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AdCD40L Immunogene Therapy for Bladder Carcinoma
S108
Sa.98 Visualization and Characterisation of Melan A Epitope (25–35)/HLA-A2 Complex by High Affinity Soluble Monoclonal T Cell Receptors (mTCRs) Samantha Paston, Avidex Ltd, Abingdon, Oxfordshire, England, Katherine Adams, Ms, Avidex Ltd, Abingdon, Oxfordshire, England, Giovanna Bossi, Avidex Ltd, Abingdon, Oxfordshire, England, Nathaniel Liddy, Avidex Ltd, Abingdon, Oxfordshire, England, Deborah Sutton, Avidex Ltd, Abingdon, Oxfordshire, England, Tara Mahon, Avidex Ltd, Abingdon, Oxfordshire, England, Peter Molloy, Avidex Ltd, Abingdon, Oxfordshire, England, Emma Gostick, Avidex Ltd, Abingdon, Oxfordshire, England, Andy Sewell, Department of Medical Biochemistry and Immunology, Cardiff, England, Bent Jakobsen, Avidex Ltd, Abingdon, Oxfordshire, England Cytotoxic T cells (CTL) use TCRs to detect tumor and viral antigens. Soluble TCRs are potential tools for therapeutic treatment of cancer, viral infections and autoimmune diseases. The Melan A protein (MART-1) was one of the first tumour associated antigens to be identified, and is over-expressed in 80–100% of melanomas. CTL’s recognising the heterolytic ELAGIGILTV peptide can be found in both healthy donors and melanoma patients. Adoptive therapy and vaccination trials using the ELAGIGILTV peptide have resulted in some good clinical responses with partial or complete regression of some metastates. In healthy donors, up to 0.1% of Tcells in peripheral blood can be stained with the Melan A tetramer; patients have a higher frequency of Melan A specific Tcells where 1–15% of the T cells can be stained with the tetramer. The Melan A mTCR was affinity matured to bind HLA-A2 presenting the heteroclytic ELAGIGILTV peptide with a kDa of 10 pM and a half life of 67 h. Here we describe the generation of a Tcell clone specific for the HLA-A2/Melan A epitope (26–35) derived from a healthy blood donor. Using this Melan A (26–35) mTCR we can specifically block cytokine production from a Melan A T cell clone. In addition we are also able to detect and quantify the endogenous peptide processed and presented by melanoma cell lines using 3D fluoresence microscopy and flow cytometry. Visualisation and quantification of these specific antigen/MHC complexes enable the potential of mTCRs recognising these complexes as anticancer therapeutics to be evaluated. doi:10.1016/j.clim.2007.03.486
Sa.100 AdCD40L Immunogene Therapy for Bladder Carcinoma Moa Fransson, PhD Student, Clinical Immunology Division, Uppsala, Sweden, Angelica Loskog, Scientist, Clinical Immunology Division, Uppsala, Sweden, Thomas Tötterman, Profesor, Clinical Immunology Division, Uppsala, Sweden Recently regulatory T cells (Treg) have made a comeback in the immunological arena and the role of these cells in cancer is in focus. Clinical protocols that effectively counteract Tregmediated immunosuppression are in high demand. We developed an immunostimulatory gene therapy for urinary bladder cancer based on CD40L gene transfer into the tumor site. The efficacy of this therapy was evaluated in mouse and human
Abstracts experimental models of bladder cancer. The CD40L gene was transferred to the bladder wall of tumor-bearing mice by adenoviral vector instillation. AdCD40L gene therapy cured 60% of mice with pre-established aggressive tumors. Cured mice were completely resistant to s.c. challenge with wt tumor. The mRNA levels of the Treg transcription factor Foxp3 were measured in tumor biopsies and lymph nodes. There were no differences within the tumors of the different treatment groups. However, Foxp3 mRNA levels were down-regulated in the lymph nodes of AdCD40L treated mice. Human bladder cancer cell line cells were transduced with AdCD40L vector and used to stimulate immune cells. Cytokine and immune cell profiling indicated a Th1 type response. The AdCD40L-modified cell lines stimulated maturation of dendritic cells and cytotoxic Tcells as opposed to wt tumor cells. In conclusion, CD40L gene transfer evokes Th1 cytokine responses and counteracts Tregulatory cell development and/or function in the preclinical setting. We are currently conducting a phase I/II trial with AdCD40L in patients with bladder cancer. doi:10.1016/j.clim.2007.03.487
