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Allison Songstad

Mentor: Budd Tucker, Ph.D.
Lab Room: 4111 MERF
Lab Phone: 319-335-7242

Using patient-specific stem cells to develop treatments for macular disease

The project I am working on involves Best disease, a rare inherited form of dominant juvenile onset macular dystrophy, and age-related macular degeneration (AMD). Both of these diseases are characterized by the dysfunction of the retinal pigment epithelium (RPE), which led many people to think that replacing the RPE would cure macular diseases. However, the Tucker Lab and other collaborating labs believe that the vasculature behind the retina, called the choroid, is defective in these diseases, leading to the death of the RPE layer and photoreceptors. Therefore, my project is to develop a method of differentiating patient-specific induced pluripotent stem cells (iPSCs) into choroid endothelial cells that can be corrected via gene therapy and transplanted back into the patient. Also, very little is known about BEST1, the gene responsible for Best disease. The protein encoded by BEST1, bestrophin, is thought to act as a calcium-activated chloride channel in the RPE layer, but its actual function is still unknown. Thus, another aspect of my project is using BEST1-reporter constructs in iPSC-derived RPE cells generated from Best disease patients for both the elucidation of disease mechanism and as markers of therapeutic efficacy. To do this, I will perform a high-throughput drug screen to determine what small compounds alter BEST1 expression.

Wiley LA, Burnight ER, Songstad AE, Drack AV, Mullins RF, Stone EM, Tucker BA. Patient-specific induced pluripotent stem cells (iPSCs) for the study and treatment of retinal degenerative diseases. Prog Retin Eye Res. 2015 Jan;44:15-35. doi: 10.1016/j.preteyeres.2014.10.002. Epub 2014 Nov 4. Review. PubMed PMID: 25448922.

Giacalone JC, Wiley LA, Burnight ER, Songstad AE, Mullins RF, Stone EM, Tucker BA. Concise Review: Patient-Specific Stem Cells to Interrogate Inherited Eye Disease. Stem Cells Transl Med. 2016 Feb;5(2):132-40. doi:10.5966/sctm.2015-0206. Epub 2015 Dec 18. Review. PubMed PMID: 26683869; PubMed Central PMCID: PMC4729558.

Songstad AE, Wiley LA, Duong K, Kaalberg E, Flamme-Wiese MJ, Cranston CM, Riker MJ, Levasseur D, Stone EM, Mullins RF, Tucker BA. Generating iPSC-Derived Choroidal Endothelial Cells to Study Age-Related Macular Degeneration. Invest Ophthalmol Vis Sci. 2015 Dec;56(13):8258-67. doi: 10.1167/iovs.15-17073. PubMed PMID: 26720480.