Abstract: The present invention provides polynucleotides and viral vectors for transfection of a mammalian host cell, preferably lentiviral vectors, encoding at least one CAR (chimeric antigen receptors)and a promoter from the Wiskott-Aldrich syndrome locus, in particular the promoter of SEQ. ID NO 1, operably linked to the CAR in order to drive its expression.

Abstract: In the present invention, the inventors have generated a Tet-On all-in-one construct that tightly regulate transgene expression in human stem cells using the original TetR repressor. By using appropriate promoter combinations and shielding the integrative construct with the Is2 insulator, they have constructed the Lent-On-Plus Tet-On system that achieves efficient transgene regulation in human multipotent and pluripotent stem cells. The generation of inducible stem cell lines with the Lent-ON-Plus system did not require selection or cloning, and transgene regulation is maintained after long-term cultured and upon differentiation toward different lineages. The present invention thus offers a solution to the need to improve transgene expression systems in stem cells.

Abstract: The invention relates to expression systems useful for regulated expression of a gene of interest based on the constitutive expression of the original TetR repressor and the expression of the polynucleotide driven by a constitutive promoter operably linked to an operator sequence for a tetracycline operator sequence. The system can be provided as two different polynucleotides or as an all-in-one vector. The invention also relates to vectors, host cells and viral particles according to the invention as well as to the uses thereof for in vitro and in vivo production of products of interest or for therapy.

Abstract: The present invention solves the problem of providing more efficient barrier insulators to avoid vector silencing and to increase expression in the setting of gene transfer vectors, more particularly in the setting of gene transfer retroviral vectors. In this sense, the authors of the present invention have developed an improved insulator element, namely element IS2, which comprises the following combination of nucleic acid molecules, namely nucleic acid molecule HS4-650 bp as shown in SEQ ID No 2 and a synthetic S/MAR nucleic acid molecule containing 5 M/SARs recognition signatures (MRS) as shown in SEQ ID no 1.

Abstract: The invention relates to expression systems useful for regulated expression of a gene of interest based on the constitutive expression of the original TetR repressor and the expression of the polynucleotide driven by a constitutive promoter operably linked to an operator sequence for a tetracycline operator sequence. The system can be provided as two different polynucleotides or as an all-in-one vector. The invention also relates to vectors, host cells and viral particles according to the invention as well as to the uses thereof for in vitro and in vivo production of products of interest or for therapy.

Abstract: The invention relates to expression systems useful for regulated expression of a gene of interest based on the constitutive expression of the original TetR repressor and the expression of the polynucleotide driven by a constitutive promoter operably linked to an operator sequence for a tetracycline operator sequence. The system can be provided as two different polynucleotides or as an all-in-one vector. The invention also relates to vectors, host cells and viral particles according to the invention as well as to the uses thereof for in vitro and in vivo production of products of interest or for therapy.

Abstract: The present invention solves the problem of providing more efficient barrier insulators to avoid vector silencing and to increase expression in the setting of gene transfer vectors, more particularly in the setting of gene transfer retroviral vectors. In this sense, the authors of the present invention have developed an improved insulator element, namely element IS2, which comprises the following combination of nucleic acid molecules, namely nucleic acid molecule HS4-650 bp as shown in SEQ ID No 2 and a synthetic S/MAR nucleic acid molecule containing 5 M/SARs recognition signatures (MRS) as shown in SEQ ID no 1.

Abstract: The invention relates to expression systems useful for regulated expression of a gene of interest based on the constitutive expression of the original TetR repressor and the expression of the polynucleotide driven by a constitutive promoter operably linked to an operator sequence for a tetracycline operator sequence. The system can be provided as two different polynucleotides or as an all-in-one vector. The invention also relates to vectors, host cells and viral particles according to the invention as well as to the uses thereof for in vitro and in vivo production of products of interest or for therapy.