Sa.101 Functional T Cell Responses to Tumor Antigens in Breast Cancer Patients Have a Unique Phenotype and Cytokine Signature Margaret Inokuma, Scientist, BD Biosciences, Immune Function, San Jose, CA, Corazon dela Rosa, Research Associate, University of Washington, Seattle, WA, Perry Haaland, BD Fellow, BD Technologies, Research Triangle Park, NC, Douglas Petry, patent attorney, BD Biosciences, San Jose, CA, Janet Siebert, president, CytoAnalytics, Denver, CO, MengXiang Tang, Senior Algorithm Developer, BD Biosciences, San Jose, CA, John Dunne, Associate Director, BD Biosciences, San Jose, CA, Vernon Mai, Director, BD Biosciences, San Jose, CA, Mary Disis, Associate Professor, University of Washington, Department of Oncology, Seattle, WA, Holden Maecker, Research Grp Manager, BD Biosciences, San Jose, CA The prevalence with which endogenous tumor antigens induce host T cell responses is unclear. Even when such responses are detected, they do not usually result in spontaneous remission of the cancer. We hypothesized that this might be associated with a predominant phenotype and/or cytokine profile of tumor-specific responses that is different from protective Tcell responses to other chronic antigens, such as cytomegalovirus (CMV). We detected significant T cell responses to CEA, HER-2/neu, and/or MAGE-3 in 17 of 21 breast cancer patients naive to immunotherapy. The pattern of T cell cytokines produced in response to tumor-associated antigens (TAAs) in breast cancer patients was significantly different from that produced in response to CMV in the same patients. Specifically, there was a higher proportion of IL-2 producing CD8+ T cells, and a lower proportion of IFN γproducing CD4+ and CD8+ T cells responding to TAAs compared to CMV antigens. Finally, the phenotype of TAA-responsive CD8+ T cells in breast cancer patients was almost completely CD28 +CD45RA− (central memory phenotype). CMV-responsive CD8+ T cells in the same patients were broadly distributed among phenotypes, and contained a high proportion of terminal
Sa.98 Visualization and Characterisation of Melan A Epitope (25–35)/HLA-A2 Complex by High Affinity Soluble Monoclonal T Cell Receptors (mTCRs) Samantha Paston, Avidex Ltd, Abingdon, Oxfordshire, England, Katherine Adams, Ms, Avidex Ltd, Abingdon, Oxfordshire, England, Giovanna Bossi, Avidex Ltd, Abingdon, Oxfordshire, England, Nathaniel Liddy, Avidex Ltd, Abingdon, Oxfordshire, England, Deborah Sutton, Avidex Ltd, Abingdon, Oxfordshire, England, Tara Mahon, Avidex Ltd, Abingdon, Oxfordshire, England, Peter Molloy, Avidex Ltd, Abingdon, Oxfordshire, England, Emma Gostick, Avidex Ltd, Abingdon, Oxfordshire, England, Andy Sewell, Department of Medical Biochemistry and Immunology, Cardiff, England, Bent Jakobsen, Avidex Ltd, Abingdon, Oxfordshire, England Cytotoxic T cells (CTL) use TCRs to detect tumor and viral antigens. Soluble TCRs are potential tools for therapeutic treatment of cancer, viral infections and autoimmune diseases. The Melan A protein (MART-1) was one of the first tumour associated antigens to be identified, and is over-expressed in 80–100% of melanomas. CTL’s recognising the heterolytic ELAGIGILTV peptide can be found in both healthy donors and melanoma patients. Adoptive therapy and vaccination trials using the ELAGIGILTV peptide have resulted in some good clinical responses with partial or complete regression of some metastates. In healthy donors, up to 0.1% of Tcells in peripheral blood can be stained with the Melan A tetramer; patients have a higher frequency of Melan A specific Tcells where 1–15% of the T cells can be stained with the tetramer. The Melan A mTCR was affinity matured to bind HLA-A2 presenting the heteroclytic ELAGIGILTV peptide with a kDa of 10 pM and a half life of 67 h. Here we describe the generation of a Tcell clone specific for the HLA-A2/Melan A epitope (26–35) derived from a healthy blood donor. Using this Melan A (26–35) mTCR we can specifically block cytokine production from a Melan A T cell clone. In addition we are also able to detect and quantify the endogenous peptide processed and presented by melanoma cell lines using 3D fluoresence microscopy and flow cytometry. Visualisation and quantification of these specific antigen/MHC complexes enable the potential of mTCRs recognising these complexes as anticancer therapeutics to be evaluated. doi:10.1016/j.clim.2007.03.486
