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Ultrasound-Assisted Liposuction Does Not Compromise the Regenerative Potential of Adipose-Derived Stem Cells

Duscher, Dominik; Atashroo, David; Maan, Zeshaan N; Luan, Anna; Brett, Elizabeth A; Barrera, Janos; Khong, Sacha M; Zielins, Elizabeth R; Whittam, Alexander J; Hu, Michael S; Walmsley, Graham G; Pollhammer, Michael S; Schmidt, Manfred; Schilling, Arndt F; Machens, Hans-Gunther; Huemer, Georg M; Wan, Derrick C; Longaker, Michael T; Gurtner, Geoffrey C
: Human mesenchymal stem cells (MSCs) have recently become a focus of regenerative medicine, both for their multilineage differentiation capacity and their excretion of proregenerative cytokines. Adipose-derived mesenchymal stem cells (ASCs) are of particular interest because of their abundance in fat tissue and the ease of harvest via liposuction. However, little is known about the impact of different liposuction methods on the functionality of ASCs. Here we evaluate the regenerative abilities of ASCs harvested via a third-generation ultrasound-assisted liposuction (UAL) device versus ASCs obtained via standard suction-assisted lipoaspiration (SAL). Lipoaspirates were sorted using fluorescent assisted cell sorting based on an established surface-marker profile (CD34+/CD31-/CD45-), to obtain viable ASCs. Yield and viability were compared and the differentiation capacities of the ASCs were assessed. Finally, the regenerative potential of ASCs was examined using an in vivo model of tissue regeneration. UAL- and SAL-derived samples demonstrated equivalent ASC yield and viability, and UAL ASCs were not impaired in their osteogenic, adipogenic, or chondrogenic differentiation capacity. Equally, quantitative real-time polymerase chain reaction showed comparable expression of most osteogenic, adipogenic, and key regenerative genes between both ASC groups. Cutaneous regeneration and neovascularization were significantly enhanced in mice treated with ASCs obtained by either UAL or SAL compared with controls, but there were no significant differences in healing between cell-therapy groups. We conclude that UAL is a successful method of obtaining fully functional ASCs for regenerative medicine purposes. Cells harvested with this alternative approach to liposuction are suitable for cell therapy and tissue engineering applications. SIGNIFICANCE: Adipose-derived mesenchymal stem cells (ASCs) are an appealing source of therapeutic progenitor cells because of their multipotency, diverse cytokine profile, and ease of harvest via liposuction. Alternative approaches to classical suction-assisted liposuction are gaining popularity; however, little evidence exists regarding the impact of different liposuction methods on the regenerative functionality of ASCs. Human ASC characteristics and regenerative capacity were assessed when harvested via ultrasound-assisted (UAL) versus standard suction-assisted liposuction. ASCs obtained via UAL were of equal quality when directly compared with the current gold standard harvest method. UAL is an adjunctive source of fully functional mesenchymal stem cells for applications in basic research and clinical therapy.
PMCID:4729547
PMID: 26702129
ISSN: 2157-6564
CID: 2032992

Adipose-Derived Stem Cell-Seeded Hydrogels Increase Endogenous Progenitor Cell Recruitment and Neovascularization in Wounds

Kosaraju, Revanth; Rennert, Robert C; Maan, Zeshaan N; Duscher, Dominik; Barrera, Janos; Whittam, Alexander J; Januszyk, Michael; Rajadas, Jayakumar; Rodrigues, Melanie; Gurtner, Geoffrey C
Adipose-derived mesenchymal stem cells (ASCs) are appealing for cell-based wound therapies because of their accessibility and ease of harvest, but their utility is limited by poor cell survival within the harsh wound microenvironment. In prior work, our laboratory has demonstrated that seeding ASCs within a soft pullulan-collagen hydrogel enhances ASC survival and improves wound healing. To more fully understand the mechanism of this therapy, we examined whether ASC-seeded hydrogels were able to modulate the recruitment and/or functionality of endogenous progenitor cells. Employing a parabiosis model and fluorescence-activated cell sorting analysis, we demonstrate that application of ASC-seeded hydrogels to wounds, when compared with injected ASCs or a noncell control, increased the recruitment of provascular circulating bone marrow-derived mesenchymal progenitor cells (BM-MPCs). BM-MPCs comprised 23.0% of recruited circulating progenitor cells in wounds treated with ASC-seeded hydrogels versus 8.4% and 2.1% in those treated with controls, p < 0.05. Exploring the potential for functional modulation of BM-MPCs, we demonstrate a statistically significant increase in BM-MPC migration, proliferation, and tubulization when exposed to hydrogel-seeded ASC-conditioned medium versus control ASC-conditioned medium (73.8% vs. 51.4% scratch assay closure; 9.1% vs. 1.4% proliferation rate; 10.2 vs. 5.5 tubules/HPF; p < 0.05 for all assays). BM-MPC expression of genes related to cell stemness and angiogenesis was also significantly increased following exposure to hydrogel-seeded ASC-conditioned medium (p < 0.05). These data suggest that ASC-seeded hydrogels improve both progenitor cell recruitment and functionality to effect greater neovascularization.
PMCID:4779321
PMID: 26871860
ISSN: 1937-335x
CID: 2033002

