Engineered Tracking and Delivery of Mesenchymal Stem Cells (MSCs)

Mesenchymal stem cells (MSCs) are tissue culture plastic adherent cells that are able to differentiate into multiple cell types, modulate the immune system, and aid in wound repair. These versatile cells are thus being investigated to treat a wide variety of different diseases such as graft vs. host disease, rheumatoid arthritis, myocardial infarction, and damaged cartilage. In addition, with genetic modification, MSCs can be used as drug delivery vehicles to treat cancer or as a cell replacement therapy to treat osteogenesis imperfecta. However, the delivery of MSCs to a target organ, and the delivery of stem cells in general, remains a major challenge. This thesis investigates the hypothesis that when MSCs are efficiently delivered into the circulation, they will home to sites of injury. First, MSCs were genetically modified by lentiviral transduction with a dual reporter gene vector containing monomeric red fluorescent protein and luciferase in order to track the cells <i>in vivo</i> in real time. It was found that polybrene, an additive commonly used during transduction, severely inhibited MSC proliferation. A new method was developed for efficient lentiviral transduction using protamine sulfate, and other techniques. MSC engraftment to sites of injury was investigated by delivering cells into mice irradiated on one leg, with the non-irradiated leg serving as an internal negative control. Delivery of the cells into the aortic arch resulted in initial cell distribution throughout the entire body and engraftment in only the irradiated leg as detected by bioluminescent imaging (BLI). The biolumescence increased over time, indicating that the engrafted MSCs proliferated <i>in vivo</i>. In contrast, cells delivered intravenously were trapped in the lungs with no engraftment. This homing is specific to MSCs, since it was not observed with kidney cells. Furthermore, aortic arch delivery was efficient, as engraftment was consistently observed with a dose of only 2.5 x 10⁵ cells/mouse. Finally it was shown that MSCs are capable of being serially transplanted while maintaining their homing ability. Thus, this thesis demonstrates that MSCs can home and engraft at sites of injury from the circulation, that the homing is specific, and that the proper cell delivery method is critical for efficient cell engraftment. These results will aid in developing effective clinical MSC therapies.

Name thesis:degree_name

Doctor of Philosophy

Level thesis:degree_level

doctoral

Discipline thesis:degree_discipline

Biomedical Engineering

Grantor dc:publisher

Case Western Reserve University School of Graduate Studies

Year dc:date

2013

Author dc:creator

• Lin, Paul

Contributors dc:contributor

• Marchant, Roger E.
• Caplan, Arnold I.

• Biology
• Biomedical Engineering
• Medicine
• MSC
• mesenchymal stem cells
• transduction
• lentivrius
• homing
• targeting
• intraarterial
• irradiation injury
• polybrene
• protamine sulfate
• BLI, bioluminescent imaging
• stem cells
• cell engraftment
• cell delivery
• aortic arch
• reporter gene

Statement dc:rights

• unrestricted
• This thesis or dissertation is protected by copyright: all rights reserved. It may not be copied or redistributed beyond the terms of applicable copyright laws.

Language dc:language

English

Repository record dc:identifier

http://rave.ohiolink.edu/etdc/view?acc_num=case1355278573

OAI identifier oai:identifier

oai:etd.ohiolink.edu:case1355278573