Description of Research Expertise

Research Interests
The focus of the laboratory is on gene transfer for genetic disease, with a focus on hemophilia. Studies focus on genetics, molecular biology and biochemistry of blood coagulation factors. We conduct studies in small and large animal models, and in human subjects, exploring the safety and efficacy of gene transfer. A focus of the lab is immune responses in viral vector-mediated gene transfer. We are also investigating safety issues such as integration, and risk of germline transmission. A recent area of investigation is mechanisms of gene correction using zinc finger nucleases and homology-directed repair.

Key words: Hemophilia , AAV, Gene Therapy, Factor IX, Factor VIII.

Description of Research
Major areas of investigation include: 1) structure-function analysis of Factors VII, IX and X through the study of naturally occurring mutant proteins and recombinant proteins produced using site-directed mutagenesis and a mammalian expression system, 2) study of the regulation of expression of the genes encoding the vitamin K dependent clotting factors. These genes manifest tissue-specific expression; they are expressed only in the liver. We have isolated the 5' flanking sequences of all three genes, characterized promoter activity and determined, using DNase footprinting, the location of protein binding sites within these promoters. In the case of Factor X, we have determined through a variety of approaches the identity of the transcription factors binding to the promoter and are in the process of carrying out similar studies on the promoters of VII and IX, 3) studies designed to establish an experimental and clinical basis for gene therapy of hemophilia, a bleeding disorder that results from a deficiency of functional Factor IX. We are currently using both viral vectors to introduce the Factor IX cDNA into target cells of interest. My colleagues and I have several active projects, including a study on the generation and use of recombinant AAV vectors expressing Factor IX to treat hemophilia B. In particular, we are investigating novel methods of delivering vector to target tissues, and are also exploring the use of alternate serotypes and optimized expression cassettes in order to maximize gene expression. Other work focuses on safety problems, including determinants of the immune response to the transgene product, and assessment of risk of germline transmission of vector sequences. In other experiments, we are investigating the function of coagulation proteins through the use of targeted disruption of clotting factor genes. Current areas of interest include completion of clinical trials of an AAV-mediated, liver directed approach.

Rotation Projects for 2008-2009
1. Gene transfer for hemophilia B
2. Immunological aspects of viral vector-based gene transfer
3. Novel approaches to the treatment of hemophilia

Lab personnel:
Shyrie Edmonson, Research Tech
Daniel Hui, Post Doc
Jianhua Liu, Research Tech
Yi-Lin (Emily) Liu, Research Assoc
Paris Margaritis, Research Assoc
Federico Mingozzi, Director, Translational Research
Alex Tai, Research Tech
Yi Zhao, Research Tech
Shang Zhen Zhou, Director, Research Vector Core
Mustafa Yazicioglu, Post Doc
Hojun Li, Pre Doc
Mark Hensley, Pre Doc
Jonathan Finn, Post Doc
Gary Pien, Post Doc
Anand Bhatwat, Pre Doc
Heshue Huang, Research Tech
Harre Downey, Research Tech
Danielle Dunn, Research Tech