Platelet-Poor and Platelet-Rich Plasma Stimulate Bone Lineage Differentiation in Periodontal Ligament Stem Cells

Martinez, Constanza E; Gonzalez, Sergio A; Palma, Veronica; Smith, Patricio C
BACKGROUND: Plasma-derived fractions have been used as an autologous source of growth factors; however, limited knowledge concerning their biologic effects has hampered their clinical application. In this study, the authors analyze the content and specific effect of both platelet-rich plasma (PRP) and platelet-poor plasma (PPP) on osteoblastic differentiation using primary cultures of human periodontal ligament stem cells (HPLSCs). METHODS: The authors evaluated the growth factor content of PRP and PPP using a proteome profiler array and enzyme-linked immunosorbent assay. HPLSCs were characterized by flow cytometry and differentiation assays. The effect of PRP and PPP on HPLSC bone differentiation was analyzed by quantifying calcium deposition after 14 and 21 days of treatment. RESULTS: Albeit at different concentrations, the two fractions had similar profiles of growth factors, the most representative being platelet-derived growth factor (PDGF) isoforms (PDGF-AA, -BB, and -AB), insulin-like growth factor binding protein (IGFBP)-2, and IGFBP-6. Both formulations exerted a comparable stimulus on osteoblastic differentiation even at low doses (2.5%), increasing calcium deposits in HPLSCs. CONCLUSIONS: PRP and PPP showed a similar protein profile and exerted comparable effects on bone differentiation. Further studies are needed to characterize and compare the effects of PPP and PRP on bone healing in vivo.
PMID: 26367495
ISSN: 1943-3670
CID: 2559582

Skeletal muscle-specific eukaryotic translation initiation factor 2alpha phosphorylation controls amino acid metabolism and fibroblast growth factor 21-mediated non-cell-autonomous energy metabolism

Miyake, Masato; Nomura, Akitoshi; Ogura, Atsushi; Takehana, Kenji; Kitahara, Yoshihiro; Takahara, Kazuna; Tsugawa, Kazue; Miyamoto, Chinobu; Miura, Naoko; Sato, Ryosuke; Kurahashi, Kiyoe; Harding, Heather P; Oyadomari, Miho; Ron, David; Oyadomari, Seiichi
The eukaryotic translation initiation factor 2alpha (eIF2alpha) phosphorylation-dependent integrated stress response (ISR), a component of the unfolded protein response, has long been known to regulate intermediary metabolism, but the details are poorly worked out. We report that profiling of mRNAs of transgenic mice harboring a ligand-activated skeletal muscle-specific derivative of the eIF2alpha protein kinase R-like ER kinase revealed the expected up-regulation of genes involved in amino acid biosynthesis and transport but also uncovered the induced expression and secretion of a myokine, fibroblast growth factor 21 (FGF21), that stimulates energy consumption and prevents obesity. The link between the ISR and FGF21 expression was further reinforced by the identification of a small-molecule ISR activator that promoted Fgf21 expression in cell-based screens and by implication of the ISR-inducible activating transcription factor 4 in the process. Our findings establish that eIF2alpha phosphorylation regulates not only cell-autonomous proteostasis and amino acid metabolism, but also affects non-cell-autonomous metabolic regulation by induced expression of a potent myokine.-Miyake, M., Nomura, A., Ogura, A., Takehana, K., Kitahara, Y., Takahara, K., Tsugawa, K., Miyamoto, C., Miura, N., Sato, R., Kurahashi, K., Harding, H. P., Oyadomari, M., Ron, D., Oyadomari, S. Skeletal muscle-specific eukaryotic translation initiation factor 2alpha phosphorylation controls amino acid metabolism and fibroblast growth factor 21-mediated non-cell-autonomous energy metabolism.
PMCID:4945323
PMID: 26487695
ISSN: 1530-6860
CID: 2039072

The necrosome promotes pancreatic oncogenesis via CXCL1 and mincle-induced immune suppression [Meeting Abstract]

