Article

Human breast microvascular endothelial cells retain phenotypic traits in long-term finite life span culture.

Faculty of Medicine, University of Iceland, Reykjavik, Iceland.
In Vitro Cellular & Developmental Biology - Animal (impact factor: 1.31). 42(10):332-40. DOI:10.1290/0602017.1 pp.332-40
Source: PubMed

ABSTRACT Attempts to study endothelial-epithelial interactions in the human breast have been hampered by lack of protocols for long-term cultivation of breast endothelial cells (BRENCs). The aim of this study was to establish long-term cultures of BRENCs and to compare their phenotypic traits with the tissue of origin. Microvasculature was localized in situ by immunohistochemistry in breast samples. From this tissue, collagen-rich stroma and adipose tissue were dissected mechanically and further disaggregated to release microvessel organoids. BRENCs were cultured from these organoids in endothelial specific medium and characterized by staining for endothelial markers. Microvessels were a prominent feature of intralobular tissue as evidenced by immunostaining against endothelial specific markers such as CD31, VE-cadherin, and von Willebrand factor (VWF). Double staining against VE-cadherin and lymphatic vessel endothelial hyaluronan receptor-1 (LYVE-1) showed that blood and lymphatic vessels could be distinguished. An antibody against CD31 was used to refine protocols for isolation of microvasculature from reduction mammoplasties. BRENCs retained critical traits even at high passage, including uptake of low-density lipoprotein, and had E-selectin induced upon treatment with tumor necrosis factor-alpha. The first signs of senescence in passage 14 were accompanied by gain of trisomy 11. At passage 18 cells showed chromosomal aberrations and growth arrest as revealed by beta-galactosidase staining. We demonstrate here that breast microvasculature may serve as a large-scale source for expansion of BRENCs with molecular and functional traits preserved. These cells will form the basis for studies on the role of endothelial cells in breast morphogenesis.

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Keywords

adipose tissue
 
breast endothelial cells
 
breast morphogenesis
 
chromosomal aberrations
 
critical traits
 
endothelial markers
 
endothelial specific markers
 
endothelial specific medium
 
first signs
 
functional traits
 
human breast
 
intralobular tissue
 
long-term cultivation
 
long-term cultures
 
phenotypic traits
 
reduction mammoplasties
 
release microvessel organoids
 
study endothelial-epithelial interactions
 
tumor necrosis factor-alpha
 
von Willebrand factor