Cancer immunotherapy employs components of a persons’ immune system to fight cancer. Some of these therapies rely on Dendritic Cells (DCs), specialized in the recognition, processing and presentation of antigens to the effector cells of the immune system. Usually DC-precursors are obtained from each patient and cultured before re-administration. However, limited number or immature cells are generated using these approaches. Additionally, DC-precursors are already compromised in some cancer patients. Direct cell reprogramming offers an exciting alternative to overcome these limitations: the identity of a cell can be modified into another cell-type using lineage instructive transcription factors (TFs). Reprogramming from unrelated cell-types, not affected by cancer, represent a therapeutically attractive source of DCs to elicit adaptive immune responses.
We aim to identify DC-inducing TFs in mouse fibroblasts harboring a DC-specific fluorescent reporter. This analysis will be complemented by immunophenotipic characterization and assessment of cell fate stability. Reprogrammed DC transcriptional profile will be extensively characterized in order to confer their similarity with “natural” DCs. We will also assess the functional proprieties of DCs using both in vitro and in vivo assays by evaluating their capacity to activate antigen-specific T-cells. We will also assess whether the identified combination of TFs can reprogram skin dermal fibroblasts into DCs. Their ability to efficiently present antigens to effector cells and to mount an immune response against pediatric Acute Myeloid Leukemia (AML) cancer cells will be tested.
Key experimental approaches will include molecular cloning, flow cytometry, high-content automated image acquisition and analysis, gene expression profiling, cellular transplantation and Crispr/Cas9 gene editing. Collectively this work will provide thorough insight into DC transcriptional networks. This knowledge will be applied for patient-specific DC generation. Ultimately, this project will represent a pioneering contribution for applying direct reprogramming to generate novel DC-based immunotherapies for AML and other aggressive pediatric cancers.
Cell Reprogramming in Hematopoiesis and Immunity lab
Cellular reprogramming can be achieved experimentally in different ways, including nuclear transfer, cell fusion or expression of transcription factors. We aim to uncover how hematopoietic stem cell and effector cell identity is established employing cellular reprogramming logic. Ultimately our work may allow the generation of patient-specific hematopoietic cells for regenerative medicine and immunotherapy.
Rosa & Pires et al. Direct reprogramming of fibroblasts into antigen-presenting dendritic cells. Science Immunology, featured in the cover of December issue 2018.