The Experts below are selected from a list of 276 Experts worldwide ranked by ideXlab platform
Xandra O Breakefield - One of the best experts on this subject based on the ideXlab platform.
-
generation of stable Retrovirus packaging cell lines after transduction with herpes simplex virus hybrid amplicon vectors
Journal of Gene Medicine, 2002Co-Authors: Miguel Senaesteves, Jürgen A. Hampl, Sara M. Camp, Xandra O BreakefieldAbstract:Background A number of properties have relegated the use of Moloney murine leukemia virus (Mo-MLV)-based Retrovirus vectors primarily to ex vivo protocols. Direct implantation of Retrovirus producer cells can bypass some of the limitations, and in situ vector production may result in a large number of gene transfer events. However, the fibroblast nature of most Retrovirus packaging cells does not provide for an effective distribution of vector producing foci in vivo, especially in the brain. Effective development of new Retrovirus producer cells with enhanced biologic properties may require the testing of a large number of different cell types, and a quick and efficient method to generate them is needed. Methods Moloney murine leukemia virus (Mo-MLV) gag-pol and env genes and Retrovirus vector sequences carrying lacZ were cloned into different minimal HSV/AAV hybrid amplicons. Helper virus-free amplicon vectors were used to co-infect glioma cells in culture. Titers and stability of Retrovirus vector production were assessed. Results Simultaneous infection of two glioma lines, Gli-36 (human) and J3T (dog), with both types of amplicon vectors, generated stable packaging populations that produced Retrovirus titers of 0.5–1.2×105 and 3.1–7.1×103 tu/ml, respectively. Alternatively, when cells were first infected with Retrovirus vectors followed by infection with HyRMOVAmpho amplicon vector, stable Retrovirus packaging populations were obtained from Gli-36 and J3T cells producing Retrovirus titers comparable to those obtained with a traditional Retrovirus packaging cell line, ΨCRIPlacZ. Conclusions This amplicon vector system should facilitate generation of new types of Retrovirus producer cells. Conversion of cells with migratory or tumor/tissue homing properties could result in expansion of the spatial distribution or targeting capacity, respectively, of gene delivery by Retrovirus vectors in vivo. Copyright © 2002 John Wiley & Sons, Ltd.
-
single step conversion of cells to Retrovirus vector producers with herpes simplex virus epstein barr virus hybrid amplicons
Journal of Virology, 1999Co-Authors: Miguel Senaesteves, Yoshinaga Saeki, Sara M. Camp, Antonio E Chiocca, Xandra O BreakefieldAbstract:We report here on the development and characterization of a novel herpes simplex virus type 1 (HSV-1) amplicon-based vector system which takes advantage of the host range and retention properties of HSV–Epstein-Barr virus (EBV) hybrid amplicons to efficiently convert cells to Retrovirus vector producer cells after single-step transduction. The Retrovirus genes gag-pol and env (GPE) and retroviral vector sequences were modified to minimize sequence overlap and cloned into an HSV-EBV hybrid amplicon. Retrovirus expression cassettes were used to generate the HSV-EBV-Retrovirus hybrid vectors, HERE and HERA, which code for the ecotropic and the amphotropic envelopes, respectively. Retrovirus vector sequences encoding lacZ were cloned downstream from the GPE expression unit. Transfection of 293T/17 cells with amplicon plasmids yielded Retrovirus titers between 106 and 107 transducing units/ml, while infection of the same cells with amplicon vectors generated maximum titers 1 order of magnitude lower. Retrovirus titers were dependent on the extent of transduction by amplicon vectors for the same cell line, but different cell lines displayed varying capacities to produce Retrovirus vectors even at the same transduction efficiencies. Infection of human and dog primary gliomas with this system resulted in the production of Retrovirus vectors for more than 1 week and the long-term retention and increase in transgene activity over time in these cell populations. Although the efficiency of this system still has to be determined in vivo, many applications are foreseeable for this approach to gene delivery.
