Aubert, N. | Search bioRxiv

bioRxiv2023

Enkephalin-mediated modulation of basal somatic sensitivity by regulatory T cells in mice

CD4+CD25+Foxp3+ regulatory T cells (Treg) have been implicated in pain modulation in various inflammatory conditions. However, whether Treg cells hamper pain at steady state and by which mechanism is still unclear. From a meta-analysis of the transcriptomes of murine Treg and conventional T cells (Tconv), we observe that the proenkephalin gene (Penk), encoding the precursor of analgesic opioid peptides, ranks among the top 25 genes most enriched in Treg cells. We then present various evidence suggesting that Penk is regulated in part by members of the TNF receptor family and the transcription factor Batf. Using mice in which the promoter activity of Penk can be tracked with a fluorescent reporter, we also show that Penk expression is mostly detected in Treg and activated Tconv in non-inflammatory conditions in the colon and skin. Functionally, Treg cells proficient or deficient for Penk suppress equally well the proliferation of effector T cells in vitro and autoimmune colitis in vivo. In contrast, inducible ablation of Penk in Treg leads to heat hyperalgesia in both male and female mice. Overall, our results indicate that Treg might play a key role at modulating basal somatic sensitivity in mice through the production of analgesic opioid peptides.

immunology↗

bioRxiv2019

HVEM blockade initiates tumor cell death by innate immunity and improves anti-tumor response by human T cells in NSG immuno-compromised mice

BackgroundTNFRSF14 (herpes virus entry mediator (HVEM) delivers a negative signal to T cells through the B and T Lymphocyte Attenuator (BTLA) molecule and has been associated with a worse prognosis in numerous malignancies. A formal demonstration that the HVEM/BTLA axis can be targeted for cancer immunotherapy is however still lacking. MethodsWe used immunodeficient NOD.SCID.gc-null mice reconstituted with human PBMC and grafted with human tumor cell lines subcutaneously. Tumor growth was compared using linear and non linear regression statistical modeling. The phenotype of tumor-infiltrating leukocytes was determined by flow cytometry. Statistical testing between groups was performed by a non-parametric t test. Quantification of mRNA in the tumor was performed using NanoString pre-designed panels. Bioinformatics analyses were performed using Metascape, Gene Set Enrichment Analysis and Ingenuity Pathways Analysis with embedded statistical testing. ResultsWe showed that a murine monoclonal antibody to human HVEM significantly impacted the growth of various HVEM-positive cancer cell lines in humanized NSG mice. Using CRISPR/cas9 mediated deletion of HVEM, we showed that HVEM expression by the tumor was necessary and sufficient to observe the therapeutic effect. Tumor cell killing by the mAb was dependent on innate immune cells still present in NSG mice, as indicated by in vivo and in vitro assays. Mechanistically, tumor control by human T cells by the mAb was dependent on CD8 T cells and was associated with an increase in the proliferation and number of tumor-infiltrating leukocytes. Accordingly, the expression of genes belonging to T cell activation pathways, such as JAK/STAT and NFKB were enriched in anti-HVEM-treated mice, whereas genes associated with immuno-suppressive pathways were decreased. Finally, we developed a simple in vivo assay to directly demonstrate that HVEM/BTLA is an immune checkpoint for T-cell mediated tumor control. ConclusionsOur results show that targeting HVEM is a promising strategy for cancer immunotherapy.

immunology↗