Project description:Gene-edited rats were generated in which EGFP was placed under the transcriptional control of the Foxp3 promoter. EGFP expression by CD4+ and CD8+ T cells allowed to define regulatory T cells (Treg) in both T cell compartments. This Foxp3-EGFP rats constitute a useful model to identify CD4+ and CD8+ natural and induced Treg. Transcriptomic analyses showed similarities but also differences among CD4+ and CD8+ EGFP+ cells, this being the first description of the transcriptomic profile in natural FOXP3+ CD8+ Treg.
Project description:Adoptive natural regulatory T cell (nTreg) therapy has improved the outcome for patients suffering from graft-versus-host disease (GVHD) following allogeneic hematopoietic cell transplantation (allo-HCT). However, fear of broad immune suppression and subsequent dampening of beneficial graft-versus-leukemic (GVL) responses remains a challenge. To address this concern, we generated alloreactive induced Tregs (iTregs) from resting CD4 or CD8 T cells and tested their ability to suppress GVH and maintain GVL responses. We utilized major mismatched and haploidentical murine models of HCT with host-derived lymphoma or leukemia cell lines to evaluate GVH and GVL responses simultaneously. Alloreactive CD4 iTregs were effective in preventing GVHD, but abrogated the GVL effect against aggressive leukemia. Alloreactive CD8 iTregs moderately attenuated GVHD while sparing the GVL effect. Hence, we reasoned that using a combination of CD4 and CD8 iTregs could achieve the optimal goal of allo-HCT. Indeed, the combinational therapy was superior to CD4 or CD8 iTreg singular therapy in GVHD control; importantly, the combinational therapy maintained GVL responses. Cellular analysis uncovered potent suppression of both CD4 and CD8 effector T cells by the combinational therapy that resulted in effective prevention of GVHD, which could not be achieved by either singular therapy. Gene expression profiles revealed alloreactive CD8 iTregs possess elevated expression of multiple cytolytic molecules compared to CD4 iTregs, which likely contributes to GVL preservation. Our study uncovers unique differences between alloreactive CD4 and CD8 iTregs that can be harnessed to create an optimal iTreg therapy for GVHD prevention with maintained GVL responses.
Project description:Transcription profiling of mouse CD4+ and CD8+ T cells extracted from GFP-Egr2 knockin (Egr2 Kin) and hCD2-Cre / Egr2loxP/loxP / Egr3-/- Egr2/3 DKO) mice 7 days after infection with vaccinia virus.
Project description:Though T cell expansion and effector differentiation are triggered and, perhaps, maintained by antigen, the proliferative behaviors of CD4+ and CD8+ T cells responding to timed antigen presentation have rarely been compared side by side. Proliferation and effector differentiation of TCR transgenic and polyclonal T cells were analyzed following transient and continuous TCR signals. We found CD4+ T cell proliferation to be dependent on prolonged antigen presence, whereas CD8+ T cells were able to divide and differentiate into effector cells in the absence of it. We excluded CD4+ T cell proliferation to be abrogated by coinhibitory signals or the lack of inflammatory stimuli and found that autonomous proliferation of CD8* T cells was independent of any MHC class I signals. Gene expression analyses illustrated differences in global gene transcription between the two subsets following stimulation periods of different lengths. These T cell data reflect the MHC class difference in that class II but not class I molecules were stabilized on activated DCs in vivo, suggesting a coevolution of MHC molecules and their respective T cell subsets. Samples 1-12: Analysis on day 2. Purified CD4+ AND-TCR transgenic cells and CD8+ OT1-TCR transgenic cells were separately stimulated with anti-CD3 and anti-CD28 antibodies. 48 hours later, the cells were sorted again to a purity of >99 %. Extracted total RNA was amplified twice and hybridized on Affymetrix Mouse 430A2 microarrays. First, we analysed the changes of the CD4+ and CD8+ T cells after stimulation. Second, we compared the differences of the changes between the two cell types after stimulation. For each of the four groups (CD4+ and CD8+, stimulated and unstimulated), we analysed three independent biological replicates. Samples 13-28: Analysis on day 5. AND and OT1 TCR-transgenic T cells were prepared as described before, but transferred into mice that do not or do present their respective antigens. 72 hours later, the cells were FACS-sorted twice to >99 % purity, directly into Trizol. For each of the six groups (CD4+ and CD8+, unstimulated, transient (2 days) and continuous (5 days) stimulation), three independent biological replicates were analyzed, except for CD4+ unstimulated and CD4+ transient, with two replicates each.