Macular Degeneration and Stem Cell Therapy
What is Macular Degeneration?
Macular Degeneration or Age Related Macular Degeneration (AMD,ARMD) is a eyesight condition which mostly affects older people. AMD results in a loss of vision in the center of the visual field (the macula) because of damage or wear to the retina.
AMD can occur in either a wet or dry types. AMD is a major cause of visual impairment in people of 50 years age or more. AMD can make it difficult or impossible to read or to be able to recognize faces, although enough peripheral vision can remain to allow normal daily life.
Although some macular dystrophies that younger people get are referred to as macular degeneration, the term generally refers to age-related macular degeneration.
Stemming vision loss with stem cells.
J Clin Invest. 2010 Sep 1;120(9):3012-21
Authors: Marchetti V, Krohne TU, Friedlander DF, Friedlander M
Dramatic advances in the field of stem cell research have raised the possibility of using these cells to treat a variety of diseases. The eye is an excellent target organ for such cell-based therapeutics due to its ready accessibility, the prevalence of vasculo- and neurodegenerative diseases affecting vision, and the availability of animal models to demonstrate proof of concept. In fact, stem cell therapies have already been applied to the treatment of disease affecting the ocular surface, leading to preservation of vision. Diseases in the back of the eye, such as macular degeneration, diabetic retinopathy, and inherited retinal degenerations, present greater challenges, but rapidly emerging stem cell technologies hold the promise of autologous grafts to stabilize vision loss through cellular replacement or paracrine rescue effects.
PMID: 20811157 [PubMed - indexed for MEDLINE]
Systemic Injection of RPE65-Programmed Bone Marrow-Derived Cells Prevents Progression of Chronic Retinal Degeneration.
Related Articles Systemic Injection of RPE65-Programmed Bone Marrow-Derived Cells Prevents Progression of Chronic Retinal Degeneration. Mol Ther. 2017 Feb 12;: Authors: Qi X, Pay SL, Yan Y, Thomas J, Lewin AS, Chang LJ, Grant MB, Boulton ME Abstract Bone marrow stem and progenitor cells can differentiate into a range of non-hematopoietic cell types, including retinal pigment epithelium (RPE)-like cells. In this study, we programmed bone marrow-derived cells (BMDCs) ex vivo by inserting a stable RPE65 transgene using a lentiviral vector. We tested the efficacy of systemically administered RPE65-programmed BMDCs to prevent visual loss in the superoxide dismutase 2 knockdown (Sod2 KD) mouse model of age-related macular degeneration. Here, we present evidence that these RPE65-programmed BMDCs are recruited to the subretinal space, where they repopulate the RPE layer, preserve the photoreceptor layer, retain the thickness of the neural retina, reduce lipofuscin granule formation, and suppress microgliosis. Importantly, electroretinography and optokinetic response tests confirmed that visual function was significantly improved. Mice treated with non-modified BMDCs or BMDCs pre-programmed with LacZ did not exhibit significant improvement in visual deficit. RPE65-BMDC administration was most effective in early disease, when visual function and retinal morphology returned to near normal, and less effective in late-stage disease. This experimental paradigm offers a minimally invasive cellular therapy that can be given systemically overcoming the need for invasive ocular surgery and offering the potential to arrest progression in early AMD and other RPE-based diseases. PMID: 28202390 [PubMed - as supplied by publisher]Read more...
Endoscope-Assisted and Controlled Argus II Epiretinal Prosthesis Implantation in Late-Stage Retinitis Pigmentosa: A Report of 2 Cases.
Related Articles Endoscope-Assisted and Controlled Argus II Epiretinal Prosthesis Implantation in Late-Stage Retinitis Pigmentosa: A Report of 2 Cases. Case Rep Ophthalmol. 2016 Sep-Dec;7(3):315-324 Authors: Özmert E, Demirel S Abstract Several different approaches for restoring sight in subjects who are blind due to outer retinal degeneration are currently under investigation, including stem cell therapy, gene therapy, and visual prostheses. Although many different types of visual prostheses have shown promise, to date, the Argus II Epiretinal Prosthesis System, developed in a clinical setting over the course of 10 years, is the world's first and only retinal prosthesis that has been approved by the United States Food and Drug Administration (FDA) and has been given the CE-Mark for sale within the European Economic Area (EEA). The incidence of serious adverse events from Argus II implantation decreased over time after minor changes in the implant design and improvements in the surgical steps used for the procedure had been made. In order to further decrease the scleral incision-related complications and enhance the assessment of the tack position and the contact between the array and the inner macular surface, we used an ophthalmic endoscope during the regular course of Argus II implantation surgery in 2 patients with late-stage retinitis pigmentosa in an attempt to improve the anatomical and functional outcomes. PMID: 28203188 [PubMed]Read more...