Pulmonary thrombosis in the mouse following intravenous administration of quantum dot-labeled mesenchymal cells

Abstract

Quantum dots (QDs) are emerging as novel diagnostic agents. Yet, only a few studies have examined the possible deleterious effects of QD-labeled stem cells. We assessed the potential toxic effects of QD-labeled human embryonic palatal mesenchymal (QD-HEPM) cells in male NOD/SCID mice for six months, following the administration of a single intravenous injection. Control animals were administered with non-labeled HEPM cells. No treatment-related clinical signs, hematological, or biochemical parameters were found in the QD-HEPM animals in comparison to control animals. Histologically, multifocal organizing thrombi were noted in the pulmonary arteries of all QD-HEPM animals from the one-week study group and in one animal from the one-month group. Additionally, increased severity of perivascular inflammation was noted at the injection sites of QD-HEPM animals from the one-week group. This is the first study reporting histopathological evidence for pro-thrombotic adverse effects mediated by QD labeling.

Keywords::

• Pulmonary thrombosis
• quantum dots
• NOD/SCID mouse
• mesenchymal stem cells

Acknowledgments

The authors wish to thank Dr Yona Grunfeld from Harlan Biotech Ltd, Israel for the excellent comments. This research was supported [in part] by the Intramural Research Program of the NIH, National Institutes of Environmental Health Sciences and by Genesis Cell Therapy Consortium (A.R.), operated by the Chief Scientist Office of the Israeli Ministry of Industry, Trade and Labor (MIT).

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper and have no competing financial interests.