-
Single-Step Conversion of Cells to Retrovirus Vector Producers with Herpes Simplex Virus–Epstein-Barr Virus Hybrid Amplicons
Journal of Virology, 1999Co-Authors: Miguel Sena-esteves, Yoshinaga Saeki, Sara M. Camp, E. Antonio Chiocca, Xandra O BreakefieldAbstract:We report here on the development and characterization of a novel herpes simplex virus type 1 (HSV-1) amplicon-based vector system which takes advantage of the host range and retention properties of HSV–Epstein-Barr virus (EBV) hybrid amplicons to efficiently convert cells to Retrovirus vector producer cells after single-step transduction. The Retrovirus genes gag-pol and env (GPE) and retroviral vector sequences were modified to minimize sequence overlap and cloned into an HSV-EBV hybrid amplicon. Retrovirus expression cassettes were used to generate the HSV-EBV-Retrovirus hybrid vectors, HERE and HERA, which code for the ecotropic and the amphotropic envelopes, respectively. Retrovirus vector sequences encoding lacZ were cloned downstream from the GPE expression unit. Transfection of 293T/17 cells with amplicon plasmids yielded Retrovirus titers between 106 and 107 transducing units/ml, while infection of the same cells with amplicon vectors generated maximum titers 1 order of magnitude lower. Retrovirus titers were dependent on the extent of transduction by amplicon vectors for the same cell line, but different cell lines displayed varying capacities to produce Retrovirus vectors even at the same transduction efficiencies. Infection of human and dog primary gliomas with this system resulted in the production of Retrovirus vectors for more than 1 week and the long-term retention and increase in transgene activity over time in these cell populations. Although the efficiency of this system still has to be determined in vivo, many applications are foreseeable for this approach to gene delivery.
Miguel Senaesteves - One of the best experts on this subject based on the ideXlab platform.
-
generation of stable Retrovirus packaging cell lines after transduction with herpes simplex virus hybrid amplicon vectors
Journal of Gene Medicine, 2002Co-Authors: Miguel Senaesteves, Jürgen A. Hampl, Sara M. Camp, Xandra O BreakefieldAbstract:Background A number of properties have relegated the use of Moloney murine leukemia virus (Mo-MLV)-based Retrovirus vectors primarily to ex vivo protocols. Direct implantation of Retrovirus producer cells can bypass some of the limitations, and in situ vector production may result in a large number of gene transfer events. However, the fibroblast nature of most Retrovirus packaging cells does not provide for an effective distribution of vector producing foci in vivo, especially in the brain. Effective development of new Retrovirus producer cells with enhanced biologic properties may require the testing of a large number of different cell types, and a quick and efficient method to generate them is needed. Methods Moloney murine leukemia virus (Mo-MLV) gag-pol and env genes and Retrovirus vector sequences carrying lacZ were cloned into different minimal HSV/AAV hybrid amplicons. Helper virus-free amplicon vectors were used to co-infect glioma cells in culture. Titers and stability of Retrovirus vector production were assessed. Results Simultaneous infection of two glioma lines, Gli-36 (human) and J3T (dog), with both types of amplicon vectors, generated stable packaging populations that produced Retrovirus titers of 0.5–1.2×105 and 3.1–7.1×103 tu/ml, respectively. Alternatively, when cells were first infected with Retrovirus vectors followed by infection with HyRMOVAmpho amplicon vector, stable Retrovirus packaging populations were obtained from Gli-36 and J3T cells producing Retrovirus titers comparable to those obtained with a traditional Retrovirus packaging cell line, ΨCRIPlacZ. Conclusions This amplicon vector system should facilitate generation of new types of Retrovirus producer cells. Conversion of cells with migratory or tumor/tissue homing properties could result in expansion of the spatial distribution or targeting capacity, respectively, of gene delivery by Retrovirus vectors in vivo. Copyright © 2002 John Wiley & Sons, Ltd.
