Labeling of Porcine Mesenchymal Stem Cells (MSCs) with MRI contrast agent Ferex for use in Abdominal Aortic Aneurysm (AAA) Models

Introduction: Mesenchymal stem cells (MSC) are being investigated in porcine abdominal aortic aneurysm (PAAA) models for their repair potential. This study uses MSCs labeled with the MRI contrast agent Ferex to non-invasively evaluate MSC migration in-vivo. Methods: MSCs from 6 pigs were isolated from bone marrow via Ficoll Paque separation and expanded in culture. Using a Lentiviral vector, MSC from all 6 pigs were transfected with green florescent protein (GFP). MSCs from 4 of these pigs were also labeled with 200μg/ml Ferex using Poly-L-Lysine and then analyzed for Ferex uptake and viability. Preservation of the MSC phenotype was confirmed using flow cytometry by detecting positive CD90 and negative CD45 and CD117. Transmission electron microscopy established that Ferex localized to lysosomes. MSCs were then injected into the adventitia of the PAAA. In-vivo MRI was performed using multiple echo gradient echo sequences. Effective transverse relaxation times (T2* values) were calculated on a pixel-by-pixel basis as a function of time post cell transplantation. Results: Ferex labeled MSCs were visible post transplantation at 4, 11, 15 and 21 days using MRI. The MRI signal void (decreased T2* values) correlated with the presence of Ferex within the PAAA. This signal loss progressively expanded circumferentially at each study interval representing cellular movement. MSC migration and localization were confirmed with GFP visualization on fluorescence microscopy and immunohistochemistry. In-vivo MRI signals also correlate with iron deposition on Perl’s stain. Conclusion: Ferex can be used as an in-vivo tracking agent of MSCs in PAAA models.

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Adipose-Derived Mesenchymal Stem Cells Isolated from Patients with Abdominal Aortic Aneurysm Exhibit Senescence Phenomena

Oxidative Medicine and Cellular Longevity ◽

10.1155/2019/1305049 ◽

2019 ◽

Vol 2019 ◽

pp. 1-12 ◽

Cited By ~ 3

Author(s):

Xiaoran Huang ◽

Hao Zhang ◽

Xiaoting Liang ◽

Yimei Hong ◽

Mengmeng Mao ◽

...

Keyword(s):

Stem Cells ◽

Mesenchymal Stem Cells ◽

Abdominal Aortic Aneurysm ◽

Aortic Aneurysm ◽

Cell Function ◽

Biological Properties ◽

Cell Phenotype ◽

Mitochondrial Morphology ◽

Migration Ability ◽

Abdominal Aortic

Mesenchymal stem cells (MSCs) have shown beneficial effects in the treatment of abdominal aortic aneurysm (AAA). Nonetheless, the biological properties of adipose-derived MSCs (ASCs) from patients with AAA (AAA-ASCs) remain unclear. This study is aimed at investigating the properties of cell phenotype and function of AAA-ASCs compared with ASCs from age-matched healthy donors (H-ASCs). H-ASCs and AAA-ASCs were studied for cell phenotype, differentiation capacity, senescence, and mitochondrial and autophagic functions. Cellular senescence was examined by senescence-associated β-galactosidase (SA-β-gal) staining. Mitochondrial morphology was determined by MitoTracker staining. Despite the similar surface markers of AAA-ASCs and H-ASCs, AAA-ASCs exhibited altered multidifferentiation potential. Compared with H-ASCs, AAA-ASCs displayed enhanced senescence manifested by increased SA-β-gal activity and decreased proliferation and migration ability. Furthermore, AAA-ASCs showed increased mitochondrial fusion, reactive oxygen species (ROS) production, and decreased mitochondrial membrane potential. In addition, AAA-ASCs exhibited decreased autophagy level, upregulation of IL-6 and TNF-α secretion, and downregulation of IL-10 secretion compared with H-ASCs. Nonetheless, treatment of AAA-ASCs with rapamycin (an autophagy activator) dramatically reduced secretion of IL-6 and TNF-α and enhanced secretion of IL-10. In conclusion, our study showed that AAA-ASCs exhibit senescence phenomena and decreased cell function. Understanding the specific alterations in AAA-ASCs will help explore novel strategies to restore cell function for AAA treatment.

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