uu.seUppsala University Publications
Change search
ReferencesLink to record
Permanent link

Direct link
Effects of Quantum Dot Labeling on Endothelial Progenitor Cell Function and Viability
Show others and affiliations
2010 (English)In: Cell MedicineArticle in journal (Refereed) Published
Abstract [en]

Endothelial progenitor cells (EPC) play an important role in repairing damaged endothelium. An effective imaging method for in vivo tracking of EPCs is essential for understanding EPC-based cell therapy. Fluorescent quantum dots (QDs) have attractive optical characteristics such as extreme brightness and photostability. QDs are currently being investigated as probes for stem cell labeling; however, there is concern about whether QDs can be used safely. We investigated whether quantum dot (QD) labeling would influence EPC viability and function. Rat bone marrow-derived EPCs were cultured and characterized. The cells were labeled with near-infrared-emitting, carboxyl-coated QDs (8 nM) for 24 h. QD labeling efficiency was higher than 97%. Using WST-1 assay, we showed that the viability of the QD-labeled EPCs was not different from that of the control EPCs. Moreover, QD labeling did not influence the ability of EPCs to form capillary tubes on Matrigel and to migrate. The percentage of QD-positive cells decreased with time, probably due to the rapid division of EPCs. These data suggest that the carboxyl-coated QD705 can be useful for labeling EPCs without interrupting their viability and functions.

Place, publisher, year, edition, pages
Keyword [en]
Endothelial progenitor cells, Quantum dots, Cell labeling, Migration, Capillary tube formation
National Category
Nano Technology Cell Biology Medical Engineering
URN: urn:nbn:se:uu:diva-182949DOI: 10.3727/215517910X451603OAI: oai:DiVA.org:uu-182949DiVA: diva2:561528
Available from: 2012-10-19 Created: 2012-10-19 Last updated: 2012-10-19
In thesis
1. Quantum dot biomarkers for tracking endothelial progenitor cells and activated endothelium
Open this publication in new window or tab >>Quantum dot biomarkers for tracking endothelial progenitor cells and activated endothelium
2011 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

The development of new visualization techniques is essential in the field of bioimaging to gain deeper knowledge about various medical and biological events at the cellular and molecular levels. Quantum dots (QDs) are semiconductor nanocrystals which are opening new perspectives in biotechnology due to their powerful optical properties and high stability.  Utilization of QDs instead of commonly used organic dyes in labeling techniques adds several advantages, such as longer signal observation time of the biological samples; convenient multicolor labeling; deep tissue and organ tracking. Furthermore, more information can be obtained about the environment where QDs are located by characterizing the optical behavior of the QDs.

In this thesis work carboxyl coated QDs were used to label endothelial progenitor cells (EPCs). EPCs play an important role in cardiovascular diseases and the repair of the damaged endothelium, therefore an efficient in vivo tracking method is essential to understand the therapeutic potential of these cells. Our findings show an effective, cytoplasmic labeling of EPCs. Cell viability assay shows that QDs are not toxic to the cells in the concentration and incubation time tested in the study and QDs does not change the cell functions.

Furthermore commercially available QDs were functionalized with VCAM-1 binding peptide (VCAM-1BP) to specifically detect activated endothelial cells and activated endothelial wall in the aorta. Endothelial wall of the arteries are activated with VCAM-1 in the early stages of atherosclerosis, therefore early detection of this chronic disease may be performed with VCAM-1BP functionalized QDs. We found that VCAM-1BP functionalized QDs were able to detect the activated endothelium specifically.

The optical behavior of the QDs in different conditions and bio-systems were also characterized. It was found that several circumstances like different coating ligands can modify the fluorescence of the QDs. We observed that QD fluorescence intensity changes with different concentrations of Na+ and K+. We also found that significant blue-shift in QD peak emission occurs when QDs are internalized by cells and when functionalized QDs interact with cell surface molecule.

This thesis work provides efficient labeling techniques for cells and tissues with QDs and important knowledge about the optical behavior of QDs in bio-systems. These results give further perspectives to the future application of QD biomarkers as tracking agent and optical sensors for the different environmental changes in bio-systems.

Place, publisher, year, edition, pages
Stockholm: KTH, 2011. 52 p.
, Trita-BIO-Report, ISSN 1654-2312
quantum dots, bioimaging, endothelium, adult stem cells, confocal microscopy
National Category
Medical Engineering Nano Technology Cell Biology Chemical Sciences
Research subject
Biology; Chemistry; Physics
urn:nbn:se:uu:diva-182952 (URN)978-91-7415-929-5 (ISBN)
Available from: 2012-10-19 Created: 2012-10-19 Last updated: 2012-10-19Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full text

Search in DiVA

By author/editor
Molnar, Matyas
Nano TechnologyCell BiologyMedical Engineering

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 174 hits
ReferencesLink to record
Permanent link

Direct link