-
single step conversion of cells to Retrovirus vector producers with herpes simplex virus epstein barr virus hybrid amplicons
Journal of Virology, 1999Co-Authors: Miguel Senaesteves, Yoshinaga Saeki, Sara M. Camp, Antonio E Chiocca, Xandra O BreakefieldAbstract:We report here on the development and characterization of a novel herpes simplex virus type 1 (HSV-1) amplicon-based vector system which takes advantage of the host range and retention properties of HSV–Epstein-Barr virus (EBV) hybrid amplicons to efficiently convert cells to Retrovirus vector producer cells after single-step transduction. The Retrovirus genes gag-pol and env (GPE) and retroviral vector sequences were modified to minimize sequence overlap and cloned into an HSV-EBV hybrid amplicon. Retrovirus expression cassettes were used to generate the HSV-EBV-Retrovirus hybrid vectors, HERE and HERA, which code for the ecotropic and the amphotropic envelopes, respectively. Retrovirus vector sequences encoding lacZ were cloned downstream from the GPE expression unit. Transfection of 293T/17 cells with amplicon plasmids yielded Retrovirus titers between 106 and 107 transducing units/ml, while infection of the same cells with amplicon vectors generated maximum titers 1 order of magnitude lower. Retrovirus titers were dependent on the extent of transduction by amplicon vectors for the same cell line, but different cell lines displayed varying capacities to produce Retrovirus vectors even at the same transduction efficiencies. Infection of human and dog primary gliomas with this system resulted in the production of Retrovirus vectors for more than 1 week and the long-term retention and increase in transgene activity over time in these cell populations. Although the efficiency of this system still has to be determined in vivo, many applications are foreseeable for this approach to gene delivery.
Sara M. Camp - One of the best experts on this subject based on the ideXlab platform.
-
generation of stable Retrovirus packaging cell lines after transduction with herpes simplex virus hybrid amplicon vectors
Journal of Gene Medicine, 2002Co-Authors: Miguel Senaesteves, Jürgen A. Hampl, Sara M. Camp, Xandra O BreakefieldAbstract:Background A number of properties have relegated the use of Moloney murine leukemia virus (Mo-MLV)-based Retrovirus vectors primarily to ex vivo protocols. Direct implantation of Retrovirus producer cells can bypass some of the limitations, and in situ vector production may result in a large number of gene transfer events. However, the fibroblast nature of most Retrovirus packaging cells does not provide for an effective distribution of vector producing foci in vivo, especially in the brain. Effective development of new Retrovirus producer cells with enhanced biologic properties may require the testing of a large number of different cell types, and a quick and efficient method to generate them is needed. Methods Moloney murine leukemia virus (Mo-MLV) gag-pol and env genes and Retrovirus vector sequences carrying lacZ were cloned into different minimal HSV/AAV hybrid amplicons. Helper virus-free amplicon vectors were used to co-infect glioma cells in culture. Titers and stability of Retrovirus vector production were assessed. Results Simultaneous infection of two glioma lines, Gli-36 (human) and J3T (dog), with both types of amplicon vectors, generated stable packaging populations that produced Retrovirus titers of 0.5–1.2×105 and 3.1–7.1×103 tu/ml, respectively. Alternatively, when cells were first infected with Retrovirus vectors followed by infection with HyRMOVAmpho amplicon vector, stable Retrovirus packaging populations were obtained from Gli-36 and J3T cells producing Retrovirus titers comparable to those obtained with a traditional Retrovirus packaging cell line, ΨCRIPlacZ. Conclusions This amplicon vector system should facilitate generation of new types of Retrovirus producer cells. Conversion of cells with migratory or tumor/tissue homing properties could result in expansion of the spatial distribution or targeting capacity, respectively, of gene delivery by Retrovirus vectors in vivo. Copyright © 2002 John Wiley & Sons, Ltd.