Werba, G; Seifert, L; Tiwari, S; Ly, N; Daley, D; Torres, Hernandez A; Barilla, R; Miller, G
Introduction: Disruption of apoptosis is a basic modality cancer cells exploit for survival. However, the role of programmed necrosis in the life cycle of pancreatic ductal adenocarcinoma (PDA) is uncertain. Here we report that the principal components of the necrosome, RIP1 and RIP3, are highly expressed in pancreatic ductal adenocarcinoma (PDA) and are further upregulated by chemotherapeutics. Methods: We evaluated the effects of deletion orblockade of the necroptosis pathway in pancreatic cancer on tumor size and survival, peritumoral fibroinflammation, and epithelial transformation. We utilized p48Cre;KrasG12D(KC) mice as our murine PDA oncogenesis model and crossed KC with RIP3-/- and Mincle-/- mice to create a knockout pancreatic cancer mouse model. Alternatively, we challenged wildtype mice with orthopic injection of the cancer cell line FC1242 into the pancreas. Components of the necroptosis pathway and the immune infiltrate within the pancreatic TME were assessed and characterized using immunohistochemistry, flow cytometry and western blotting in human and murine tissue. Results: Blockade of the necrosome in vitro promoted cancer cell proliferation and induced an aggressive oncogenic phenotype in transformed pancreatic epithelial cells. Conversely, in vivo RIP3 deletion or RIP1 inhibition was protective against oncogenic progression and was associated with the development of a highly immunogenic myeloid and T cell phenotype within the tumor microenvironment (TME). The immunesuppressive infiltrate associated with intact RIP1/RIP3 signaling was contingent on necroptosisinduced CXCL1 expression whereas CXCL1 blockade was protective against PDA. Moreover, we found that the necroptotic byproduct SAP130 was highly prevalent in PDA and Mincle - its cognate receptor - was upregulated in tumorinfiltrating myeloid cells. Mincle ligation powerfully promoted oncogenesis whereas Mincle deletion was protective against tumorigenesis and phenocopied the immunogenic reprogramming of the TME characteristic of RIP3 deletion. Conclusion: Our work describes a novel RIP1/RIP3-Mincle axis as a critical regulator of peritumoral immune suppression and PDA progression
EMBASE:72203707
ISSN: 1068-9265
CID: 2014822

Safety of Dalbavancin in the Treatment of Skin and Skin Structure Infections: A Pooled Analysis of Randomized, Comparative Studies

Dunne, Michael W; Talbot, George H; Boucher, Helen W; Wilcox, Mark; Puttagunta, Sailaja
INTRODUCTION: Dalbavancin is a new lipoglycopeptide that is active against Gram-positive pathogens, including methicillin-resistant Staphylococcus aureus. It has a half-life of 14.4 days, permitting intravenous treatment of acute bacterial skin and skin structure infections without the need for daily dosing. OBJECTIVE: The objective of these analyses was to compare the adverse event profile of dalbavancin with that of the comparator agents in the treatment of skin and skin structure infections. METHODS: Data on adverse events and laboratory assessments collected from 3002 patients enrolled in seven late-stage, randomized clinical trials were analyzed for patients receiving dalbavancin or a comparator antibiotic. RESULTS: Overall adverse event rates were similar or lower for patients receiving dalbavancin (799/1778; 44.9%) compared with those receiving comparator agents (573/1224; 46.8%, p = 0.012). The most common treatment-emergent adverse events were nausea, headache, diarrhea, constipation, vomiting, rash, urinary tract infection, pruritus, and insomnia. The duration and timing of the onset of adverse events were similar for patients receiving dalbavancin relative to the comparators. CONCLUSION: Dalbavancin exhibits a favorable overall safety profile for treatment of acute bacterial skin and skin structure infections due to Gram-positive bacteria.
PMCID:4735234
PMID: 26715497
ISSN: 0114-5916
CID: 2216462

Status of NCRP Scientific Committee 1-23 Commentary on Guidance on Radiation Dose Limits for the Lens of the Eye

Dauer, Lawrence T; Ainsbury, Elizabeth A; Dynlacht, Joseph; Hoel, David; Klein, Barbara E K; Mayer, Don; Prescott, Christina R; Thornton, Raymond H; Vano, Eliseo; Woloschak, Gayle E; Flannery, Cynthia M; Goldstein, Lee E; Hamada, Nobuyuki; Tran, Phung K; Grissom, Michael P; Blakely, Eleanor A
Previous National Council on Radiation Protection and Measurements (NCRP) publications have addressed the issues of risk and dose limitation in radiation protection and included guidance on specific organs and the lens of the eye. NCRP decided to prepare an updated commentary intended to enhance the previous recommendations provided in earlier reports. The NCRP Scientific Committee 1-23 (SC 1-23) is charged with preparing a commentary that will evaluate recent studies on the radiation dose response for the development of cataracts and also consider the type and severity of the cataracts as well as the dose rate; provide guidance on whether existing dose limits to the lens of the eye should be changed in the United States; and suggest research needs regarding radiation effects on and dose limits to the lens of the eye. A status of the ongoing work of SC 1-23 was presented at the Annual Meeting, "Changing Regulations and Radiation Guidance: What Does the Future Hold?" The following represents a synopsis of a few main points in the current draft commentary. It is likely that several changes will be forthcoming as SC 1-23 responds to subject matter expert review and develops a final document, expected by mid 2016.
PMCID:4697269
PMID: 26717175
ISSN: 1538-5159
CID: 4800222

