INVESTIGADORES
DEWEY Ricardo Alfredo
congresos y reuniones científicas
Título:
Generation of novel self-inactivating retroviral vectors for gene therapy of Wiskott-Aldrich-Syndrome.
Autor/es:
INES AVEDILLO DÍEZ; RICARDO A. DEWEY; AXEL SCHAMBACH; CHRISTOPHER BAUM; CHRISTOPH KLEIN
Lugar:
Wilsede, Germany
Reunión:
Jornada; XX. Jahrestagung der Kind-Philipp-Stiftung für Leukämieforschung. Zentrum für Frauen- Kinder- und Jugendmedizin Klinik für pädiatische Hämatologie und Onkologie.; 2007
Institución organizadora:
Kind-Philipp-Stiftung für Leukämieforschung. Zentrum für Frauen- Kinder- und Jugendmedizin Klinik für pädiatische Hämatologie und Onkologie.
Resumen:
Hematopoietic stem cell gene therapy has been very effective in various monogenic
immunodeficiency diseases. However, insertional mutagenesis remains an important
concern. To develop retroviral vectors with improved safety features, we have generated a
series of self-inactivating (SIN) constructs designed to express WASP in hematopoietic
cells. We comparatively assessed four internal promoters derived from Spleen Focus
Forming Virus (SF), Elongation Factor 1-á (EFS), Phosphoglycerate Kinase (PGK) and
Wiskott-Aldrich Syndrome Protein (WASP), respectively. Upon retroviral gene transfer,
we analyzed gene expression in various hematopoietic and non-hematopoietic cell lines,
using GFP expression as a readout parameter. Among the four internal promoters tested,
EFS and SF were found to induce the highest expression levels in all cell lines tested. As
expected, the endogenous WASP promoter was only active in hematopoietic cells. For
further studies, we focussed on the EFS promoter. EBV-LCL cell lines from WAS
patients were transduced and shown to reconstitute their aberrant cytoskeleton. This
reconstitution was comparable to cells corrected with a classical LTR-driven WASP
vector. We are currently performing toxicity assays, gene transfer into human CD34+
cells, and in vivo reconstitution studies in the WASP-deficient mouse system to further
assess the suitability of novel SIN vectors as a potential way to improve the safety profile
of WASP-expressing vectors. Our data suggest that novel retroviral SIN vectors may be
an alternative to conventional LTR-deriven retroviral vectors for future human gene
therapy studies in WASP-deficient patients.