Assuntos
Antígenos Glicosídicos Associados a Tumores/imunologia , Imunoterapia Adotiva , Receptores de Antígenos de Linfócitos T/metabolismo , Receptores de Antígenos Quiméricos/metabolismo , Linfócitos T/imunologia , Animais , Biomarcadores Tumorais , Citotoxicidade Imunológica , Modelos Animais de Doenças , Humanos , Imunoterapia Adotiva/métodos , Camundongos , Neoplasias/imunologia , Neoplasias/metabolismo , Neoplasias/patologia , Neoplasias/terapia , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos Quiméricos/genética , Linfócitos T/metabolismo , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
The adoptive transfer of CD19-specific chimeric antigen receptor engineered T cells (CAR T cells) resulted in encouraging clinical trials in indolent B-cell malignancies. However, they also show the limitations of this fascinating technology: CAR T cells can lead to even life-threatening off-tumor, on-target side effects if CAR T cells crossreact with healthy tissues. Here, we describe a novel modular universal CAR platform technology termed UniCAR that reduces the risk of on-target side effects by a rapid and reversible control of CAR T-cell reactivity. The UniCAR system consists of two components: (1) a CAR for an inert manipulation of T cells and (2) specific targeting modules (TMs) for redirecting UniCAR T cells in an individualized time- and target-dependent manner. UniCAR T cells can be armed against different tumor targets simply by replacement of the respective TM for (1) targeting more than one antigen simultaneously or subsequently to enhance efficacy and (2) reducing the risk for development of antigen-loss tumor variants under treatment. Here we provide 'proof of concept' for retargeting of UniCAR T cells to CD33- and/or CD123-positive acute myeloid leukemia blasts in vitro and in vivo.
Assuntos
Regulação da Expressão Gênica , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/imunologia , Receptores de Antígenos de Linfócitos T/genética , Linfócitos T/imunologia , Linfócitos T/metabolismo , Animais , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/imunologia , Antígenos de Neoplasias/metabolismo , Citocinas/metabolismo , Citotoxicidade Imunológica , Modelos Animais de Doenças , Vetores Genéticos/genética , Humanos , Imunoterapia Adotiva/métodos , Subunidade alfa de Receptor de Interleucina-3/genética , Subunidade alfa de Receptor de Interleucina-3/imunologia , Subunidade alfa de Receptor de Interleucina-3/metabolismo , Lentivirus/genética , Leucemia Mieloide Aguda/patologia , Leucemia Mieloide Aguda/terapia , Camundongos , Camundongos Knockout , Receptores de Antígenos de Linfócitos T/imunologia , Receptores de Antígenos de Linfócitos T/metabolismo , Lectina 3 Semelhante a Ig de Ligação ao Ácido Siálico/genética , Lectina 3 Semelhante a Ig de Ligação ao Ácido Siálico/imunologia , Lectina 3 Semelhante a Ig de Ligação ao Ácido Siálico/metabolismo , Transdução Genética , Carga TumoralRESUMO
Bispecific antibodies (bsAbs) engaging T cells are emerging as a promising immunotherapeutic tool for the treatment of hematologic malignancies. Because their low molecular mass, bsAbs have short half-lives. To achieve clinical responses, they have to be infused into patients continously, for a long period of time. As a valid alternative we examined the use of mesenchymal stromal cells (MSCs) as autonomous cellular machines for the constant production of a recently described, fully humanized anti-CD33-anti-CD3 bsAb, which is capable of redirecting human T cells against CD33-expressing leukemic cells. The immortalized human MSC line SCP-1 was genetically modified into expressing bsAb at sufficient amounts to redirect T cells efficiently against CD33 presenting target cells, both in vitro and in an immunodeficient mouse model. Moreover, T cells of patients suffering from acute myeloid leukemia (AML) in blast crisis eliminated autologous leukemic cells in the presence of the bsAb secreting MSCs over time. The immune response against AML cells could be enhanced further by providing T cells an additional co-stimulus via the CD137-CD137 ligand axis through CD137L expression on MSCs. This study demonstrates that MSCs have the potential to be used as cellular production machines for bsAb-based tumor immunotherapy in the future.
Assuntos
Anticorpos Biespecíficos/biossíntese , Imunoterapia/métodos , Leucemia Mieloide Aguda/terapia , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/imunologia , Animais , Anticorpos Biespecíficos/uso terapêutico , Complexo CD3/imunologia , Linhagem Celular Tumoral , Citometria de Fluxo , Humanos , Leucemia Mieloide Aguda/imunologia , Ativação Linfocitária/imunologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Lectina 3 Semelhante a Ig de Ligação ao Ácido Siálico/imunologia , Linfócitos T/imunologia , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Owing to their clinical success, there is growing interest in novel bispecific antibodies (bsAbs) for retargeting of T cells to tumor cells including for the treatment of acute myeloid leukemia (AML). One potential target for retargeting of T cells to AML blasts is the surface molecule CD33. Here we describe a novel modular targeting platform that consists of a universal effector module (EM) and individual target modules (TMs). Both modules can form an immune complex via a peptide epitope. The resulting targeting complex can functionally replace a conventional bsAb. By fusion of a costimulatory domain (for example, the extracellular CD137 ligand domain) to the TM, the targeting complex can even provide a costimulatory signal to the redirected T cells at their side of interaction with the tumor cell. Furthermore, we observed that an efficient killing of tumor cells expressing low levels of the tumor target CD33 becomes critical at low effector-to-target cell ratios but can be improved by costimulation via CD137 using our novel targeting system.
