cAncer - iMMunotherApy: designer effector cells
`
`Engineering CD20-Specific Chimeric
`37.
`Receptor Redirected T Cells with Inducible Co-
`Expression of a Caspase-9 Based Suicide Switch
`for Adoptive Immunotherapy of Mantle Cell
`Lymphoma
`Lihua Pan,1 Carolina Berger,1 Yukang Lin,1 Jinjuan Wang,1 Stanley
`R. Riddell,1 Oliver W. Press.1
`1Clincial Research Division, Fred Hutchinson Cancer Research
`Center, Seattle, WA.
`Mantle Cell Lymphoma (MCL) is a distinct clinicopathologic
`subtype of Non-Hodgkin’s Lymphoma (NHL) that afflicts around
`5000 North Americans each year and is considered incurable by
`conventional treatment, with a median survival of 2-3 years. Surface
`expression of the CD20 molecule is an invariant feature of MCL cells.
`Work from our laboratory using T cells bearing a transfected CD20-
`specific chimeric T cell receptor (cTCR) has demonstrated promise
`in a murine model and a phase I clinical trial. However, limitations
`including low transfection efficiency, low surface expression of cTCR,
`and risk of insertional mutagenesis hinder the further exploitation of
`this approach. Here we describe a new immunotherapeutic approach
`for treatment of MCL using autologous T lymphocytes that have
`been genetically modified with a bicistronic IRES retroviral vector
`to express both a cTCR recognizing the human CD20 antigen and
`a suicide gene using inducible activation of caspase 9. The cTCR
`gene was designed to encode a SP163 translational enhancer, a
`1F5scFvFc anti-CD20 recognition domain, CD28 and CD137 co-
`stimulatory domains, and a CD3ζ signaling region for maximal
`expression, activation and cytolytic activity. Transduced Jurkat T
`cells display robust and sustained surface expression of the chimeric
`T cell receptor for more than 6 months. When exposed to chemical
`inducers of dimerization (CID), only Jurkat T cells transduced with
`both cTCR and iCas-9 genes but not cTCR alone underwent CID-
`induced caspase-mediated apoptosis. The same constructs were also
`tested in primary human T cells in vitro. We have been able to achieve
`transduction efficiency ranging from 15% to 70%. All transduced
`primary T cells expressed the cTCR at a level 10 to 100 fold higher
`than cells transfected with naked DNA plasmids encoding a similar
`cTCR. These cTCR+ T cells are able to execute highly effective
`cytolytic functions when cultured together with 51Cr-labeled CD20+
`lymphoma cell lines including EL4-CD20, Daudi and Granta, a
`MCL cell line. They had no effect on CD20-negative cell lines.
`This demonstrates the high specificity of the modified T cells. We
`detected CID induced activation of caspase activity and elimination
`of T cells transduced with both cTCR and iCas-9 genes via flow
`cytometric-based analysis, whereas CID had no effect on control T
`cells transduced with cTCR alone. In vivo testing of these T cells will
`be carried out in a murine MCL model as well as in a non-human
`primate Macaca nemestrina model in the near future. Our work
`demonstrates the feasibility and promise of this approach in treating
`relapsed MCL and other CD20 bearing B cell malignancies in a safer
`and more efficient manner.
`
` Molecular Therapy Volume 16, Supplement 1, May 2008
` Copyright © The American Society of Gene Therapy
`
`A Phase I Trial for the Treatment of Chemo-
`38.
`Refractory Chronic Lymphocytic Leukemia with
`CD19-Targeted Autologous T Cells
`Renier J. Brentjens,1 Daniel R. Hollyman,3 Mark Weiss,1 Jolanta
`Stefanski,3 Mark Przybylowski,3 Shirley Bartido,3 Oriana Borquez-
`Ojeda,3 Clare Taylor,3 James Hosey,3 Mark Heaney,1 Michel
`Sadelain,1,2,3 Isabelle Riviere.1,2,3
`1Department of Medicine, Memorial Sloan-Kettering Cancer
`Center, New York, NY; 2Molecular Pharmacology & Chemistry
`Program, Memorial Sloan-Kettering Cancer Center, New
`York, NY; 3Gene Transfer & Somatic Cell Engineering Facility,
`Memorial Sloan-Kettering Cancer Center, New York, NY.
`Building on our earlier demonstration that human peripheral blood T
`cells genetically targeted to CD19 can eradicate established, systemic
`B cell tumors in mice, we have developed a novel immunotherapy for
`the treatment of chronic lymphocytic leukemia (CLL). This strategy
`is based on the genetic modification of patient T cells to recognize
`the B cell-specific cellular antigen CD19, expressed on B cell tumors,
`through the retroviral expression of a chimeric antigen receptor
`(CAR) specific for CD19 (19-28z). We have initiated a clinical trial
`utilizing 19-28z+ autologous T cells in patients with purine analog-
`refractory chronic lymphocytic leukemia (CLL) (BB-IND 13266).
`Enrolled patients initially undergo a leukopheresis procedure in order
`to obtain T cells. Following activation with Dynabeads® ClinExVivo
`CD3/CD28 magnetic beads, the T cells are transduced with the CD19
`specific 19-28z CAR using cGMP gammaretroviral vector stocks
`generated in our facility, and expanded utilizing a WaveTM bioreactor
`platform-based rapid expansion protocol. To assess safety, patients
`enrolled in the first cohort of this trial received an infusion of the
`lowest planned dose of modified T cells alone. Subsequent cohorts
`will receive infusions of 19-28z+ T cells following escalating doses
`of cyclophosphamide chemotherapy. Patients treated in the first
`cohort with the lowest modified T cell dose alone experienced grade
`2 fevers and rigors during infusion but no dose limiting toxicities.
`Treated patients variably experienced decrease in lymph node size,
`decreased CD19+ B cell numbers in the peripheral blood, and a
`decreased dependence on red blood cell transfusions. We conclude
`so far that infusion of CD19-targeted T cells alone is well tolerated
`in patients with refractory CLL, with objective evidence of transient
`anti-tumor responses. Patients on the second cohort, who will receive
`prior lymphodepleting chemotherapy with cyclophosphamide, are
`being enrolled. The trial presented here is the first to utilize gene
`modified autologous T cells for the treatment of CLL, as well as
`the first to target CD19+ tumors utilizing a rapid T cell expansion
`protocol, which represents a promising approach for patients with
`B cell malignancies.
`
`Cross-Talk between Tumor Cells and
`39.
`Endothelium Triggers a Strong Chemotactic
`Signal Recruiting T Lymphocytes to Distant Tumor
`Deposits
`Nabil Ahmed,1 Vita Salsman,1 Kwong-Hon Chow,1 Huseyin
`Kadikoy,1 Xia-Nan Li,1 Laszlo Perlaky,1 Meenakshi Bhattacharjee,2
`Cliona Rooney,1 Helen Heslop,1 Stephen Gottschalk.1
`1Center for Cell and Gene Therapy, Baylor College of Medicine,
`Houston, TX; 2Pathology, Texas Children’s Hospital, Houston, TX.
`Background: Failure of local control of medulloblastoma (MB)
`is a poor prognostic factor that heralds incurable disease recurrence
`that is multi-focal in up to 60% of patients, adding to the dismal
`prognosis of these patients. We have shown that genetically modified
`T cells expressing HER2-specific chimeric antigen receptors (HER2-T
`cells) induce regression of HER2+ human MB growing in the brains
`of mice after intratumoral injection. The objective of this project
`was to study the ability of HER2-T cells to achieve loco-regional
`S15
`
`UPenn Ex. 2014
`Miltenyi v. UPenn
`IPR2022-00853
`
`