Setting-up of a chimeric animal model to verify the role of bone marrow-derived endothelial progenitor cells in the development of age-related macular degeneration (AMD).
Silvia Maestroni1, Anna Maestroni1, Mandelli Giacomo1, Giuliana Ferrari1, Ilaria Zucchiatti1, Rosangela Lattanzio1, Gemma Tremolada1, Simona Ceglia1, Francesco Bandello1, Gianpaolo Zerbini1
1Ospedale San Raffaele s.r.l., Milan, Italy
Age-related macular degeneration (AMD) is a debilitating disease that causes vision loss and represents the leading cause of blindness in industrialized countries among adults older than 60 years. Most cases of severe vision loss in AMD result from the development of choroidal neovascularization (CNV), which occurs in approximately 10% of patients with AMD. The abnormal new blood vessels grow from the choroidal capillaries through Bruch’s membrane and into the spaces beneath the retinal pigment epithelium and the retina.
The mechanisms that cause CNV are still unclear, but it is known that once the process is triggered, the lesion grows rapidly. In humans, the therapeutic benefit of intravitreal injections of agents that target vascular endothelial growth factor (VEGF) indicates that angiogenesis (the process that involves the migration, proliferation, and remodeling of endothelial cells derived from preexisting vessels) is one of the processes that sustain the rapid formation of the new capillaries in CNV. A parallel role of endothelial progenitor cells (EPCs) recruited to the process from bone marrow (so called vasculogenesis) cannot however be presently ruled out.
To verify this issue, bone marrow transplantation was performed in 20 C57BL mice using a GFP transgenic strain as a donor and a co-isogenic strain as the recipient. Choroidal neovascolarization was then induced by laser treatment aimed to obtain a major retinal damage (disrupture of Bruch's membrane), a procedure that gave rise to choroidal neovascularization approximately 15 days after treatment.
Choroidal neovascularization was confirmed in vivo by simultaneous Fluorescein Angiography and Optical Coherence Tomography (OCT) (Spectralis™ device from Heidelberg Engineering). After this procedure, the animals were perfused with TRITC-labeled dextrans to highlight retinal vascularization and sacrificed. The eyes were then removed, the retina extracted and treated appropriately to obtain retinal whole-mounts. Under fluorescence the perfused retinal vascular tree could be evaluated and EPCs were detectable along the vessels being GFP+. Staining to confirm EPCs phenotype was performed and quantification of EPCs involvement in neovascularization was performed by analysis of digital pictures. Altogether our results confirmed this chimeric mouse as a valid model of AMD of potential use to test the effect of novel drugs on the onset and progression of this sight-threatening disease.
By viewing the material on this site you understand and
The opinions and statements expressed on this site reflect the
views of the author or authors and do not necessarily reflect those of
The Transplantation Society and/or its Sections.
The hosting of material on The Transplantation Society site does
not signify endorsement of this material by The Transplantation Society
and/or its Sections.
The material is solely for educational purposes for qualified
health care professionals.
The Transplantation Society and/or its Sections are not liable for
any decision made or action taken based on the information contained in
the material on this site.
The information cannot be used as a substitute for professional
The information does not represent a standard of care.
No physician-patient relationship is being established.
The Transplantation Society
505 Boulevard René-Lévesque Ouest
Montréal, QC, H2Z 1Y7