A Critical Appraisal of Control Strategies for Soil-Transmitted Helminths

Campbell, Suzy J; Nery, Susana V; McCarthy, James S; Gray, Darren J; Soares Magalhaes, Ricardo J; Clements, Archie C A
Interventions that lead to reductions in soil-transmitted helminths (STHs) include chemotherapy with anthelmintic drugs and improvements in water, sanitation, and hygiene (WASH). In this opinion article we aim to determine the evidence for optimal approaches for STH control. First we explore the evidence for the above interventions. We then appraise two integration strategies: current chemotherapy-oriented integrated neglected tropical disease (NTD) control and expanded 'multicomponent integration', which includes integrated chemotherapy, WASH, and other intervention strategies. While multicomponent integrated control may be an effective approach to sustainably reduce STH transmission, there is a need for evidence to prove the feasibility of this approach.
PMID: 26795294
ISSN: 1471-5007
CID: 2104792

Emerging Roles of PCSK9: More Than a One-Trick Pony [Editorial]

Moore, Kathryn J; Goldberg, Ira J
PMCID:4732575
PMID: 26819460
ISSN: 1524-4636
CID: 1929182

Enrichment of Adipose-Derived Stromal Cells for BMPR1A Facilitates Enhanced Adipogenesis

Zielins, Elizabeth R; Paik, Kevin; Ransom, Ryan C; Brett, Elizabeth A; Blackshear, Charles P; Luan, Anna; Walmsley, Graham G; Atashroo, David A; Senarath-Yapa, Kshemendra; Momeni, Arash; Rennert, Robert; Sorkin, Michael; Seo, Eun Young; Chan, Charles K; Gurtner, Geoffrey C; Longaker, Michael T; Wan, Derrick C
BACKGROUND: Reconstruction of soft tissue defects has traditionally relied on the use of grafts and flaps, which may be associated with variable resorption and/or significant donor site morbidity. Cell-based strategies employing adipose-derived stromal cells (ASCs), found within the stromal vascular fraction (SVF) of adipose tissue, may offer an alternative strategy for soft tissue reconstruction. In this study, we investigated the potential of a bone morphogenetic protein receptor type 1A (BMPR1A)(+) subpopulation of ASCs to enhance de novo adipogenesis. METHODS: Human lipoaspirate was enzymatically digested to isolate SVF and magnetic-activated cell separation was utilized to obtain BMPR1A(+) and BMPR1A(-) cells. These cells, along with unenriched cells, were expanded in culture and evaluated for adipogenic gene expression and in vitro adipocyte formation. Cells from each group were also labeled with a green fluorescent protein (GFP) lentivirus and transplanted into the inguinal fat pads, an adipogenic niche, of immunocompromised mice to determine their potential for de novo adipogenesis. Confocal microscopy along with staining of lipid droplets and vasculature was performed to evaluate the formation of mature adipocytes by transplanted cells. RESULTS: In comparison to BMPR1A(-) and unenriched ASCs, BMPR1A(+) cells demonstrated significantly enhanced adipogenesis when cultured in an adipogenic differentiation medium, as evidenced by increased staining with Oil Red O and increased expression of peroxisome proliferator-activating receptor gamma (PPAR-gamma) and fatty acid-binding protein 4 (FABP4). BMPR1A(+) cells also formed significantly more adipocytes in vivo, as demonstrated by quantification of GFP+ adipocytes. Minimal formation of mature adipocytes was appreciated by BMPR1A(-) cells. CONCLUSIONS: BMPR1A(+) ASCs show an enhanced ability for adipogenesis in vitro, as shown by gene expression and histological staining. Furthermore, within an adipogenic niche, BMPR1A(+) cells possessed an increased capacity to generate de novo fat compared to BMPR1A(-) and unenriched cells. This suggests utility for the BMPR1A(+) subpopulation in cell-based strategies for soft tissue reconstruction.
PMCID:4779277
PMID: 26585335
ISSN: 1937-335x
CID: 2033012