

Adipose tissue is a highly attractive reservoir of stem cells due to its accessibility and abundance, and the SVF within it holds great promise for stem cell-based therapies. The use of mechanical methods for SVF isolation from adipose tissue is preferred over enzymatic methods, as it can be readily applied in clinical settings without additional processing steps. However, there is a lack of consensus on the optimal approach for mechanically isolating SVF. This comprehensive review aims to present and compare the latest mechanical isolation methods for SVF from adipose tissue, including centrifugation, filtration/washing, emulsification, vibration, and mincing/adiponizing. Each of these methods possesses unique advantages and limitations, and yet, no conclusive evidence has emerged demonstrating the superiority of one approach over the others, primarily due to the dearth of well-controlled prospective studies in this field.

Near-infrared-II fluorescence/magnetic resonance double modal imaging of transplanted stem cells using lanthanide co-doped gadolinium oxide nanoparticles.

To ensure maximum therapeutic safety and efficacy of stem cell transplantation, it is essential to observe the kinetics of behavior, accumulation, and engraftment of transplanted stem cells in vivo. However, it is difficult to detect transplanted stem cells with high sensitivity by conventional in vivo imaging technologies. To diagnose the kinetics of transplanted stem cells, we prepared multifunctional nanoparticles, Gd2O3 co-doped with Er3+ and Yb3+ (Gd2O3: Er, Yb-NPs), and developed an in vivo double modal imaging technique with near-infrared-II (NIR-II) fluorescence imaging and magnetic resonance imaging (MRI) of stem cells using Gd2O3: Er, Yb-NPs. Gd2O3: Er, Yb-NPs were transduced into adipose tissue-derived stem cells (ASCs) through a simple incubation process without cytotoxicity under certain concentrations of Gd2O3: Er, Yb-NPs and were found not to affect the morphology of ASCs. ASCs labeled with Gd2O3: Er, Yb-NPs were transplanted subcutaneously onto the backs of mice, and successfully imaged with good contrast using an in vivo NIR-II fluorescence imaging and MRI system. These data suggest that Gd2O3: Er, Yb-NPs may be useful for in vivo double modal imaging with NIR-II fluorescence imaging and MRI of transplanted stem cells.

Isolation of Human Adipose-Derived Stromal/Stem Cells from Lipoaspirates.

Adipose tissue is an abundant and accessible source of stem cells with multipotent properties suitable for tissue engineering and regenerative medical applications. Adipose-derived stromal/stem cells (ASCs) have been widely used in tissue engineering and cell therapy. In addition, the clinical application of ASCs in the treatment of inflammation and injury has been proven a success. Here, we describe methods from our own laboratory and the literature for the isolation and expansion of Adipose-derived stromal/stem cells (ASCs). We present a large-scale procedure suitable for processing >100 mL volumes of lipoaspirate tissue specimens by collagenase digestion, a related procedure suitable for processing adipose tissue aspirates without digestion, and a procedure suitable for intact human adipose tissue, such as buccal fat pads in the maxillofacial region.

Isolation of Human Adipose-Derived Stem Cells.

Human adipose-derived stromal/stem cells (hASCs) are a promising source of adult stem cells used in numerous applications in regenerative medicine. We present the protocols from our laboratory for isolating and expanding hASCs. The isolation of hASCs involves the enzymatic digestion of adipose tissue and subsequent culturing of the isolated cells.

Isolation of Murine Adipose-Derived Stromal/Stem Cells for Adipogenic and Osteogenic Differentiation or Flow Cytometry-Based Analysis.

Murine models of obesity or reduced adiposity are a valuable resource for understanding the role of adipocyte dysfunction in metabolic disorders. Adipose tissue stromal vascular cells or primary adipocytes derived from murine adipose tissue and grown in culture are essential tools for studying the mechanisms underlying adipocyte development and function. Herein, we describe methods for the isolation, expansion, and long-term storage of murine adipose-derived stromal/stem cells, along with protocols for inducing adipogenesis to white or beige adipocytes in this cell population and osteogenic differentiation. Isolation of the adipose stromal vascular fraction cells for flow cytometric analysis is also described.

Isolation of Murine Adipose-Derived Stromal/Stem Cells Using an Explant Culture Method.

Adipose tissue provides a valuable cell source for tissue engineering, regenerative medicine, and adipose tissue biology studies. The most widely used adipose-derived stromal/stem cells (ASCs) isolation protocol involves enzymatic digestion with collagenase. However, the yield of the method often proves to be poor if not impossible for collection of sufficient stromal vascular fraction (SVF) for expansion when the sample size is small, for instance when only newborn mice are available for cell culture. Here, we describe an efficient protocol for the isolation and expansion of ASCs using explant culture as an alternative. Briefly, adipose tissue was minced after removing excess liquid. Then, the minced tissue was placed in culture dishes or flasks. The cells will migrate out of tissue and adhere to the culture surface after one or more days.