Successful in vitro expansion and differentiation of cord blood derived CD34+ cells into early endothelial progenitor cells reveals highly differential gene expression.
Ahrens. Ingo I; Domeij. Helena H; Topcic. Denijal D; Haviv. Izhak I; Merivirta. Ruusu-Maaria RM; Agrotis. Alexander A; Leitner. Ephraem E; Jowett. Jeremy B JB; Bode. Christoph C; Lappas. Martha M; Peter. Karlheinz K
Key Findings
- A new culture method expands early EPCs about 48‑fold from cord blood.
- The expanded EPCs show typical surface markers (VEGFR‑2, CD144, CD18, CD61) and functional traits like LDL uptake and tube formation when paired with mature endothelial cells.
- Microarray data reveal LL‑37 (CAMP) as the top up‑regulated gene, together with PDK4, alpha‑2‑macroglobulin, GDF15 and galectin‑3.
Practical Outcomes
- For DIY health enthusiasts, the study highlights LL‑37 as a molecule that spikes when EPCs mature, hinting it might play a role in vascular repair. However, the work is purely in vitro and uses cord blood cells, so there’s no direct dosing or supplement protocol to apply. It may inspire further research into LL‑37‑based strategies for heart health, but currently it offers limited actionable steps.
Summary
Scientists figured out a way to grow a lot more early endothelial progenitor cells (EPCs) from umbilical cord blood in the lab. During this process the gene for the peptide LL‑37 (CAMP) became the most strongly increased, along with other genes linked to heart protection and new blood‑vessel growth.
Abstract
Endothelial progenitor cells (EPCs) can be purified from peripheral blood, bone marrow or cord blood and are typically defined by a limited number of cell surface markers and a few functional tests. A detailed in vitro characterization is often restricted by the low cell numbers of circulating EPCs. Therefore in vitro culturing and expansion methods are applied, which allow at least distinguishing two different types of EPCs, early and late EPCs. Herein, we describe an in vitro culture technique with the aim to generate high numbers of phenotypically, functionally and genetically defined early EPCs from human cord blood. Characterization of EPCs was done by flow cytometry, immunofluorescence microscopy, colony forming unit (CFU) assay and endothelial tube formation assay. There was an average 48-fold increase in EPC numbers. EPCs expressed VEGFR-2, CD144, CD18, and CD61, and were positive for acetylated LDL uptake and ulex lectin binding. The cells stimulated endothelial tube formation only in co-cultures with mature endothelial cells and formed CFUs. Microarray analysis revealed highly up-regulated genes, including LL-37 (CAMP), PDK4, and alpha-2-macroglobulin. In addition, genes known to be associated with cardioprotective (GDF15) or pro-angiogenic (galectin-3) properties were also significantly up-regulated after a 72 h differentiation period on fibronectin. We present a novel method that allows to generate high numbers of phenotypically, functionally and genetically characterized early EPCs. Furthermore, we identified several genes newly linked to EPC differentiation, among them LL-37 (CAMP) was the most up-regulated gene.
Study Information
pubmed
2011
2011-08-12T00:00:00.000Z
10.1371/journal.pone.0023210
55
57