-
single step conversion of cells to Retrovirus vector producers with herpes simplex virus epstein barr virus hybrid amplicons
Journal of Virology, 1999Co-Authors: Miguel Senaesteves, Yoshinaga Saeki, Sara M. Camp, Antonio E Chiocca, Xandra O BreakefieldAbstract:We report here on the development and characterization of a novel herpes simplex virus type 1 (HSV-1) amplicon-based vector system which takes advantage of the host range and retention properties of HSV–Epstein-Barr virus (EBV) hybrid amplicons to efficiently convert cells to Retrovirus vector producer cells after single-step transduction. The Retrovirus genes gag-pol and env (GPE) and retroviral vector sequences were modified to minimize sequence overlap and cloned into an HSV-EBV hybrid amplicon. Retrovirus expression cassettes were used to generate the HSV-EBV-Retrovirus hybrid vectors, HERE and HERA, which code for the ecotropic and the amphotropic envelopes, respectively. Retrovirus vector sequences encoding lacZ were cloned downstream from the GPE expression unit. Transfection of 293T/17 cells with amplicon plasmids yielded Retrovirus titers between 106 and 107 transducing units/ml, while infection of the same cells with amplicon vectors generated maximum titers 1 order of magnitude lower. Retrovirus titers were dependent on the extent of transduction by amplicon vectors for the same cell line, but different cell lines displayed varying capacities to produce Retrovirus vectors even at the same transduction efficiencies. Infection of human and dog primary gliomas with this system resulted in the production of Retrovirus vectors for more than 1 week and the long-term retention and increase in transgene activity over time in these cell populations. Although the efficiency of this system still has to be determined in vivo, many applications are foreseeable for this approach to gene delivery.
-
Single-Step Conversion of Cells to Retrovirus Vector Producers with Herpes Simplex Virus–Epstein-Barr Virus Hybrid Amplicons
Journal of Virology, 1999Co-Authors: Miguel Sena-esteves, Yoshinaga Saeki, Sara M. Camp, E. Antonio Chiocca, Xandra O BreakefieldAbstract:We report here on the development and characterization of a novel herpes simplex virus type 1 (HSV-1) amplicon-based vector system which takes advantage of the host range and retention properties of HSV–Epstein-Barr virus (EBV) hybrid amplicons to efficiently convert cells to Retrovirus vector producer cells after single-step transduction. The Retrovirus genes gag-pol and env (GPE) and retroviral vector sequences were modified to minimize sequence overlap and cloned into an HSV-EBV hybrid amplicon. Retrovirus expression cassettes were used to generate the HSV-EBV-Retrovirus hybrid vectors, HERE and HERA, which code for the ecotropic and the amphotropic envelopes, respectively. Retrovirus vector sequences encoding lacZ were cloned downstream from the GPE expression unit. Transfection of 293T/17 cells with amplicon plasmids yielded Retrovirus titers between 106 and 107 transducing units/ml, while infection of the same cells with amplicon vectors generated maximum titers 1 order of magnitude lower. Retrovirus titers were dependent on the extent of transduction by amplicon vectors for the same cell line, but different cell lines displayed varying capacities to produce Retrovirus vectors even at the same transduction efficiencies. Infection of human and dog primary gliomas with this system resulted in the production of Retrovirus vectors for more than 1 week and the long-term retention and increase in transgene activity over time in these cell populations. Although the efficiency of this system still has to be determined in vivo, many applications are foreseeable for this approach to gene delivery.
Yoshinaga Saeki - One of the best experts on this subject based on the ideXlab platform.
-
single step conversion of cells to Retrovirus vector producers with herpes simplex virus epstein barr virus hybrid amplicons
Journal of Virology, 1999Co-Authors: Miguel Senaesteves, Yoshinaga Saeki, Sara M. Camp, Antonio E Chiocca, Xandra O BreakefieldAbstract:We report here on the development and characterization of a novel herpes simplex virus type 1 (HSV-1) amplicon-based vector system which takes advantage of the host range and retention properties of HSV–Epstein-Barr virus (EBV) hybrid amplicons to efficiently convert cells to Retrovirus vector producer cells after single-step transduction. The Retrovirus genes gag-pol and env (GPE) and retroviral vector sequences were modified to minimize sequence overlap and cloned into an HSV-EBV hybrid amplicon. Retrovirus expression cassettes were used to generate the HSV-EBV-Retrovirus hybrid vectors, HERE and HERA, which code for the ecotropic and the amphotropic envelopes, respectively. Retrovirus vector sequences encoding lacZ were cloned downstream from the GPE expression unit. Transfection of 293T/17 cells with amplicon plasmids yielded Retrovirus titers between 106 and 107 transducing units/ml, while infection of the same cells with amplicon vectors generated maximum titers 1 order of magnitude lower. Retrovirus titers were dependent on the extent of transduction by amplicon vectors for the same cell line, but different cell lines displayed varying capacities to produce Retrovirus vectors even at the same transduction efficiencies. Infection of human and dog primary gliomas with this system resulted in the production of Retrovirus vectors for more than 1 week and the long-term retention and increase in transgene activity over time in these cell populations. Although the efficiency of this system still has to be determined in vivo, many applications are foreseeable for this approach to gene delivery.
