Characterization of TGFβ-specific CD4+T cells through the modulation of TGFβ expression in malignant myeloid cells

ABSTRACTGut resident regulatory CD4+ T (Tregs) cells in mice are mainly specific for intestinal antigens and play an important role in the suppression of immune responses against harmless dietary antigens and the gut microbiota. In contrast, information about the phenotype and function of Tregs in the human gut is limited. Here, we performed a detailed characterization of Foxp3+ CD4 Tregs in human small intestine (SI). SI Foxp3+ CD4 T cells were CD45RA-CTLA4+CD127- and suppressed proliferation of autologous T cells. Approximately 60% of SI Tregs expressed the transcription factor Helios. When stimulated, Helios- Tregs produced IL-17, IFNγ and IL-10, whereas Helios+ Tregs produced very low levels of these cytokines. Sampling mucosal tissue from transplanted human duodenum we demonstrated that donor SI Helios+ Tregs have a rapid turnover rate whereas Helios- Tregs persisted for at least 1 yr post transplantation. In the normal SI, Foxp3+ Tregs constituted only 2% of all CD4 T cells, while in active celiac disease both subsets expanded 5-10-fold. Taken together, these findings suggest that human SI contains two phenotypically and functionally distinct Treg subsets (Helios+ and Helios- Tregs), which are reminiscent of rapidly renewed dietary antigen-specific Tregs and microbiota-specific Tregs resident in the mouse gut, respectively.

Download Full-text

Integrative molecular profiling of autoreactive CD4 T cells in autoimmune hepatitis

10.1101/2020.01.06.895938 ◽

2020 ◽

Author(s):

Amédée Renand ◽

Iñaki Cervera-Marzal ◽

Laurine Gil ◽

Chuang Dong ◽

Erwan Kervagoret ◽

...

Keyword(s):

T Cells ◽

Disease Activity ◽

Autoimmune Hepatitis ◽

Peripheral Blood ◽

Cd4 T Cells ◽

Ex Vivo ◽

B Cell Differentiation ◽

Tcr Repertoire ◽

First Time

AbstractBackground & AimsIn most autoimmune disorders, crosstalk of B cells and CD4 T cells results in the accumulation of autoantibodies. In autoimmune hepatitis (AIH), the presence of anti-Soluble Liver Antigen (SLA or SepSecs) autoantibodies is associated with significantly reduced overall survival, but the associated autoreactive CD4 T cells have not been characterized yet. Here we isolated and deeply characterized SLA-specific CD4 T cells in AIH patients.MethodsWe used brief ex vivo restimulation with overlapping SLA-derived peptides to isolate and phenotype circulating SLA-specific CD4 T cells, and integrative single-cell RNA-seq (scRNA-seq) to characterize their transcriptome and TCR repertoire in n=5 AIH patients. SLA-specific CD4 T cells were tracked in peripheral blood through TCR sequencing, to identify their phenotypic niche. We further characterized disease-associated peripheral blood T cells by high content flow cytometry in an additional cohort of n=46 AIH patients and n=18 non-alcoholic steatohepatitis (NASH) controls.ResultsAutoreactive SLA-specific CD4 T cells were only detected in patients with anti-SLA autoantibodies and had a memory PD-1+CXCR5−CCR6−CD27+ phenotype. ScRNA-seq revealed their pro-inflammatory/B-Helper profile (IL21, IFNG, TIGIT, CTLA4, NR3C1, CD109, KLRB1 and CLEC2D). Autoreactive TCR clonotypes were restricted to the memory PD-1+CXCR5− CD4 T cells. This subset was significantly increased in the blood of AIH patients and supported B cell differentiation through IL-21. Finally, we identified a specific phenotype (PD-1+CD38+CD27+CD127−CXCR5−) of CD4 T cells linked to disease activity and IgG response during AIH.ConclusionsThis work provides for the first time a deep characterization of rare circulating autoreactive CD4 T cells and the identification of their peripheral reservoir in AIH. We also propose a generic phenotype of pathogenic CD4 T cells related to AIH disease activity.

Download Full-text