All ETDs from UAB

Document Type

Dissertation

Date of Award

2008

Degree Name by School

Doctor of Philosophy (PhD) Heersink School of Medicine

Abstract

The hematological disorder sickle cell disease (SCD) is a prevalent human genetic disease. It causes severe tissue damage that can result in strokes, splenic infarction, kidney failure, liver and lung disorders, painful crises, and other complications. Although palliative therapies and allogenic stem cell transplantation therapies have been developed for this disorder, there is still no optimal treatment and SCD patients continue to suffer significant morbidity. Recently, several powerful technologies have been developed that increase the possibility for developing therapeutic treatments for SCD. Previously, our lab group demonstrated that SCD can be corrected in our humanized mouse model by transduction of hematopoietic stem cells with lentiviral vectors containing an antisickling globin gene. However, concerns about insertional mutagenesis persist. The ideal correction would involve replacement of the sickle globin gene with a normal copy of the beta-globin gene by homologous recombination. Using this technique, we successfully corrected the sickle mutation in a novel knock-in mouse model of SCD. The animals produce high levels of normal human hemoglobin (HbA) and the pathology associated with SCD is corrected. Furthermore, in collaboration with our colleagues at MIT, we recently corrected sickle cell disease in our knockin mouse model by reprogramming skin iii fibroblasts into iPS (induced Pluripotent Stem) cells, replacing the defective sickle betaglobin gene with a normal beta globin gene, differentiating the corrected iPS cells into hematopoietic progenitors and transplanting these cells into irradiated sickle mouse recipients. Over 50% of the hemoglobin in red blood cells of the treated mice was HbA, and the disease was corrected. This is the first demonstration of the use of iPS cells for the successful treatment of a hereditary disease. These experiments provide a foundation the development of a similar strategy to correct sickle cell disease in human patients.

Share

COinS