title: Efficient generation of human alloantigen-specific CD4+ regulatory T cells from naive precursors by CD40-activated B cells.
abstract: CD4(+)CD25(+)Foxp3(+) regulatory T cells (Treg) play an important role in the induction and maintenance of immune tolerance. Although adoptive transfer of bulk populations of Treg can prevent or treat T cell-mediated inflammatory diseases and transplant allograft rejection in animal models, optimal Treg immunotherapy in humans would ideally use antigen-specific rather than polyclonal Treg for greater specificity of regulation and avoidance of general suppression. However, no robust approaches have been reported for the generation of human antigen-specific Treg at a practical scale for clinical use. Here, we report a simple and cost-effective novel method to rapidly induce and expand large numbers of functional human alloantigen-specific Treg from antigenically naive precursors in vitro using allogeneic nontransformed B cells as stimulators. By this approach naive CD4(+)CD25(-) T cells could be expanded 8-fold into alloantigen-specific Treg after 3 weeks of culture without any exogenous cytokines. The induced alloantigen-specific Treg were CD45RO(+)CCR7(-) memory cells, and had a CD4(high), CD25(+), Foxp3(+), and CD62L (L-selectin)(+) phenotype. Although these CD4(high)CD25(+)Foxp3(+) alloantigen-specific Treg had no cytotoxic capacity, their suppressive function was cell-cell contact dependent and partially relied on cytotoxic T lymphocyte antigen-4 expression. This approach may accelerate the clinical application of Treg-based immunotherapy in transplantation and autoimmune diseases.
authors.affiliation: Department of Paediatrics and Adolescent Medicine, Li Ka Shing Faculty of Medicine, University of Hong Kong, Hong Kong SAR, PR China. wwtu@hkucc.hku.hk
authors.forename: Wenwei
authors.initials: W
authors.lastname: Tu
authors.forename: Yu-Lung
authors.initials: YL
authors.lastname: Lau
authors.forename: Jian
authors.initials: J
authors.lastname: Zheng
authors.forename: Yinping
authors.initials: Y
authors.lastname: Liu
authors.forename: Ping-Lung
authors.initials: PL
authors.lastname: Chan
authors.forename: Huawei
authors.initials: H
authors.lastname: Mao
authors.forename: Kira
authors.initials: K
authors.lastname: Dionis
authors.forename: Pascal
authors.initials: P
authors.lastname: Schneider
authors.forename: David B
authors.initials: DB
authors.lastname: Lewis
mesh_terms: D017951:Antigen Presentation; D001402:B-Lymphocytes / Q000166:cytology / Q000276:immunology*; D019013:CD40 Antigens; D002450:Cell Communication / Q000276:immunology; D018929:Cell Culture Techniques / Q000191:economics / Q000379:methods; D018920:Coculture Techniques; D006801:Humans; D016130:Immunophenotyping; D007519:Isoantigens / Q000276:immunology*; D008722:Methods; D037182:T-Cell Antigen Receptor Specificity; D050378:T-Lymphocytes, Regulatory / Q000166:cytology / Q000276:immunology*
chemical_list: D019013:CD40 Antigens; D007519:Isoantigens