Dataset Information

Interleukin-18 and cytotoxic impairment are independent and synergistic causes virus-induced hyperinflammation in mice

ABSTRACT: To determine the effects of excess IL-18 on virus-induced immunopathology, we infected Il18-transgenic (Il18tg) mice with Lymphocytic Choriomeningitis Virus (LCMV, Armstrong). LCMV infection is self-limited in wild-type (WT) mice, but Prf1-/- mice develop prolonged viremia and fatal HLH. LCMV-infected Il18-transgenic (Il18tg) mice developed cachexia and hyperinflammation comparable to Prf1-/- mice, albeit with minimal mortality. We use RNA-sequencing to identify differences in the transcriptome of GP33 - specific CD8 T cells from these mice in comparison to a wild type mouse under the same conditions. We saw expression of Ifng was elevated about 4-fold in both Prf1-/- and Il18tg mice. Genes specifically upregulated in Il18tg CD8 T-cells included Csf2, Il1rl1, and Il12rb2. We also saw differences between Prf1-/- and WT/Il18tg CD8 T-cells that included Klrg1 and transcripts associated with CD8 T-cell exhaustion, including the inhibitory receptors Lag3, Havcr2, and Tigit, and the transcription factors Tox and Prdm1. These data support that IL-18 as a potent, independent, and modifiable driver of life-threatening innate and adaptive hyperinflammation, and support the rationale for an IL-18-driven subclass of hyperinflammation.

ORGANISM(S): Mus musculus

PROVIDER: GSE150077 | GEO | 2020/11/12

REPOSITORIES: GEO

ACCESS DATA

Similar Datasets

Project description:In chronic infections and cancer, exhausted CD8 T cells exhibit heterogeneous subpopulations. TCF1+PD-1+ progenitor exhausted CD8 T cells (Tpex) can self-renew and give rise to Tim-3+PD-1+ terminally differentiated CD8 T cells that retain their effector functions. Tpex cells are thus essential to maintaining a pool of antigen-specific CD8 T cells during persistent antigenic stimulation, and only they respond to PD-1-targeted therapy. Despite their potential as a crucial therapeutic target for immune interventions, the mechanisms controlling the maintenance of virus-specific Tpex cells remain to be determined. We observed approximately 10-fold fewer Tpex cells in the spleens of mice chronically infected with lymphocytic choriomeningitis virus (LCMV) one-year post-infection (p.i.) than at three months p.i. Similar to memory CD8 T cells, Tpex cells have been found to undergo self-renewal in the lymphoid organs, prominently the bone marrow, during chronic LCMV infection. Furthermore, ex vivo treatment with IL-15 preferentially induced the proliferation of Tpex cells rather than the terminally differentiated subsets. Interestingly, single-cell RNA sequencing analysis of LCMV-specific exhausted CD8 T cells after ex vivo IL-15 treatment compared with those before treatment revealed upregulation of ribosome-related genes and downregulation of genes associated with the TCR signaling pathway and apoptosis in both Tpex and Ttex subsets. The exogenous administration of IL-15 to chronically LCMV-infected mice also significantly increased self-renewal of Tpex cells in the spleen and bone marrow. In addition, we assessed the responsiveness of CD8 tumor-infiltrating lymphocytes (TILs) from renal cell carcinoma patients to IL-15. Similar to the data we obtained from chronic viral infection in mice, the expansion of the Tpex subset of PD-1+ CD8 TILs upon ex vivo IL-15 treatment was significantly higher than that of the terminally differentiated subset. These results show that IL-15 could promote self-renewal of Tpex cells, which has important therapeutic implications.

Project description:Metabolic and nutrient-sensing pathways play an important role in controlling the efficacy of effector T cells. Oxygen is a critical regulator of cellular metabolism. However, during immune responses T cells must function in oxygen-deficient, or hypoxic, environments. Here, we used high resolution mass spectrometry to investigate how hypoxia configures the proteome of CD8+ cytotoxic T lymphocytes (CTLs). We identified and quantified over 7,600 proteins and discovered that hypoxia increased the abundance of a selected number of proteins in CTLs. This included glucose transporters, metabolic enzymes, transcription factors, cytolytic effector molecules, checkpoint receptors and adhesion molecules. While some of these proteins may augment the effector functions of CTLs, others may limit their cytotoxicity. These data provide a comprehensive resource for understanding the magnitude of the CTL response to hypoxia and emphasise the importance of oxygen-sensing pathways for controlling CD8+ T cells. Additionally, this study provides new understanding about how hypoxia may promote the effector function of CTLs, while contributing to their dysfunction in some contexts. For this project, P14 cytotoxic T cells (CTLs) were generated from T cells from the spleens of mice. CD8+ T cells were activated for 2 days with the P14-T cell receptor (TCR) cognate ligand (peptide gp33-41 from Lymphocytic Choriomeningitis Virus, LCMV) in the presence of 20 ng/ml IL 2 (Proleukin) and 2 ng/ml IL-12 (Peprotech). Cells were grown in a humidified incubator with a gas atmosphere of 18% oxygen and 5% CO2 and a temperature of 37�C. After 48 hours, the activated CD8+ T cells were removed from TCR stimulation and were cultured in RPMI 1640, with 10% foetal bovine serum (FBS), supplemented with 100 units/ml penicillin-G, 100 �g/ml streptomycin, 50 �M-mercaptoethanol and 20 ng/ml IL-2 (Proleukin). Each day, the T cells were counted and split to 500,000 cells per ml with fresh IL-2 being added to a final concentration of 20 ng/ml. CTLs were differentiated in IL-2 for 4 days, before being counted and re-suspended at a concentration of 300,000 cells per ml in RPMI with 10% foetal bovine serum, 50 units/ml penicillin-G, 50 �g/ml streptomycin, 50 �M-mercaptoethanol and 20 ng/ml IL-2. A volume of 8 mls of the cell suspension was plated per well of a 6 well plate, and the CTLs were either maintained in a gas atmosphere of 18% oxygen and 5% CO2 or transferred to an atmosphere of 1% O2 and 5% CO2 in a Galaxy 48 R incubator (Eppendorf) for 24 hours. Three biological replicates (CTLs generated from three separate spleens) were analysed in this experiment."

Dataset Information

Interleukin-18 and cytotoxic impairment are independent and synergistic causes virus-induced hyperinflammation in mice

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure