Obesity Determines the Immunophenotypic Profile and Functional Characteristics of Human Mesenchymal Stem Cells From Adipose Tissue

Therapeutic Evidence of Human Mesenchymal Stem Cell Transplantation for Cerebral Palsy: A Meta-Analysis of Randomized Controlled Trials

Cerebral palsy (CP) is a kind of movement and posture disorder syndrome in early childhood. In recent years, human mesenchymal stem cell (hMSC) transplantation has become a promising therapeutic strategy for CP. However, clinical evidence is still limited and controversial about clinical efficacy of hMSC therapy for CP. Our aim is to evaluate the efficacy and safety of hMSC transplantation for children with CP using a meta-analysis of randomized controlled trials (RCTs). We conducted a systematic literature search including Embase, PubMed, ClinicalTrials.gov, Cochrane Controlled Trials Register databases, Chinese Clinical Trial Registry, and Web of Science from building database to February 2020. We used Cochrane bias risk assessment for the included studies. The result of pooled analysis showed that hMSC therapy significantly increased gross motor function measure (GMFM) scores (standardized mean difference (SMD) = 1.10, 95%CI = 0.66‐1.53, P < 0.00001, high-quality evidence) and comprehensive function assessment (CFA) (SMD = 1.30, 95%CI = 0.71‐1.90, P < 0.0001, high-quality evidence) in children with CP, compared with the control group. In the subgroup analysis, the results showed that hMSC therapy significantly increased GMFM scores of 3, 6, and 12 months and CFA of 3, 6, and 12 months. Adverse event (AE) of upper respiratory infection, diarrhea, and constipation was not statistically significant between the two groups. This meta-analysis synthesized the primary outcomes and suggested that hMSC therapy is beneficial, effective, and safe in improving GMFM scores and CFA scores in children with CP. In addition, subgroup analysis showed that hMSC therapy has a lasting positive benefit for CP in 3, 6, and 12 months.

Microbial Signature in Adipose Tissue of Crohn's Disease Patients

Crohn’s disease (CD) is characterized by compromised immune tolerance to the intestinal commensal microbiota, intestinal barrier inflammation, and hyperplasia of creeping fat (CF) and mesenteric adipose tissue (AT), which seems to be directly related to disease activity. Gut microbiota dysbiosis might be a determining factor in CD etiology, manifesting as a low microbial diversity and a high abundance of potentially pathogenic bacteria. We tested the hypothesis that CF is a reservoir of bacteria through 16S-rRNA sequencing of several AT depots of patients with active and inactive disease and controls. We found a microbiome signature within CF and mesenteric AT from patients, but not in subcutaneous fat. We failed to detect bacterial DNA in any fat depot of controls. Proteobacteria was the most abundant phylum in both CF and mesenteric AT, and positively correlated with fecal calprotectin/C-reactive protein. Notably, the clinical status of patients seemed to be related to the microbiome signature, as those with the inactive disease showed a reduction in the abundance of pathogenic bacteria. Predictive functional profiling revealed many metabolic pathways including lipopolysaccharide biosynthesis and sulfur metabolism overrepresented in active CD relative to that in inactive CD. Our findings demonstrate that microbiota dysbiosis associated with CD pathophysiology is reflected in AT and might contribute to disease severity.

Adipose Tissue-Derived Stem Cells from Type 2 Diabetics Reveal Conservative Alterations in Multidimensional Characteristics

Background and Objectives

Adipose tissue-derived mesenchymal stem cells (ASCs) are recognized as an advantaged source for the prevention and treatment of diverse diseases including type 2 diabetes mellitus (T2DM). However, alterations in characteristics of ASCs from the aforementioned T2DM patients are still obscure, which also hinder the rigorous and systematic illumination of progression and pathogenesis.

Methods and Results

In this study, we originally isolated peripancreatic adipose tissue-derived mesenchymal stem cells from both human type 2 diabetic and non-diabetic donors (T2DM-ASCs, ND-ASCs) with the parental consent, respectively. We noticed that T2DM-ASCs exhibited indistinguishable immunophenotype, cell vitality, chondrogenic differentiation and stemness as ND-ASCs. Simultaneously, there’s merely alterations in migration and immunoregulatory capacities in T2DM-ASCs. However, differing from ND-ASCs, T2DM-ASCs exhibited deficiency in adipogenic and osteogenic differentiation, and in particular, the delayed cell cycle and different cytokine expression spectrum.

Conclusions

The conservative alterations of T2DM-ASCs in multifaceted characteristics indicated the possibility of autologous application of ASCs for cell-based T2DM treatment in the future.

Weighing the Risk: effects of Obesity on the Mammary Gland and Breast Cancer Risk

Obesity is a preventable risk factor for breast cancer following menopause. Regardless of menopausal status, obese women who develop breast cancer have a worsened prognosis. Breast tissue is comprised of mammary epithelial cells organized into ducts and lobules and surrounded by adipose-rich connective tissue. Studies utilizing multiple in vivo models of obesity as well as human breast tissue have contributed to our understanding of how obesity alters mammary tissue. Localized changes in mammary epithelial cell populations, elevated secretion of adipokines and angiogenic mediators, inflammation within mammary adipose tissue, and remodeling of the extracellular matrix may result in an environment conducive to breast cancer growth. Despite these significant alterations caused by obesity within breast tissue, studies have suggested that some, but not all, obesity-induced changes may be mitigated with weight loss. Here, we review our current understanding regarding the impact of obesity on the breast microenvironment, how obesity-induced changes may contribute to breast tumor progression, and the impact of weight loss on the breast microenvironment.

The Role of Autophagy in White Adipose Tissue Function: Implications for Metabolic Health

White adipose tissue (WAT) is a highly adaptive endocrine organ that continuously remodels in response to nutritional cues. WAT expands to store excess energy by increasing adipocyte number and/or size. Failure in WAT expansion has serious consequences on metabolic health resulting in altered lipid, glucose, and inflammatory profiles. Besides an impaired adipogenesis, fibrosis and low-grade inflammation also characterize dysfunctional WAT. Nevertheless, the precise mechanisms leading to impaired WAT expansibility are yet unresolved. Autophagy is a conserved and essential process for cellular homeostasis, which constitutively allows the recycling of damaged or long-lived proteins and organelles, but is also highly induced under stress conditions to provide nutrients and remove pathogens. By modulating protein and organelle content, autophagy is also essential for cell remodeling, maintenance, and survival. In this line, autophagy has been involved in many processes affected during WAT maladaptation, including adipogenesis, adipocyte, and macrophage function, inflammatory response, and fibrosis. WAT autophagy dysregulation is related to obesity and diabetes. However, it remains unclear whether WAT autophagy alteration in obese and diabetic patients are the cause or the consequence of WAT malfunction. In this review, current data regarding these issues are discussed, focusing on evidence from human studies.

Adipose stem cells from patients with Crohn's disease show a distinctive DNA methylation pattern

Background

Crohn’s disease (CD) is characterized by persistent inflammation and ulceration of the small or large bowel, and expansion of mesenteric adipose tissue, termed creeping fat (CF). We previously demonstrated that human adipose-derived stem cells (hASCs) from CF of patients with CD exhibit dysfunctional phenotypes, including a pro-inflammatory profile, high phagocytic capacity, and weak immunosuppressive properties. Importantly, these phenotypes persist in patients in remission and are found in all adipose depots explored including subcutaneous fat. We hypothesized that changes in hASCs are a consequence of epigenetic modifications.

Methods

We applied epigenome-wide profiling with a methylation array (Illumina EPIC/850k array) and gene expression analysis to explore the impact of CD on the methylation signature of hASCs isolated from the subcutaneous fat of patients with CD and healthy controls (n = 7 and 5, respectively; cohort I). Differentially methylated positions (p value cutoff < 1 × 10⁻⁴ and ten or more DMPs per gene) and regions (inclusion threshold 0.2, p value cutoff < 1 × 10⁻² and more than 2 DMRs per gene) were identified using dmpfinder and Bumphunter (minfi), respectively. Changes in the expression of differentially methylated genes in hASCs were validated in a second cohort (n = 10/10 inactive and active CD and 10 controls; including patients from cohort I) and also in peripheral blood mononuclear cells (PBMCs) of patients with active/inactive CD and of healthy controls (cohort III; n = 30 independent subjects).

Results

We found a distinct DNA methylation landscape in hASCs from patients with CD, leading to changes in the expression of differentially methylated genes involved in immune response, metabolic, cell differentiation, and development processes. Notably, the expression of several of these genes in hASCs and PBMCs such as tumor necrosis factor alpha (TNFA) and PR domain zinc finger protein 16 (PRDM16) were not restored to normal (healthy) levels after disease remission.

Conclusions

hASCs of patients with CD exhibit a unique DNA methylation and gene expression profile, but the expression of several genes are only partially restored in patients with inactive CD, both in hASCs and PBMCs. Understanding how CD shapes the functionality of hASCs is critical for investigating the complex pathophysiology of this disease, as well as for the success of cell-based therapies.

Graphical abstract

Human adipose-stem cells isolated from subcutaneous fat of patients with Crohn’s disease exhibit an altered DNA methylation pattern and gene expression profile compared with those isolated from healthy individuals, with immune system, cell differentiation, metabolic and development processes identified as the main pathways affected. Interestingly, the gene expression of several genes involved in these pathways is only partially restored to control levels in patients with inactive Crohn’s disease, both in human adipose-stem cells and peripheral blood mononuclear cells. Understanding how Crohn’s disease shapes the functionality of human adipose-stem cells is critical for investigating the complex pathophysiology of this disease, as well as for the success of cell-based therapies.

Oxidized LDL Modify the Human Adipocyte Phenotype to an Insulin Resistant, Proinflamatory and Proapoptotic Profile

Little information exists in humans on the regulation that oxidized low-density lipoprotein (oxLDL) exerts on adipocyte metabolism, which is associated with obesity and type 2 diabetes. The aim was to analyze the oxLDL effects on adipocytokine secretion and scavenger receptors (SRs) and cell death markers in human visceral adipocytes. Human differentiated adipocytes from visceral adipose tissue from non-obese and morbidly obese subjects were incubated with increasing oxLDL concentrations. mRNA expression of SRs, markers of apoptosis and autophagy, secretion of adipocytokines, and glucose uptake were analyzed. In non-obese and in morbidly obese subjects, oxLDL produced a decrease in insulin-induced glucose uptake, a significant dose-dependent increase in tumor necrosis factor-α (TNF-α), IL-6, and adiponectin secretion, and a decrease in leptin secretion. OxLDL produced a significant increase of Lox-1 and a decrease in Cxcl16 and Cl-p1 expression. The expression of Bnip3 (marker of apoptosis, necrosis and autophagy) was significantly increased and Bcl2 (antiapoptotic marker) was decreased. OxLDL could sensitize adipocytes to a lower insulin-induced glucose uptake, a more proinflammatory phenotype, and could modify the gene expression involved in apoptosis, autophagy, necrosis, and mitophagy. OxLDL can upregulate Lox-1, and this could lead to a possible amplification of proinflammatory and proapoptotic effects of oxLDL.

The Effects of Facial Lipografting on Skin Quality: A Systematic Review

BACKGROUND

Autologous lipografting for improvement of facial skin quality was first described by Coleman in 2006. The current dogma dictates that adipose tissue-derived stromal cells that reside in the stromal vascular fraction of lipograft contribute to skin rejuvenation (e.g., increased skin elasticity), a more homogenous skin color, and softening of skin texture. Nowadays, many studies have been reported on this "skin rejuvenation" effect of autologous fat grafting. This systematic review was undertaken to assess the efficacy of autologous lipografting on skin quality.

METHODS

The MEDLINE, Embase, Cochrane Central, Web of Science, and Google Scholar databases were searched for studies evaluating the effect of autologous lipografting on facial skin quality (May 11, 2018). Outcomes of interest were skin texture, color, and elasticity in addition to histologic outcomes and number of complications.

RESULTS

Nine studies were included, with 301 patients treated in total. No meta-analysis could be performed because of heterogeneity of the metrics and outcomes. Eight studies reported increased skin elasticity; improvement in skin texture; and a more homogeneous skin color after treatment with lipografting, cellular stromal vascular fraction, or nanofat. One study reported no increased skin elasticity after lipografting. Histologic improvement was seen after lipografting and adipose tissue-derived stromal cell injections. However, in general, the level of evidence of the included studies was low. No serious complications were reported.

CONCLUSION

Autologous facial lipografting and cellular stromal vascular fraction and adipose tissue-derived stromal cell injections hardly seem to improve facial skin quality but can be considered a safe procedure.

Profile of Adipose-Derived Stem Cells in Obese and Lean Environments

BACKGROUND

With the demand for stem cells in regenerative medicine, new methods of isolating stem cells are highly sought. Adipose tissue is a readily available and non-controversial source of multipotent stem cells that carries a low risk for potential donors. However, elevated donor body mass index has been associated with an altered cellular microenvironment and thus has implications for stem cell efficacy in recipients. This review explored the literature on adipose-derived stem cells (ASCs) and the effect of donor obesity on cellular function.

METHODS

A review of published articles on obesity and ASCs was conducted with the PubMed database and the following search terms: obesity, overweight, adipose-derived stem cells and ASCs. Two investigators screened and reviewed the relevant abstracts.

RESULTS

There is agreement on reduced ASC function in response to obesity in terms of angiogenic differentiation, proliferation, migration, viability, and an altered and inflammatory transcriptome. Osteogenic differentiation and cell yield do not show reasonable agreement. Weight loss partially rescues some of the aforementioned features.

CONCLUSIONS

Generally, obesity reduces ASC qualities and may have an effect on the therapeutic value of ASCs. Because weight loss and some biomolecules have been shown to rescue these qualities, further research should be conducted on methods to return obese-derived ASCs to baseline.

LEVEL V

This journal requires that authors assign a level of evidence to each article. 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.

DNA methylation profile of different clones of human adipose stem cells does not allow to predict their differentiation potential

Human adipose stem cells can differentiate into various mesodermic lineages, including adipogenic, osteogenic, chondrogenic, myogenic and endothelial pathways. In addition, these cells types possess immunomodulatory properties, potentially useful for autoimmune and autoinflammatory diseases. However, single-cell expanded clones have shown that the cells can present a variety of differentiation potential, which may be partly due to epigenetic differences among them. The objective of this study was to assess if DNA methylation plays a role in the differentiation potential observed between different cell clones obtained from the same donor. To this end, the methylation profile of five clonal cell lines of human adipose stem cells obtained by liposuction from two donors was analyzed. Previous reports demonstrated that cell lines 1.7 and 1.22 from Donor 1 and 3.5 from Donor 3 were adipogenic-osteogenic, but not cell lines 1.10 and 3.10. The genes analyzed were neuronal, endothelial, myogenic, osteogenic, adipogenic, extracellular matrix, cell cycle, cytoskeleton and metabolic enzymes. All clones analyzed in this study displayed a similar pattern of methylation in most of the gene families: 85.5% were hypomethylated genes and 14.5% hypermethylated. In conclusion, the methylation pattern of the 1113 genes studied in this report was not a consistent tool to identify the differentiation potential of human adipose stem cells.

[Analysis of Biological Properties of Human Adult Mesenchymal Stem Cells and Their Effect on Mouse Hind Limb Ischemia]

BACKGROUND

Due to their self-renewal, proliferation, differentiation, and angiogenesis-inducing capacity, human adipose mesenchymal stem cells (AMSC) have potential clinical applications in the treatment of limb ischemia. AMSC from healthy donors have been shown to induce neovascularization in animal models. However, when cells were obtained from donors suffering from any pathology, their autologous application showed limited effectiveness. We studied whether liposuction niche and obesity could determine the regenerative properties of cells meaning that not all cell batches are suitable for clinical practice.

METHODS

AMSC obtained from 10 donors, obese and healthy, were expanded in vitro following a good manufacturing practice-like production protocol. Cell viability, proliferation kinetics, morphological analysis, phenotype characterization, and stemness potency were assessed over the course of the expansion process. AMSC selected for having the most suitable biological properties were used as an experimental treatment in a preclinical mouse model of hind limb ischemia.

RESULT

All cell batches were positively characterized as mesenchymal stem cells, but not all of them showed the same properties or were successfully expanded in vitro, depending on the characteristics of the donor and the extraction area. Notably, AMSC from the abdomen of obese donors showed undesirable biological properties. AMSC with low duplication times and multilineage differentiation potential and forming large densely packed colonies, were able, following expansion in vitro, to increase neovascularization and repair when implanted in the ischemic tissue of mice.

CONCLUSION

An extensive AMSC biological properties study could be useful to predict the potential clinical efficacy of cells before in vivo transplantation. Thus, peripheral ischemia and possibly other pathologies could benefit from stem cell treatments as shown in our preclinical model in terms of tissue damage repair and regeneration after ischemic injury.

Nature vs. Nurture: Defining the Effects of Mesenchymal Stromal Cell Isolation and Culture Conditions on Resiliency to Palmitate Challenge

As MSC products move from early development to clinical translation, culture conditions shift from xeno- to xeno-free systems. However, the impact of isolation and culture-expansion methods on the long-term resiliency of MSCs within challenging transplant environments is not fully understood. Recent work in our lab has shown that palmitate, a saturated fatty acid elevated in the serum of patients with obesity, causes MSCs to convert from an immunosuppressive to an immunostimulatory state at moderate to high physiological levels. This demonstrated that metabolically-diseased environments, like obesity, alter the immunomodulatory efficacy of healthy donor MSCs. In addition, it highlighted the need to test MSC efficacy not only in ideal conditions, but within challenging metabolic environments. To determine how the choice of xeno- vs. xeno-free media during isolation and expansion would affect future immunosuppressive function, umbilical cord explants from seven donors were subdivided and cultured within xeno- (fetal bovine serum, FBS) or xeno-free (human platelet lysate, PLT) medias, creating 14 distinct MSC preparations. After isolation and primary expansion, umbilical cord MSCs (ucMSC) were evaluated according to the ISCT minimal criteria for MSCs. Following baseline characterization, ucMSC were exposed to physiological doses of palmitate and analyzed for metabolic health, apoptotic induction, and immunomodulatory potency in co-cultures with stimulated human peripheral blood mononuclear cells. The paired experimental design (each ucMSC donor grown in two distinct culture environments) allowed us to delineate the contribution of inherent (nature) vs. environmentally-driven (nurture) donor characteristics to the phenotypic response of ucMSC during palmitate exposure. Culturing MSCs in PLT-media led to more consistent growth characteristics during the isolation and expansion for all donors, resulting in faster doubling times and higher cell yields compared to FBS. Upon palmitate challenge, PLT-ucMSCs showed a higher susceptibility to palmitate-induced metabolic disturbance, but less susceptibility to palmitate-induced apoptosis. Most striking however, was that the PLT-ucMSCs resisted the conversion to an immunostimulatory phenotype better than their FBS counterparts. Interestingly, examining MSC suppression of PBMC proliferation at physiologic doses of palmitate magnified the differences between donors, highlighting the utility of evaluating MSC products in stress-based assays that reflect the challenges MSCs may encounter post-transplantation.

Immunometabolism and Pulmonary Infections: Implications for Protective Immune Responses and Host-Directed Therapies

The biology and clinical efficacy of immune cells from patients with infectious diseases or cancer are associated with metabolic programming. Host immune- and stromal-cell genetic and epigenetic signatures in response to the invading pathogen shape disease pathophysiology and disease outcomes. Directly linked to the immunometabolic axis is the role of the host microbiome, which is also discussed here in the context of productive immune responses to lung infections. We also present host-directed therapies (HDT) as a clinically viable strategy to refocus dysregulated immunometabolism in patients with infectious diseases, which requires validation in early phase clinical trials as adjuncts to conventional antimicrobial therapy. These efforts are expected to be continuously supported by newly generated basic and translational research data to gain a better understanding of disease pathology while devising new molecularly defined platforms and therapeutic options to improve the treatment of patients with pulmonary infections, particularly in relation to multidrug-resistant pathogens.

Adipocyte alterations in endometriosis: reduced numbers of stem cells and microRNA induced alterations in adipocyte metabolic gene expression

BACKGROUND

Endometriosis is an estrogen dependent, inflammatory disorder occurring in 5-10% of reproductive-aged women. Women with endometriosis have a lower body mass index (BMI) and decreased body fat compared to those without the disease, yet few studies have focused on the metabolic abnormalities in adipose tissue in women with endometriosis. Previously, we identified microRNAs that are differentially expressed in endometriosis and altered in the serum of women with the disease. Here we explore the effect of endometriosis on fat tissue and identified a role for endometriosis-related microRNAs in fat metabolism and a reduction in adipocyte stem cell number.

METHODS

Primary adipocyte cells cultured from 20 patients with and without endometriosis were transfected with mimics and inhibitors of microRNAs 342-3p or Let 7b-5p to model the status of these microRNAs in endometriosis. RNA was extracted for gene expression analysis by qRT-PCR. PCNA expression was used as a marker of adipocyte proliferation. Endometriosis was induced experimentally in 9-week old female C57BL/6 mice and after 10 months fat tissue was harvested from both the subcutaneous (inguinal) and visceral (mesenteric) tissue. Adipose-derived mesenchymal stem cells in fat tissue were characterized in both endometriosis and non-endometriosis mice by FACS analysis.

RESULTS

Gene expression analysis showed that endometriosis altered the expression of Cebpa, Cebpb, Ppar-γ, leptin, adiponectin, IL-6, and HSL, which are involved in driving brown adipocyte differentiation, appetite, insulin sensitivity and fat metabolism. Each gene was regulated by an alteration in microRNA expression known to occur in endometriosis. Analysis of the stem cell content of adipose tissue in a mouse model of endometriosis demonstrated a reduced number of adipocyte stem cells.

CONCLUSIONS

We demonstrate that microRNAs Let-7b and miR-342-3p affected metabolic gene expression significantly in adipocytes of women with endometriosis. Similarly, there is a reduction in the adipose stem cell population in a mouse model of endometriosis. Taken together these data suggest that endometriosis alters BMI in part through an effect on adipocytes and fat metabolism.

Challenges and Controversies in Human Mesenchymal Stem Cell Therapy

Stem cell therapy is being intensely investigated within the last years. Expectations are high regarding mesenchymal stem cell (MSC) treatment in translational medicine. However, many aspects concerning MSC therapy should be profoundly defined. Due to a variety of approaches that are investigated, potential effects of stem cell therapy are not transparent. On the other hand, most results of MSC administration in vivo have confirmed their safety and showed promising beneficial outcomes. However, the therapeutic effects of MSC-based treatment are still not spectacular and there is a potential risk related to MSC applications into specific cell niche that should be considered in long-term observations and follow-up outcomes. In this review, we intend to address some problems and critically discuss the complex nature of MSCs in the context of their effective and safe applications in regenerative medicine in different diseases including graft versus host disease (GvHD) and cardiac, neurological, and orthopedic disorders.

Maternal pre-pregnancy obesity, offspring cord blood DNA methylation, and offspring cardiometabolic health in early childhood: an epigenome-wide association study

Pre-pregnancy obesity is an established risk factor for adverse sex-specific cardiometabolic health in offspring. Epigenetic alterations, such as in DNA methylation (DNAm), are a hypothesized link; however, sex-specific epigenomic targets remain unclear. Leveraging data from the Newborn Epigenetics Study (NEST) cohort, linear regression models were used to identify CpG sites in cord blood leukocytes associated with pre-pregnancy obesity in 187 mother-female and 173 mother-male offsprings. DNAm in cord blood was measured using the Illumina HumanMethylation450k BeadChip. Replication analysis was conducted among the Avon Longitudinal Study of Parents and Children (ALSPAC) cohort. Associations between pre-pregnancy obesity-associated CpG sites and offspring BMI z-score (BMIz) and blood pressure (BP) percentiles at 4-5-years of age were also examined. Maternal pre-pregnacy obesity was associated with 876 CpGs in female and 293 CpGs in male offspring (false discovery rate <5%). Among female offspring, 57 CpG sites, including the top 18, mapped to the TAPBP gene (range of effect estimates: -0.83% decrease to 4.02% increase in methylation). CpG methylation differences in the TAPBP gene were also observed among males (range of effect estimates: -0.30% decrease to 2.59% increase in methylation). While technically validated, none of the TAPBP CpG sites were replicated in ALSPAC. In NEST, methylation differences at CpG sites of the TAPBP gene were associated with BMI z-score (cg23922433 and cg17621507) and systolic BP percentile (cg06230948) in female and systolic (cg06230948) and diastolic (cg03780271) BP percentile in male offspring. Together, these findings suggest sex-specific effects, which, if causal, may explain observed sex-specific effects of maternal obesity.

Systemic Factors During Metabolic Disease Progression Contribute to the Functional Decline of Adipose Tissue-Derived Mesenchymal Stem Cells in Reproductive Aged Females

It is known that advanced metabolic disorders such as type 2 diabetes compromise the functional and regenerative capacity of endogenous adipose-tissue resident stem cells (ADSCs). It is, however, still unclear at which stage of disease progression ADSCs become compromised and whether systemic factors contribute to their functional decline. It was therefore hypothesized that inflammatory changes in the systemic microenvironment during distinct stages of disease progression negatively affect the functional capacity of ADSCs. A total of forty-seven (n = 47) black African reproductive aged females (32 ± 8 years; mean ± SD) were included in this study and subdivided into: (a) healthy lean (C; body mass index, BMI ≤ 25 kg/m²), (b) healthy overweight/obese (OB; BMI ≥ 25 kg/m²), (c) obese metabolic syndrome (MetS; BMI ≥ 30 kg/m²), and (d) type 2 diabetes mellitus (T2DM; previously diagnosed and on treatment) groups. Participants underwent anthropometric assessments and a DXA scan to determine their body composition and adipose indices. Each persons’ systemic metabolic- (cholesterol, HDL, LDL, triglycerides, and blood glucose) and inflammatory profiles (CRP, SDF1α, TNFα, IL6, IL8, IL10, and IFNy) were also evaluated. Participant-derived serum was then used to treat an ADSC cell line in vitro and its effect on viability (MTT-based assay), proliferation (BrdU), migration (wound healing assay), and osteogenic differentiation assessed. When exposed to serum derived from overweight/obese individuals (with or without metabolic syndrome), both the proliferative and migratory responses of ADSCs were less pronounced than when exposed to healthy control serum. Serum IL6 concentrations were identified as a factor influencing the proliferation of ADSCs, suggesting that long-term disruption to the systemic cytokine balance can potentially disrupt the proliferative responses of ADSCs. Obese participant-derived serum (with and without metabolic syndrome) furthermore resulted in lipid accumulation during osteogenic differentiation. This study, therefore demonstrated that systemic factors in obese individuals, regardless of the presence of metabolic syndrome, can be detrimental to the multifunctional properties of ADSCs.

Neonatal overfeeding impairs differentiation potential of mice subcutaneous adipose mesenchymal stem cells

Nutritional changes in the development (intrauterine life and postnatal period) may trigger long-term pathophysiological complications such as obesity and cardiovascular disease. Metabolic programming leads to organs and tissues modifications, including adipose tissue, with increased lipogenesis, production of inflammatory cytokines, and decreased glucose uptake. However, stem cells participation in adipose tissue dysfunctions triggered by overfeeding during lactation has not been elucidated. Therefore, this study was the first to evaluate the effect of metabolic programming on adipose mesenchymal stem cells (ASC) from mice submitted to overfeeding during lactation, using the litter reduction model. Cells were evaluated for proliferation capacity, viability, immunophenotyping, and reactive oxygen species (ROS) production. The content of UCP-2 and PGC1-α was determined by Western Blot. ASC differentiation potential in adipogenic and osteogenic environments was also evaluated, as well the markers of adipogenic differentiation (PPAR-γ and FAB4) and osteogenic differentiation (osteocalcin) by RT-qPCR. Results indicated that neonatal overfeeding does not affect ASC proliferation, ROS production, and viability. However, differentiation potential and proteins related to metabolism were altered. ASC from overfed group presented increased adipogenic differentiation, decreased osteogenic differentiation, and also showed increased PGC1-α protein content and reduced UCP-2 expression. Thus, ASC may be involved with the increased adiposity observed in neonatal overfeeding, and its therapeutic potential may be affected.

Obesity-Activated Adipose-Derived Stromal Cells Promote Breast Cancer Growth and Invasion

Obese women diagnosed with breast cancer have an increased risk for metastasis, and the underlying mechanisms are not well established. Within the mammary gland, adipose-derived stromal cells (ASCs) are heterogeneous cells with the capacity to differentiate into multiple mesenchymal lineages. To study the effects of obesity on ASCs, mice were fed a control diet (CD) or high-fat diet (HFD) to induce obesity, and ASCs were isolated from the mammary glands of lean and obese mice. We observed that obesity increased ASCs proliferation, decreased differentiation potential, and upregulated expression of α-smooth muscle actin, a marker of activated fibroblasts, compared to ASCs from lean mice. To determine how ASCs from obese mice impacted tumor growth, we mixed ASCs isolated from CD- or HFD-fed mice with mammary tumor cells and injected them into the mammary glands of lean mice. Tumor cells mixed with ASCs from obese mice grew significantly larger tumors and had increased invasion into surrounding adipose tissue than tumor cells mixed with control ASCs. ASCs from obese mice demonstrated enhanced tumor cell invasion in culture, a phenotype associated with increased expression of insulin-like growth factor-1 (IGF-1) and abrogated by IGF-1 neutralizing antibodies. Weight loss induced in obese mice significantly decreased expression of IGF-1 from ASCs and reduced the ability of the ASCs to induce an invasive phenotype. Together, these results suggest that obesity enhances local invasion of breast cancer cells through increased expression of IGF-1 by mammary ASCs, and weight loss may reverse this tumor-promoting phenotype.

Adipose tissue mitochondrial dysfunction in human obesity is linked to a specific DNA methylation signature in adipose-derived stem cells

Background

A functional population of adipocyte precursors, termed adipose-derived stromal/stem cells (ASCs), is crucial for proper adipose tissue (AT) expansion, lipid handling, and prevention of lipotoxicity in response to chronic positive energy balance. We previously showed that obese human subjects contain a dysfunctional pool of ASCs. Elucidation of the mechanisms underlying abnormal ASC function might lead to therapeutic interventions for prevention of lipotoxicity by improving the adipogenic capacity of ASCs.

Methods

Using epigenome-wide association studies, we explored the impact of obesity on the methylation signature of human ASCs and their differentiated counterparts. Mitochondrial phenotyping of lean and obese ASCs was performed. TBX15 loss- and gain-of-function experiments were carried out and western blotting and electron microscopy studies of mitochondria were performed in white AT biopsies from lean and obese individuals.

Results

We found that DNA methylation in adipocyte precursors is significantly modified by the obese environment, and adipogenesis, inflammation, and immunosuppression were the most affected pathways. Also, we identified TBX15 as one of the most differentially hypomethylated genes in obese ASCs, and genetic experiments revealed that TBX15 is a regulator of mitochondrial mass in obese adipocytes. Accordingly, morphological analysis of AT from obese subjects showed an alteration of the mitochondrial network, with changes in mitochondrial shape and number.

Conclusions

We identified a DNA methylation signature in adipocyte precursors associated with obesity, which has a significant impact on the metabolic phenotype of mature adipocytes.

Inflammatory biomarker in adipose stem cells of women with endometrial cancer

AIM

To explore inflammatory biomarkers secreted by adipose stem cells (ASCs) in omental, retroperitoneal and subcutaneous adipose tissues of women with endometrial cancer.

PATIENTS & METHODS

ASCs were collected from 22 women, aged 35-83 years, undergoing hysterectomy for endometrial cancer. Angiopoietin-2, EGF, IL-8, leptin, VEGFA, VEGFC and VEFGD levels in the ASC-conditioned media were analyzed by Luminex.

RESULTS

We found a significant difference between the three depots for IL-8 (p < 0.0001), with the highest levels of IL-8 in the omental depot. VEGFA levels were highest in the retroperitoneal depot.

CONCLUSION

This is one of the first studies to explore biomarker expression in ASC-conditioned media in adipose tissue. ASC characteristics may be important to evaluate in relation to cancer risk.

Insight into the development of obesity: functional alterations of adipose-derived mesenchymal stem cells

Obesity is associated with a variety of disorders including cardiovascular diseases, diabetes mellitus and cancer. Obesity changes the composition and structure of adipose tissue, linked to pro-inflammatory environment, endocrine/metabolic dysfunction, insulin resistance and oxidative stress. Adipose-derived mesenchymal stem cells (ASCs) have multiple functions like cell renewal, spontaneous repair and homeostasis in adipose tissue. In this review article, we have summarized the recent data highlighting that ASCs in obesity are defective in various functionalities and properties including differentiation, angiogenesis, motility, multipotent state, metabolism and immunomodulation. Inflammatory milieu, hypoxia and abnormal metabolites in obese tissue are crucial for impairing the functions of ASCs. Further work is required to explore the precise molecular mechanisms underlying its alterations and impairments. Based on these data, we suggest that deregulated ASCs, possibly also other mesenchymal stem cells, are important in promoting the development of obesity. Restoration of ASCs/mesenchymal stem cells might be an additional strategy to combat obesity and its associated diseases.

Functional Outcome of Human Adipose Stem Cell Injections in Rat Anal Sphincter Acute Injury Model

Anal incontinence is a devastating condition that significantly reduces the quality of life. Our aim was to evaluate the effect of human adipose stem cell (hASC) injections in a rat model for anal sphincter injury, which is the main cause of anal incontinence in humans. Furthermore, we tested if the efficacy of hASCs could be improved by combining them with polyacrylamide hydrogel carrier, Bulkamid. Human ASCs derived from a female donor were culture expanded in DMEM/F12 supplemented with human platelet lysate. Female virgin Sprague‐Dawley rats were randomized into four groups (n = 14–15/group): hASCs in saline or Bulkamid (3 × 10⁵/60 μl) and saline or Bulkamid without cells. Anorectal manometry (ARM) was performed before anal sphincter injury, at two (n = 58) and at four weeks after (n = 33). Additionally, the anal sphincter tissue was examined by micro‐computed tomography (μCT) and the histological parameters were compared between the groups. The median resting and peak pressure during spontaneous contraction measured by ARM were significantly higher in hASC treatment groups compared with the control groups without hASCs. There was no statistical difference in functional results between the hASC‐carrier groups (saline vs. Bulkamid). No difference was detected in the sphincter muscle continuation between the groups in the histology and μCT analysis. More inflammation was discovered in the group receiving saline with hASC. The hASC injection therapy with both saline and Bulkamid is a promising nonsurgical treatment for acute anal sphincter injury. Traditional histology combined with the 3D μCT image data lends greater confidence in assessing muscle healing and continuity. Stem Cells Translational Medicine2018;7:295–304

Adipose-derived cellular therapies in solid organ and vascularized-composite allotransplantation

PURPOSE OF REVIEW

Controlling acute allograft rejection following vascularized composite allotransplantation requires strict adherence to courses of systemic immunosuppression. Discovering new methods to modulate the alloreactive immune response is essential for widespread application of vascularized composite allotransplantation. Here, we discuss how adipose-derived cellular therapies represent novel treatment options for immune modulation and tolerance induction in vascularized composite allotransplantation.

RECENT FINDINGS

Adipose-derived mesenchymal stromal cells are cultured from autologous or allogeneic adipose tissue and possess immunomodulatory qualities capable of prolonging allograft survival in animal models of vascularized composite allotransplantation. Similar immunosuppressive and immunomodulatory effects have been observed with noncultured adipose stromal-vascular-fraction-derived therapies, albeit publication of in-vivo stromal vascular fraction cell modulation in transplantation models is lacking. However, both stromal vascular fraction and adipose derived mesenchymal stem cell therapies have the potential to effectively modulate acute allograft rejection via recruitment and induction of regulatory immune cells.

SUMMARY

To date, most reports focus on adipose derived mesenchymal stem cells for immune modulation in transplantation despite their phenotypic plasticity and reliance upon culture expansion. Along with the capacity for immune modulation, the supplemental wound healing and vasculogenic properties of stromal vascular fraction, which are not shared by adipose derived mesenchymal stem cells, hint at the profound therapeutic impact stromal vascular fraction-derived treatments could have on controlling acute allograft rejection and tolerance induction in vascularized composite allotransplantation. Ongoing projects in the next few years will help design the best applications of these well tolerated and effective treatments that should reduce the risk/benefit ratio and allow more patients access to vascularized composite allotransplantation therapy.

[Research progress of the donor factors and experimental factors affecting adipogenic differentiation of adipose derived stem cells]

Objective

To summarize the donor factors and experimental factors that affect adipogenic differentiation of adipose derived stem cells, so as to provide reference for adipogenic differentiation of adipose derived stem cells.

Methods

The related research literature about donor factors and experimental factors affecting adipogenic differentiation of adipose derived stem cells in recent years was extensively reviewed and summarized.

Results

There are a lot of donor factors and experimental factors affecting adipogenic differentiation of adipose derived stem cells, but some of the factors are still controversial, such as donor age, health status, adipose tissue of different parts, and so on. These factors need to be further studied.

Conclusion

The donor factors and experimental factors that affect adipogenic differentiation of adipose derived stem cells should be deeply studied and the controversial issues should be clarified to lay a solid foundation for the application of adipose derived stem cells in adipose tissue engineering.

Crohn's Disease Disturbs the Immune Properties of Human Adipose-Derived Stem Cells Related to Inflammasome Activation

Crohn's disease (CD) is characterized by the expansion of mesenteric fat, also known as “creeping fat.” We explored the plasticity and immune properties of adipose-derived stem cells (ASCs) in the context of CD as potential key players in the development of creeping fat. Mesenteric CD-derived ASCs presented a more proliferative, inflammatory, invasive, and phagocytic phenotype than equivalent cells from healthy donors, irrespective of the clinical stage. Remarkably, ASCs from the subcutaneous depot of patients with CD also showed an activated immune response that was associated with a reduction in their immunosuppressive properties. The invasive phenotype of mesenteric CD ASCs was governed by an inflammasome-mediated inflammatory state since blocking inflammasome signaling, mainly the secretion of interleukin-1β, reversed this characteristic. Thus, CD alters the biological functions of ASCs as adipocyte precursors, but also their immune properties. Selection of ASCs with the best immunomodulatory properties is advocated for the success of cell-based therapies.

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ASCs isolated from CD patients are highly proliferative, invasive, and phagocytic

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Proliferative ASCs may be responsible for the development of creeping fat

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ASCs from CD patients have dampened immunosuppressive properties

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Selection of the best immunosuppressive ASCs for cell therapy is advocated

Oncostatin M and TNF-α Induce Alpha-1 Antitrypsin Production in Undifferentiated Adipose Stromal Cells

Alpha-1 antitrypsin (A1AT), a circulating acute-phase reactant antiprotease, is produced and secreted by cells of endodermal epithelial origin, primarily hepatocytes, and by immune cells. Deficiency of A1AT is associated with increased risk of excessive lung inflammation and injury, especially following chronic cigarette smoke (CS) exposure. Exogenous administration of mesenchymal progenitor cells, including adipose tissue-derived stromal/stem cells (ASC), alleviates CS-induced lung injury through paracrine effectors such as growth factors. It is unknown, however, if mesodermal ASC can secrete functional A1AT and if CS exposure affects their A1AT production. Human ASC collected via liposuction from nonsmoking or smoking donors were stimulated by inflammatory cytokines tumor necrosis alpha (TNFα), oncostatin M (OSM), and/or dexamethasone (DEX) or were exposed to sublethal concentrations of ambient air control or CS extract (0.5%-2%). We detected minimal expression and secretion of A1AT by cultured ASC during unstimulated conditions, which significantly increased following stimulation with TNFα or OSM. Furthermore, TNFα and OSM synergistically enhanced A1AT expression and secretion, which were further increased by DEX. The A1AT transcript variant produced by stimulated ASC resembled that produced by bronchial epithelial cells rather than the variant produced by monocytes/macrophages. While the cigarette smoking status of the ASC donor had no measurable effect on the ability of ASC to induce A1AT expression, active exposure to CS extract markedly reduced A1AT expression and secretion by cultured ASC, as well as human tracheobronchial epithelial cells. ASC-secreted A1AT covalently complexed with neutrophil elastase in control ASC, but not in cells transfected with A1AT siRNA. Undifferentiated ASC may require priming to secrete functional A1AT, a potent antiprotease that may be relevant to stem cell therapeutic effects.

Enhanced migration of murine fibroblast-like 3T3-L1 preadipocytes on type I collagen-coated dish is reversed by silibinin treatment

Migration of fibroblast-like preadipocytes is important for the development of adipose tissue, whereas excessive migration is often responsible for impaired adipose tissue related with obesity and fibrotic diseases. Type I collagen (collagen I) is the most abundant component of extracellular matrix and has been shown to regulate fibroblast migration in vitro, but its role in adipose tissue is not known. Silibinin is a bioactive natural flavonoid with antioxidant and antimetastasis activities. In this study, we found that type I collagen coating promoted the proliferation and migration of murine 3T3-L1 preadipocytes in a dose-dependent manner, implying that collagen I could be an extracellular signal. Regarding the mechanisms of collagen I-stimulated 3T3-L1 migration, we found that NF-κB p65 is activated, including the increased nuclear translocation of NF-κB p65 as well as the upregulation of NF-κB p65 phosphorylation and acetylation, accompanied by the increased expressions of proinflammatory factors and the generation of reactive oxygen species (ROS). Reduction of collagen I-enhanced migration of cells by treatment with silibinin was associated with suppression of NF-κB p65 activity and ROS generation, and negatively correlated with the increasing sirt1 expression. Taken together, the enhanced migration of 3T3-L1 cells induced on collagen I-coated dish is mediated by the activation of NF-κB p65 function and ROS generation that can be alleviated with silibinin by upregulation of sirt1, leading to the repression of NF-κB p65 function and ROS generation.

The Use of Adipose-Derived Stem Cells in Selected Skin Diseases (Vitiligo, Alopecia, and Nonhealing Wounds)

The promising results derived from the use of adipose-derived stem cells (ADSCs) in many diseases are a subject of observation in preclinical studies. ADSCs seem to be the ideal cell population for the use in regenerative medicine due to their easy isolation, nonimmunogenic properties, multipotential nature, possibilities for differentiation into various cell lines, and potential for angiogenesis. This article reviews the current data on the use of ADSCs in the treatment of vitiligo, various types of hair loss, and the healing of chronic wounds.

Comparison of intraoperative procedures for isolation of clinical grade stromal vascular fraction for regenerative purposes: a systematic review

Intraoperative application of the stromal vascular fraction (SVF) of adipose tissue requires a fast and efficient isolation procedure of adipose tissue. This review was performed to systematically assess and compare procedures currently used for the intraoperative isolation of cellular SVF (cSVF) and tissue SVF (tSVF) that still contain the extracellular matrix. Pubmed, EMBASE and the Cochrane central register of controlled trials databases were searched for studies that compare procedures for intraoperative isolation of SVF (searched 28 September 2016). Outcomes of interest were cell yield, viability of cells, composition of SVF, duration, cost and procedure characteristics. Procedures were subdivided into procedures resulting in a cSVF or tSVF. Thirteen out of 3038 studies, evaluating 18 intraoperative isolation procedures, were considered eligible. In general, cSVF and tSVF intraoperative isolation procedures had similar cell yield, cell viability and SVF composition compared to a nonintraoperative (i.e. culture laboratory-based collagenase protocol) control group within the same studies. The majority of intraoperative isolation procedures are less time consuming than nonintraoperative control groups, however. Intraoperative isolation procedures are less time-consuming than nonintraoperative control groups with similar cell yield, viability of cells and composition of SVF, and therefore more suitable for use in the clinic. Nevertheless, none of the intraoperative isolation procedures could be designated as the preferred procedure to isolate SVF. Copyright © 2017 John Wiley & Sons, Ltd.

Adipose stem cells from obese patients show specific differences in the metabolic regulators vitamin D and Gas5

Adipose tissue is a significant source of mesenchymal stem cells for regenerative therapies; however, caution should be taken as their environmental niche can affect their functional properties. We have previously demonstrated the negative impact of obesity on the function of adipose-derived stem cells (ASCs). Here we have evaluated other possible properties and targets that are altered by obesity such as the recently described long non-coding molecule Gas5, which is involved in glucocorticoid resistance. Using ASCs isolated from obese (oASCs) and control subjects (cASCs), we have analyzed additional metabolic and inflammatory conditions that could be related with their impaired therapeutic potential and consequently their possible usefulness in the clinic.

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Altered genetic and metabolic targets by obesity in adipose stem cells population

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Gas5 involved in glucocorticoid resistance such as altered target

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Additional metabolic and inflammation conditions on obese adipose stem cells

Survivin, a key player in cancer progression, increases in obesity and protects adipose tissue stem cells from apoptosis

Adipose tissue (AT) has a central role in obesity-related metabolic imbalance through the dysregulated production of cytokines and adipokines. In addition to its known risk for cardiovascular disease and diabetes, obesity is also a major risk for cancer. We investigated the impact of obesity for the expression of survivin, an antiapoptotic protein upregulated by adipokines and a diagnostic biomarker of tumor onset and recurrence. In a cross-sectional study of 111 subjects classified by body mass index, circulating levels of survivin and gene expression in subcutaneous AT were significantly higher in obese patients and positively correlated with leptin. Within AT, survivin was primarily detected in human adipocyte-derived stem cells (hASCs), the adipocyte precursors that determine AT expansion. Remarkably, survivin expression was significantly higher in hASCs isolated from obese patients that from lean controls and was increased by proinflammatory M1 macrophage soluble factors including IL-1β. Analysis of survivin expression in hASCs revealed a complex regulation including epigenetic modifications and protein stability. Surprisingly, obese hASCs showed survivin promoter hypermethylation that correlated with a significant decrease in its mRNA levels. Nonetheless, a lower level of mir-203, which inhibits survivin protein translation, and higher protein stability, was found in obese hASCs compared with their lean counterparts. We discovered that survivin levels determine the susceptibility of hASCs to apoptotic stimuli (including leptin and hypoxia). Accordingly, hASCs from an obese setting were protected from apoptosis. Collectively, these data shed new light on the molecular mechanisms governing AT expansion in obesity through promotion of hASCs that are resistant to apoptosis, and point to survivin as a potential new molecular player in the communication between AT and tumor cells. Thus, inhibition of apoptosis targeting survivin might represent an effective strategy for both obesity and cancer therapy.

Enhancement of individual differences in proliferation and differentiation potentials of aged human adipose-derived stem cells

Background

Adipose-derived stem cells (ASCs) are a robust, multipotent cell source. They are easily obtained and hold promise in many regenerative applications. It is generally considered that the function of somatic stem cells declines with age. Although several studies have examined the effects of donor age on proliferation potential and pluripotency of ASCs, the results of these studies were not consistent.

Objective

This study tested whether the donor age affects the yield of ASCs from adipose tissue, as well as the proliferation and differentiation potentials of ASCs.

Methods

This study used ASCs obtained from adipose tissues of 260 donors (ages 5–97 years). ASCs were examined for individual differences in proliferation, and adipogenic, osteogenic and chondrogenic differentiation potentials in vitro. Characteristics of ASCs from each donor were evaluated by the principal component analysis (PCA) using their potential parameters.

Results

Analyses on ASCs demonstrated that adipogenic potentials declined with age, but proliferation, osteogenic and chondrogenic potentials were not correlated with age. Interestingly, in all ASC potentials, including adipogenesis, individual differences were observed. Principal component analysis (PCA) revealed that individual differences became evident in the elderly, and those variations were more prominent in females than in males.

Conclusions

This study demonstrated age-related changes in the potentials of ASCs and revealed that the individual differences of ASCs become significant in people over 60 years of age (for females over 60, and for males over 80). We believe that it is important to carefully observe ASC potentials in order to achieve effective regenerative medicine treatments using ASCs.

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ASCs can be isolated from subjects in all ages.

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Adipogenic potential of ASCs declines with age.

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Chondrogenic and osteogenic potentials of ASCs are not affected by age.

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Proliferation and differentiation potentials of ASCs are individually different.

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Individual difference of ASC potentials becomes significant over 60 years of age.

A Glycovariant of Human CD44 is Characteristically Expressed on Human Mesenchymal Stem Cells

The clinical effectiveness of systemically administered human mesenchymal stem cells (hMSCs) depends on their capacity to engage vascular endothelium. hMSCs derived from bone marrow (BM-hMSCs) natively lack endothelial binding capacity, but express a CD44 glycovariant containing N-linked sialyllactosamines that can be α(1,3)-fucosylated using fucosyltransferase-VI (FTVI) to enforce sLe^X decorations, thereby creating hematopoietic cell E-/L-selectin ligand (HCELL). HCELL expression programs potent shear-resistant adhesion of circulating cells to endothelial beds expressing E-selectin. An alternative source of hMSCs is adipose tissue (A-hMSCs), and we assessed whether A-hMSCs bind E-selectin and/or possess sialyllactosamine-decorated CD44 accessible to α(1,3)-fucosylation. Similar to BM-hMSCs, we found that A-hMSCs natively lack E-selectin ligands, but FTVI-mediated cell surface α(1,3)-fucosylation induces sLe^X expression and robust E-selectin binding secondary to conversion of CD44 into HCELL. Moreover, treatment with the α(1,3)-fucosyltransferase-FTVII also generated expression of HCELL on both BM-hMSCs and A-hMSCs, with sLe^X decorations created on N-linked glycans of the "standard" CD44 (CD44s) isoform. The finding that hMSCs from both source tissues each lack native E-selectin ligand expression prompted examination of the expression of glycosyltransferases that direct lactosaminyl glycan synthesis. These studies reveal that both types of hMSCs conspicuously lack transcripts encoding α(1,3)-fucosyltransferases, but equally express glycosyltransferases critical to creation of sialyllactosamines. Collectively, these data indicate that assembly of a sialyllactosaminyl-decorated CD44s glycovariant is a conserved feature of hMSCs derived from adipose tissue and marrow, thus identifying a CD44 glycosignature of these cells and supporting the applicability of cell surface α(1,3)-fucosylation in programming migration of systemically administered A-hMSCs to sites of tissue injury/inflammation. Stem Cells 2017;35:1080-1092.

Current use of autologous adipose tissue-derived stromal vascular fraction cells for orthopedic applications

Autologous adipose stromal vascular fractions (SVFs) containing adipose tissue-derived stem cells (ASCs) are currently being used in clinical settings for various orthopedic applications for human patients. Due to its potential capability of regenerating cartilage, bone, and tendons, autologous adipose SVFs are being tried in treating patients with osteoarthritis (OA), chondromalacia, meniscus tear, osteonecrosis of the femoral head, and tendon injuries. Here, we have reviewed available human clinical studies with regard to patient applications of autologous adipose SVF containing ASCs, specifically assessing effectiveness and safety in the field of orthopedic disorders. All studies reviewed in this article presents potential benefits of autologous adipose SVF in various orthopedic applications without any serious side effects.

Signaling Interplay between Bone Marrow Adipose Tissue and Multiple Myeloma cells

In the year 2000, Hanahan and Weinberg (1) defined the six Hallmarks of Cancer as: self-sufficiency in growth signals, evasion of apoptosis, insensitivity to antigrowth mechanisms, tissue invasion and metastasis, limitless replicative potential, and sustained angiogenesis. Eleven years later, two new Hallmarks were added to the list (avoiding immune destruction and reprograming energy metabolism) and two new tumor characteristics (tumor-promoting inflammation and genome instability and mutation) (2). In multiple myeloma (MM), a destructive cancer of the plasma cell that grows predominantly in the bone marrow (BM), it is clear that all these hallmarks and characteristics are in play, contributing to tumor initiation, drug resistance, disease progression, and relapse. Bone marrow adipose tissue (BMAT) is a newly recognized contributor to MM oncogenesis and disease progression, potentially affecting MM cell metabolism, immune action, inflammation, and influences on angiogenesis. In this review, we discuss the confirmed and hypothetical contributions of BMAT to MM development and disease progression. BMAT has been understudied due to technical challenges and a previous lack of appreciation for the endocrine function of this tissue. In this review, we define the dynamic, responsive, metabolically active BM adipocyte. We then describe how BMAT influences MM in terms of: lipids/metabolism, hypoxia/angiogenesis, paracrine or endocrine signaling, and bone disease. We then discuss the connection between BMAT and systemic inflammation and potential treatments to inhibit the feedback loops between BM adipocytes and MM cells that support MM progression. We aim for researchers to use this review to guide and help prioritize their experiments to develop better treatments or a cure for cancers, such as MM, that associate with and may depend on BMAT.