Enforced IL-10 Expression Confers Type 1 Regulatory T Cell (Tr1) Phenotype and Function to Human CD4+ T Cells

Abstract

Type 1 regulatory T (Tr1) cells are an inducible subset of CD4 + Tr cells characterized by high levels of interleukin (IL)-10 production and regulatory properties. Several protocols to generate human Tr1 cells have been developed in vitro. However, the resulting population includes a significant fraction of contaminating non-Tr1 cells, representing a major bottleneck for clinical application of Tr1 cell therapy. We generated an homogeneous IL-10-producing Tr1 cell population by transducing human CD4 + T cells with a bidirectional lentiviral vector (LV) encoding for human IL-10 and the marker gene, green fluorescent protein (GFP), which are independently coexpressed. The resulting GFP + LV-IL-10-transduced human CD4 + T (CD4 LV-IL-10 ) cells expressed, upon T-cell receptor (TCR) activation, high levels of IL-10 and concomitant low levels of IL-4, and markers associated with IL-10. Moreover, CD4 LV-IL-10 T cells displayed typical Tr1 features: the anergic phenotype, the IL-10, and transforming growth factor (TGF)-dependent suppression of allogeneic T-cell responses, and the ability to suppress in a cell-to-cell contact independent manner in vitro. CD4 LV-IL-10 T cells were able to control xeno graft-versus-host disease (GvHD), demonstrating their suppressive function in vivo. These results show that constitutive over-expression of IL-10 in human CD4 + T cells leads to a stable cell population that recapitulates the phenotype and function of Tr1 cells.

Alterations in the Cellular Immune Compartment of Patients Treated with Third-Party Mesenchymal Stromal Cells Following Allogeneic Hematopoietic Stem Cell Transplantation

“…In addition to the naturally occurring T reg -cells, MSCs promote the induction of IL-10 þ Tr1-cells [14]. In animal models, Tr1-cells control GVHD by promoting long-term tolerance [40]. Patients treated with MSCs had increased levels of Tr1-cells on dþ30 and dþ90, similarly to the naturally occurring T reg -cell kinetics (Fig.…”

Interleukin-10 Gene-Modified Dendritic Cell-Induced Type 1 Regulatory T Cells Induce Transplant-Tolerance and Impede Graft Versus Host Disease After Allogeneic Stem Cell Transplantation

“…The harvested were then resuspended in RPMI-1640 medium containing 10% FBS and 1% penicillin/streptomycin and adjusted to suitable cell concentrations. Recipient mice (BALB/c) were given a lethal dose of radiation (8 Gy) [18] and then intravenously transplanted with donor BMCs (1 × 10 7 ) and SCs (4 × 10 7 ) [19]. The recipients were randomly assigned to the following groups based on their number of injected Tr1 cells; control group: BM + T; BM + T + Tr1 cells (2 × 10 6 ); BM + T + Tr1 cells (4 × 10 6 ).…”

“…As an alternative method for obtaining a large and homogeneous population of Tr1 cells, lentivirus-mediated human IL-10 gene transfer has been used to convert conventional T cells into Tr1-like cells, which mirror the phenotype and function of Tr1 cells, and can suppress or prevent transplant rejection and GVHD. However, an important limitation of this method is that the generated Tr1-like cells cannot acquire autoantigen specificity [18]. …”

Type 1 regulatory T cells: a new mechanism of peripheral immune tolerance

“…39 Purified CD4 LV-IL-10 T cells were cultured in an allogeneic feeder cell system containing irradiated PBMCs (10 6 /ml), irradiated JY cells (10 5 /ml), and soluble anti-CD3 monoclonal antibodies (1 mg/ml). After 12 days of culture, CD4…”