Insulinlike growth factor action and production in adipocytes and endothelial cells from human adipose tissue

AbstractEndothelial cells are among the fundamental building blocks for vascular tissue engineering. However, a clinically viable source of endothelium has continued to elude the field. Here, we demonstrate the feasibility of sourcing autologous endothelium from human fat – an abundant and uniquely dispensable tissue that can be readily harvested with minimally invasive procedures. We investigate the challenges underlying the overgrowth of human adipose tissue-derived microvascular endothelial cells by stromal cells to facilitate the development of a reliable method for their acquisition. Magnet-assisted cell sorting strategies are established to mitigate the non-specific uptake of immunomagnetic microparticles, enabling the enrichment of endothelial cells to purities that prevent their overgrowth by stromal cells. This work delineates a reliable method for acquiring human adipose tissue-derived microvascular endothelial cells in large quantities with high purities that can be readily applied in future vascular tissue engineering applications.

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Abstract 1124: CD40L Induces Inflammation in Adipose Tissue - a Potential Link Between the Metabolic Syndrome and Atherosclerosis

Circulation ◽

10.1161/circ.116.suppl_16.ii_226-b ◽

2007 ◽

Vol 116 (suppl_16) ◽

Author(s):

Anna Missiou ◽

Isabel Platzer ◽

Sandra Ernst ◽

Uwe Schonbeck ◽

Peter Libby ◽

...

Keyword(s):

Metabolic Syndrome ◽

Endothelial Cells ◽

Adipose Tissue ◽

Cardiovascular Risk ◽

Inflammatory Cytokine ◽

Inflammatory Responses ◽

Human Adipose Tissue ◽

Cell Types ◽

High Cardiovascular Risk ◽

The Metabolic Syndrome

Background: CD40L figures prominently as marker and mediator of atherosclerosis and its clinical complications. Recent data also demonstrate an association between CD40L and the metabolic syndrome. In the light of these data we hypothesized a functional pro-inflammatory role of CD40L in adipose tissue that provokes systemic pro-inflammatory responses and potentially mediates some of the high cardiovascular risk associated with the metabolic syndrome. Methods and Results: Adipocytes and preadipocytes isolated from adipose tissue obtained from bariatic surgery did not express CD40L but its receptor CD40 as assessed by PCR and immunohistochemistry. Furthermore, sections of human adipose tissue from obese donors contained more macrophages and T cells colocalizing with CD40L than those from lean controls. Stimulation of both adipocytes and preadipocytes with recombinant CD40L resulted in a concentration- and time-dependent release of the pro-inflammatory cytokine IL-6, the chemokines MCP -1 and IL-8 as well as the inhibitor of fibrinolysis PAI-1 into the supernatant as quantified by ELISA. Membranes isolated from a Murine cell line overexpressing human CD40L reproduced these pro-inflammatory effects compared to respective controls. Interestingly, fenofibrate but neither rosiglitazone, metformin, nor atorvastatin attenuated the CD40L-inducible expression of these pro-atherogenic mediators. Finally, supernatants from adipocytes and preadipocytes stimulated with CD40L activated endothelial cells and macrophages, typical cell types resident in atherosclerotic lesions, as assessed by FACS for tissue factor, Mac-1, and ICAM-1, respectively. Conclusions: Our data suggest that CD40L induces inflammatory cytokine production in adipose tissue resulting in activation of endothelial cells and macrophages. This new mechanism may contribute to the high cardiovascular risk of patients suffering from the metabolic syndrome.

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CD45-CD34+ Endothelial Progenitor Cells (EPCs) from Human Adipose Tissue Promote Tumor Growth and Metastases

Blood ◽

10.1182/blood.v118.21.2208.2208 ◽

2011 ◽

Vol 118 (21) ◽

pp. 2208-2208

Author(s):

Patrizia Mancuso ◽

Ines Martin Padura ◽

Giuliana Gregato ◽

Paola Marighetti ◽

Angelica Calleri ◽

...

Keyword(s):

Breast Cancer ◽

Bone Marrow ◽

Endothelial Cells ◽

Adipose Tissue ◽

Breast Reconstruction ◽

Progenitor Cells ◽

Human Breast Cancer ◽

Human Adipose Tissue ◽

Human Breast ◽

Cd34 Cells

Abstract Abstract 2208 A catalytic role has been proposed in neoplastic angiogenesis and cancer progression for bone marrow-derived endothelial progenitor cells (EPCs). However, in preclinical and clinical studies the quantitative role of marrow-derived EPCs in cancer vascularization was found to be extremely variable. Adipose tissue represents an attractive source of autologous adult stem cells due to its abundance and surgical accessibility. Lipotransfer aspirates (LAs) from patients undergoing breast reconstruction after breast cancer surgery were analyzed by six colors flow cytometry and tissue culture. After collagenase digestion, cells were stained with the nuclear binding antigen Syto16 and 7-AAD and with CD34, CD45, CD133, CD31, CD140b, CD105, CD90, CD44, CD13, CD144, CD10, CD29, CD109, CD117, CD146,CD16, CD11c, CD14, CD38, CXCR4, VEGFR-1, VEGFR-2, VEGFR-3, Tie-2. The absolute count of CD45-CD34+ cells was obtained using reference beads in Trucount tubes (BD, Mountain View, CA). LAs were found to contain a large amount of CD45-CD34+ cells fulfilling the most recent criteria for EPC identification. These CD45-CD34+ cells included two subpopulations: CD45-CD34++ CD13+ CD140b+ CD44+ CD90++ cells and CD45-CD34+ CD31+CD105+ cells. We found in the adipose tissue about 263 fold more CD45-CD34+ EPCs/mL when compared to the bone marrow. In particular, the median of CD45-CD34+CD31- cells/mL was 181,046 (range 35,970–465,357), and the median of CD45-CD34+CD31+ cells/mL was 76,946 (range13,982-191,287). When compared to marrow-derived CD34+ cells, purified CD45-CD34+ adipose cells expressed similar levels of stemness-related genes such as NANOG, SOX2, Lin28 and significantly increased levels of angiogenesis-related genes such as CD144, VEGFR2, ALK-1. In vitro, CD45-CD34+ cells generated mature endothelial cells and capillary tubes as well as mature mesenchymal cells. When coinjected with triple negative human breast cancer MDA-MB-436 and HCC1937 cells in the mammary fat of a murine model of human breast cancer, purified CD45-CD34+ cells significantly increased tumor growth, and immunohistochemistry studies demonstrated the presence of human CD31+, CD34+, CD105+ endothelial cells lining the vessels of orthotopic breast cancers growing in mice co-injected with human adipose tissue-derived CD45-CD34+ cells. Moreover, in a mouse model of breast cancer metastatization we found an increased number of lung and axillary lymph node metastases when purified CD34+ WAT cells were injected into the third mammary fat pad after the primary tumor resection. In conclusion our data demonstrate that the phenotype of adipose derived EPCs is consistent with that reported for both bone marrow and circulating EPCs, but their frequency in adipose tissue is more than 250 fold higher. Further studies are ongoing to clarify what cell populations residing in the adipose tissue can be used safely for breast reconstruction and what are at risk for supporting the growth of otherwise quiescent cancer cells still resident after surgery. Disclosures: No relevant conflicts of interest to declare.

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