title: Lentivirus-induced dendritic cells for immunization against high-risk WT1(+) acute myeloid leukemia.
abstract: Wilms' tumor 1 antigen (WT1) is overexpressed in acute myeloid leukemia (AML), a high-risk neoplasm warranting development of novel immunotherapeutic approaches. Unfortunately, clinical immunotherapeutic use of WT1 peptides against AML has been inconclusive. With the rationale of stimulating multiantigenic responses against WT1, we genetically programmed long-lasting dendritic cells capable of producing and processing endogenous WT1 epitopes. A tricistronic lentiviral vector co-expressing a truncated form of WT1 (lacking the DNA-binding domain), granulocyte-macrophage colony-stimulating factor (GM-CSF), and interleukin-4 (IL-4) was used to transduce human monocytes ex vivo. Overnight transduction induced self-differentiation of monocytes into immunophenotypically stable "SmartDC/tWT1" (GM-CSF(+), IL-4(+), tWT1(+), IL-6(+), IL-8(+), TNF-α(+), MCP-1(+), HLA-DR(+), CD86(+), CCR2(+), CCR5(+)) that were viable for 3 weeks in vitro. SmartDC/tWT1 were produced with peripheral blood mononuclear cells (PBMC) obtained from an FLT3-ITD(+) AML patient and surplus material from a donor lymphocyte infusion (DLI) and used to expand CD8(+) T cells in vitro. Expanded cytotoxic T lymphocytes (CTLs) showed antigen-specific reactivity against WT1 and against WT1(+) leukemia cells. SmartDC/tWT1 injected s.c. into Nod.Rag1(-/-).IL2rγc(-/-) mice were viable in vivo for more than three weeks. Migration of human T cells (huCTLs) to the immunization site was demonstrated following adoptive transfer of huCTLs into mice immunized with SmartDC/tWT1. Furthermore, SmartDC/tWT1 immunization plus adoptive transfer of T cells reactive against WT1 into mice resulted in growth arrest of a WT1(+) tumor. Gene array analyses of SmartDC/tWT1 demonstrated upregulation of several genes related to innate immunity. Thus, SmartDC/tWT1 can be produced in a single day of ex vivo gene transfer, are highly viable in vivo, and have great potential for use as immunotherapy against malignant transformation overexpressing WT1.
authors: Department of Hematology, Hemostasis, Oncology and Stem Cell Transplantation, Hannover Medical School, 30625 Hannover, Germany.
authors: Bala Sai
authors: BS
authors: Sundarasetty
authors: Vijay Kumar
authors: VK
authors: Singh
authors: Gustavo
authors: G
authors: Salguero
authors: Robert
authors: R
authors: Geffers
authors: Mareike
authors: M
authors: Rickmann
authors: Laura
authors: L
authors: Macke
authors: Sylvia
authors: S
authors: Borchers
authors: Constanca
authors: C
authors: Figueiredo
authors: Axel
authors: A
authors: Schambach
authors: Urban
authors: U
authors: Gullberg
authors: Elena
authors: E
authors: Provasi
authors: Chiara
authors: C
authors: Bonini
authors: Arnold
authors: A
authors: Ganser
authors: Thomas
authors: T
authors: Woelfel
authors: Renata
authors: R
authors: Stripecke
mesh_terms: D019264:Adoptive Transfer / Q000379:methods*; D000818:Animals; D000970:Antineoplastic Agents / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes; D002454:Cell Differentiation; D002470:Cell Survival; D003713:Dendritic Cells / Q000276:immunology*; D005786:Gene Expression Regulation / Q000276:immunology; D018014:Gene Transfer Techniques; D016162:Genes, Wilms Tumor; D015316:Genetic Therapy; D005822:Genetic Vectors; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000235:genetics / Q000378:metabolism; D006801:Humans; D015847:Interleukin-4 / Q000235:genetics / Q000378:metabolism; D016086:Lentivirus / Q000235:genetics / Q000378:metabolism*; D015470:Leukemia, Myeloid, Acute / Q000276:immunology / Q000628:therapy*; D007963:Leukocytes, Mononuclear / Q000378:metabolism; D008213:Lymphocyte Activation; D051379:Mice; D009000:Monocytes; D020411:Oligonucleotide Array Sequence Analysis; D012307:Risk Factors
chemical_list: D000970:Antineoplastic Agents; D015847:Interleukin-4; D016178:Granulocyte-Macrophage Colony-Stimulating Factor