-
Single-Step Conversion of Cells to Retrovirus Vector Producers with Herpes Simplex Virus–Epstein-Barr Virus Hybrid Amplicons
Journal of Virology, 1999Co-Authors: Miguel Sena-esteves, Yoshinaga Saeki, Sara M. Camp, E. Antonio Chiocca, Xandra O BreakefieldAbstract:We report here on the development and characterization of a novel herpes simplex virus type 1 (HSV-1) amplicon-based vector system which takes advantage of the host range and retention properties of HSV–Epstein-Barr virus (EBV) hybrid amplicons to efficiently convert cells to Retrovirus vector producer cells after single-step transduction. The Retrovirus genes gag-pol and env (GPE) and retroviral vector sequences were modified to minimize sequence overlap and cloned into an HSV-EBV hybrid amplicon. Retrovirus expression cassettes were used to generate the HSV-EBV-Retrovirus hybrid vectors, HERE and HERA, which code for the ecotropic and the amphotropic envelopes, respectively. Retrovirus vector sequences encoding lacZ were cloned downstream from the GPE expression unit. Transfection of 293T/17 cells with amplicon plasmids yielded Retrovirus titers between 106 and 107 transducing units/ml, while infection of the same cells with amplicon vectors generated maximum titers 1 order of magnitude lower. Retrovirus titers were dependent on the extent of transduction by amplicon vectors for the same cell line, but different cell lines displayed varying capacities to produce Retrovirus vectors even at the same transduction efficiencies. Infection of human and dog primary gliomas with this system resulted in the production of Retrovirus vectors for more than 1 week and the long-term retention and increase in transgene activity over time in these cell populations. Although the efficiency of this system still has to be determined in vivo, many applications are foreseeable for this approach to gene delivery.
Antonio E Chiocca - One of the best experts on this subject based on the ideXlab platform.
-
single step conversion of cells to Retrovirus vector producers with herpes simplex virus epstein barr virus hybrid amplicons
Journal of Virology, 1999Co-Authors: Miguel Senaesteves, Yoshinaga Saeki, Sara M. Camp, Antonio E Chiocca, Xandra O BreakefieldAbstract:We report here on the development and characterization of a novel herpes simplex virus type 1 (HSV-1) amplicon-based vector system which takes advantage of the host range and retention properties of HSV–Epstein-Barr virus (EBV) hybrid amplicons to efficiently convert cells to Retrovirus vector producer cells after single-step transduction. The Retrovirus genes gag-pol and env (GPE) and retroviral vector sequences were modified to minimize sequence overlap and cloned into an HSV-EBV hybrid amplicon. Retrovirus expression cassettes were used to generate the HSV-EBV-Retrovirus hybrid vectors, HERE and HERA, which code for the ecotropic and the amphotropic envelopes, respectively. Retrovirus vector sequences encoding lacZ were cloned downstream from the GPE expression unit. Transfection of 293T/17 cells with amplicon plasmids yielded Retrovirus titers between 106 and 107 transducing units/ml, while infection of the same cells with amplicon vectors generated maximum titers 1 order of magnitude lower. Retrovirus titers were dependent on the extent of transduction by amplicon vectors for the same cell line, but different cell lines displayed varying capacities to produce Retrovirus vectors even at the same transduction efficiencies. Infection of human and dog primary gliomas with this system resulted in the production of Retrovirus vectors for more than 1 week and the long-term retention and increase in transgene activity over time in these cell populations. Although the efficiency of this system still has to be determined in vivo, many applications are foreseeable for this approach to gene delivery.
