Sviluppo di vettori virali per la terapia genica della β−Talassemia

Abstract

Beta−thalassemia major is a severe congenital anemi for which there is presently no curative therapy other than allogeneic hematopoietic stem cell transplantation. This therapeutic option, however, applies only to the minority of thalassemia patients who have an HLA−matched bone marrow donor. Gene therapy by the delivery of a regulated globin gene to autologous hematopoietic stem cells is an attractive alternative approach as it is in principle applicable to all thalassemic subjects. Current vectors, althougheffective in correcting thalassemia in murine models still suffer some drawbacks in terms of safety and also in terms of low titer and expression. The aim of this study was to assemble globin vectors improved in both these aspects. Modifications of the globin cassette in the intron2 and in the LCR of the beta-­‐globin gene can increase the expression of the globin gene without reducing the vector titer. We also examine the variegation in the expression among the different pools of transduce cells and we suppose that the presence of sequences with chromatin opening activity among the segments of b-­‐globin IVS2