title: Delta-like 1-mediated Notch signaling enhances the in vitro conversion of human memory CD4 T cells into FOXP3-expressing regulatory T cells.
abstract: FOXP3-expressing regulatory T cells (Treg) are essential for the prevention of autoimmunity and were shown to be reduced and/or dysfunctional in several autoimmune diseases. Although Treg-based adoptive transfer represents a promising therapy, the large cell number required to achieve clinical efficacy constitutes an important limitation. Therefore, novel strategies to generate bona fide in vitro-induced Treg (iTreg) are critical. In this study, we report that human memory CD4 T cells can be efficiently converted into iTreg, and that Delta-like 1 (DL1)-mediated Notch signaling significantly enhances this process. The iTreg generated in the presence of DL1 featured higher levels of Treg function-associated molecules and were efficient suppressors. Importantly, these iTreg displayed a stable phenotype in long-term cultures, even in the presence of proinflammatory cytokines. Additionally, DL1 potentiated FOXP3 acquisition by memory CD4 cells through the modulation of the TGF-β signaling pathway and of Foxp3 transcription. Our data demonstrate that iTreg can be efficiently induced from memory CD4 cells, a subset enriched in relevant specificities for targeting in autoimmune diseases, and that DL1 enhances this process. DL1 also enhanced the proliferation and Treg function-associated marker expression of ex vivo-stimulated human circulating FOXP3(+) cells. Manipulation of the Notch signaling pathway constitutes a promising approach to boost the in vitro generation of iTreg and ex vivo Treg expansion, thus facilitating the establishment of effective Treg-based adoptive therapy in autoimmune diseases.
authors.affiliation: Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, 1649-028 Lisbon, Portugal; and Hospital Universitário de Santa Maria, Centro Hospitalar Lisboa Norte, 1649-035 Lisbon, Portugal.
authors.forename: Catarina
authors.initials: C
authors.lastname: Mota
authors.affiliation: Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, 1649-028 Lisbon, Portugal; and.
authors.forename: Vânia
authors.initials: V
authors.lastname: Nunes-Silva
authors.affiliation: Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, 1649-028 Lisbon, Portugal; and.
authors.forename: Ana R
authors.initials: AR
authors.lastname: Pires
authors.affiliation: Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, 1649-028 Lisbon, Portugal; and.
authors.forename: Paula
authors.initials: P
authors.lastname: Matoso
authors.affiliation: Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, 1649-028 Lisbon, Portugal; and Hospital Universitário de Santa Maria, Centro Hospitalar Lisboa Norte, 1649-035 Lisbon, Portugal.
authors.forename: Rui M M
authors.initials: RM
authors.lastname: Victorino
authors.affiliation: Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, 1649-028 Lisbon, Portugal; and.
authors.forename: Ana E
authors.initials: AE
authors.lastname: Sousa
authors.affiliation: Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, 1649-028 Lisbon, Portugal; and iriscaramalho@fm.ul.pt.
authors.forename: Iris
authors.initials: I
authors.lastname: Caramalho
mesh_terms: D000954:Antigens, Surface / Q000378:metabolism; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology* / Q000378:metabolism*; D002135:Calcium-Binding Proteins; D065150:Cellular Reprogramming / Q000276:immunology; D051858:Forkhead Transcription Factors / Q000378:metabolism; D006801:Humans; D007156:Immunologic Memory; D016130:Immunophenotyping; D036341:Intercellular Signaling Peptides and Proteins / Q000378:metabolism*; D008565:Membrane Proteins / Q000378:metabolism*; D010641:Phenotype; D051880:Receptors, Notch / Q000378:metabolism*; D015398:Signal Transduction; D050378:T-Lymphocytes, Regulatory / Q000276:immunology* / Q000378:metabolism*
chemical_list: D000954:Antigens, Surface; D002135:Calcium-Binding Proteins; C512941:DLK1 protein, human; C418974:FOXP3 protein, human; D051858:Forkhead Transcription Factors; D036341:Intercellular Signaling Peptides and Proteins; D008565:Membrane Proteins; D051880:Receptors, Notch