Bluebird Bio, Inc.

Massachusetts Institute of Technology

Genetix Pharmaceuticals, Inc.

Albert Einstein College of Medicine

Karen Westerman

Philippe Leboulch

Robert Pawliuk

Philippe Louis Leboulch

Philippe LeBoulch

Eric Bouhassira

Ken Julian Takekoshi

Provided are improved compositions and methods for achieving gene therapy in hematopoietic cells and hematopoietic precursor cells, including erythrocytes, erythroid progenitors, and embryonic stem cells. Also provided are improved gene therapy methods for treating hematopoietic-related disorders. Retroviral gene therapy vectors that are optimized for erythroid specific expression and treatment of hemoglobinopathic conditions are disclosed.

Therapeutic retroviral vectors for gene therapy

The invention provides improved compositions and methods for achieving gene therapy in hematopoietic cells and hematopoietic precursor cells, including erythrocytes, erythroid progenitors, and embryonic stem cells. The invention further provides improved gene therapy methods for treating hematopoietic-related disorders. Retroviral gene therapy vectors that are optimized for erythroid specific expression and treatment of hemoglobinopathic conditions are disclosed.

Novel packaging cell lines which produce recombinant retrovirus, free of detectable helper-virus are disclosed. Also disclosed are methods of making the cell lines and methods of producing recombinant retroviruses from the cell lines. Retroviruses produced by the cell lines include lentiviruses, such as HIV, capable of transfering heterologous DNA to a wide range of non-dividing cells. The packaging cells contain at least three vectors which collectively encode retroviral gag, pol, and env proteins, wherein the gag and pol genes are separated, in part, onto two or more different vectors. This is made possible by fusing Vpr or Vpx to pol proteins separated from gag so that the proteins are targeted to assembling virions. Among other advantages, the packaging cells provide the benefit of increased safety when used in human gene therapy by virtually eliminating the possibility of molecular recombination leading to production of replication competent helper virus.

Lentiviral packaging cells and uses therefor

Lentiviral packaging cells

Novel packaging cell lines which produce recombinant retrovirus, free of detectable helper-virus are disclosed. Also disclosed are methods of making the cell lines and methods of producing recombinant retroviruses from the cell lines. Retroviruses produced by the cell lines include lentiviruses, such as HIV, capable of transfering heterologous DNA to a wide range of non-dividing cells. The packaging cells contain at least three vectors which collectively encode retroviral gag, pol, and env proteins, wherein the gag and pol genes are separated, in part, onto two or more different vectors. This is made possible by fusing Vpr or Vpx to pol proteins separated from gag so that the proteins are targeted to assembling virions. Among other advantages, the packaging cells provide the benefit of increased safety when used in human gene therapy by virtually eliminating the possibility of molecular recombination leading to production of replication-competant helper virus.

Methods and compositions for transforming cells, resulting in efficient and stable site-specific integration of transgenes, are disclosed. Transformation is achieved by introducing into a cell an acceptor vector, preferably a retroviral vector, which integrates into the genome of the cell. The acceptor vector comprises two incompatible lox sequences, L1 and L2. A donor vector is then introduced into the cell comprising a transgene flanked by the same L1 and L2 sequences. Stable gene transfer is initiated by contacting the lox L1 and L2 sequences with Cre recombinase.

Growing community of inventors

Reading, MA, United States of America

Karen Westerman