Sa.100 AdCD40L Immunogene Therapy for Bladder Carcinoma Moa Fransson, PhD Student, Clinical Immunology Division, Uppsala, Sweden, Angelica Loskog, Scientist, Clinical Immunology Division, Uppsala, Sweden, Thomas Tötterman, Profesor, Clinical Immunology Division, Uppsala, Sweden Recently regulatory T cells (Treg) have made a comeback in the immunological arena and the role of these cells in cancer is in focus. Clinical protocols that effectively counteract Tregmediated immunosuppression are in high demand. We developed an immunostimulatory gene therapy for urinary bladder cancer based on CD40L gene transfer into the tumor site. The efficacy of this therapy was evaluated in mouse and human
Abstracts experimental models of bladder cancer. The CD40L gene was transferred to the bladder wall of tumor-bearing mice by adenoviral vector instillation. AdCD40L gene therapy cured 60% of mice with pre-established aggressive tumors. Cured mice were completely resistant to s.c. challenge with wt tumor. The mRNA levels of the Treg transcription factor Foxp3 were measured in tumor biopsies and lymph nodes. There were no differences within the tumors of the different treatment groups. However, Foxp3 mRNA levels were down-regulated in the lymph nodes of AdCD40L treated mice. Human bladder cancer cell line cells were transduced with AdCD40L vector and used to stimulate immune cells. Cytokine and immune cell profiling indicated a Th1 type response. The AdCD40L-modified cell lines stimulated maturation of dendritic cells and cytotoxic Tcells as opposed to wt tumor cells. In conclusion, CD40L gene transfer evokes Th1 cytokine responses and counteracts Tregulatory cell development and/or function in the preclinical setting. We are currently conducting a phase I/II trial with AdCD40L in patients with bladder cancer. doi:10.1016/j.clim.2007.03.487
Sa.101 Functional T Cell Responses to Tumor Antigens in Breast Cancer Patients Have a Unique Phenotype and Cytokine Signature Margaret Inokuma, Scientist, BD Biosciences, Immune Function, San Jose, CA, Corazon dela Rosa, Research Associate, University of Washington, Seattle, WA, Perry Haaland, BD Fellow, BD Technologies, Research Triangle Park, NC, Douglas Petry, patent attorney, BD Biosciences, San Jose, CA, Janet Siebert, president, CytoAnalytics, Denver, CO, MengXiang Tang, Senior Algorithm Developer, BD Biosciences, San Jose, CA, John Dunne, Associate Director, BD Biosciences, San Jose, CA, Vernon Mai, Director, BD Biosciences, San Jose, CA, Mary Disis, Associate Professor, University of Washington, Department of Oncology, Seattle, WA, Holden Maecker, Research Grp Manager, BD Biosciences, San Jose, CA The prevalence with which endogenous tumor antigens induce host T cell responses is unclear. Even when such responses are detected, they do not usually result in spontaneous remission of the cancer. We hypothesized that this might be associated with a predominant phenotype and/or cytokine profile of tumor-specific responses that is different from protective Tcell responses to other chronic antigens, such as cytomegalovirus (CMV). We detected significant T cell responses to CEA, HER-2/neu, and/or MAGE-3 in 17 of 21 breast cancer patients naive to immunotherapy. The pattern of T cell cytokines produced in response to tumor-associated antigens (TAAs) in breast cancer patients was significantly different from that produced in response to CMV in the same patients. Specifically, there was a higher proportion of IL-2 producing CD8+ T cells, and a lower proportion of IFN γproducing CD4+ and CD8+ T cells responding to TAAs compared to CMV antigens. Finally, the phenotype of TAA-responsive CD8+ T cells in breast cancer patients was almost completely CD28 +CD45RA− (central memory phenotype). CMV-responsive CD8+ T cells in the same patients were broadly distributed among phenotypes, and contained a high proportion of terminal