Gene expression comparison between the murine T-cell hybridoma 6-13-64 ICOS(-) population and ICOS(+) population
Ontology highlight
ABSTRACT: ICOS (Inducible Costimulator) is a T cell costimulatory molecule. We found that the cloned T-cell hybridoma 6-13-64 consists of two populations, ICOS expressing and non-expressing. The aim of this study is to screen for candidate genes that regulate ICOS gene expression by transcriptional profiling and comparison of the ICOS-positive and ICOS-negative subpopulations isolated from the 6-13-64 T-cell hybridoma. One-condition experiment, ICOS(-) vs. ICOS(+) cells. Independently grown and harvested. One replicate per array.
Project description:ICOS (Inducible Costimulator) is a T cell costimulatory molecule. We found that the cloned T-cell hybridoma 6-13-64 consists of two populations, ICOS expressing and non-expressing. The aim of this study is to screen for candidate genes that regulate ICOS gene expression by transcriptional profiling and comparison of the ICOS-positive and ICOS-negative subpopulations isolated from the 6-13-64 T-cell hybridoma.
Project description:The role of ICOS in anti-tumor T cell responses and overall tumor progression has been controversial. Here, we compared tumor progression in mice lacking ICOS only in Treg cells or in all T cells. We found that Treg-specific ICOS knockout reduces the overall tumor burden compared to Cre control mice with increased T effector/Treg ratios in the tumor. In contrast, there was no difference in the tumor burden in mice lacking ICOS in all the T cell compartments. This suggests a dual role of ICOS costimulation in promoting pro- and anti-tumor T cell responses. Consistent with reduced tumor burden, we found that Treg-specific deletion of ICOS leads to an increase of CD8+ CTLs that express high levels of granzyme B and perforin. Moreover, single-cell transcriptome analysis revealed an increase of Ly108hiEomeshi CD8+ T cell subset at the cost of Ly108hiT-bethi subset in Treg-specific knockout mice. These results suggest that ICOS-expressing Treg cells suppress CTL maturation process at the level of Eomes upregulation, a critical step known to drive perforin expression and cytotoxicity. Collectively, our data imply that cancer immunotherapies using ICOS agonist antibodies would work better in Treg-low tumors or when they are combined with regimens that deplete tumor-infiltrating Treg cells.
Project description:Mucin 1 (MUC1) is a transmembrane mucin expressed at the apical surface of epithelial cells at different mucosal surfaces including breast and intestine. The MUC1 extracellular domain contains a variable number of tandem repeats (VNTR) of 20 amino acids, which are heavily O-linked glycosylated. Monoclonal antibodies against the MUC1 VNTR can be powerful tools because of their multiplicity of binding and possible applications in the diagnosis and treatment of MUC1-expressing cancers. One such antibody is the hybridoma mouse monoclonal 139H2 which is also widely used as a research tool to study non-cancer MUC1. Here we report direct mass spectrometry-based sequencing of hybridoma-derived 139H2 IgG, which enabled reverse engineering of a recombinant 139H2.
Project description:ICOS is a T cell costimulatory receptor critical for Tfh cell generation and function. However, the role of ICOS in Tfr cell differentiation remains unclear. Using Foxp3-Cre-mediated ICOS knockout (ICOS FC) mice, we show that ICOS deficiency in Treg-lineage cells drastically reduces the number of Tfr cells during GC reactions but has a minimal impact on conventional Treg cells. Single-cell transcriptome analysis of Foxp3+ cells at an early stage of the GC reaction suggests that ICOS normally inhibits Klf2 expression to promote follicular features including Bcl6 upregulation. Further, ICOS costimulation promotes nuclear localization of NFAT2, a known driver of CXCR5 expression. Notably, ICOS FC mice had an unaltered overall GC B cell output but showed signs of expanded autoreactive B cells along with elevated autoantibody titers. Thus, our study demonstrates that ICOS costimulation is critical for Tfr cell differentiation and highlights the importance of Tfr cells in maintaining humoral immune tolerance during GC reactions.
Project description:ICOS is induced in activated T cells and its main role is to boost differentiation and function of effector T cells. ICOS is also constitutively expressed in a subpopulation of Foxp3+ regulatory T cells under steady-state condition. Studies using ICOS germline knockout mice or ICOS-blocking reagents suggested that ICOS has supportive roles in regulatory T (Treg) cell homeostasis, migration, and function. To avoid any compounding effects that may arise from ICOS-deficient non-Treg cells, we generated a conditional knockout system in which ICOS expression is selectively abrogated in Foxp3-expressing cells (ICOS FC mice). Compared to Foxp3-Cre control mice, ICOS FC mice showed a minor numerical deficit of steady-state Treg cells but did not show any signs of spontaneous autoimmunity, indicating that tissue-protective Treg populations do not heavily rely on ICOS costimulation. However, ICOS FC mice showed more severe inflammation in oxazolone-induced contact hypersensitivity, a model of atopic dermatitis. This correlated with elevated numbers of inflammatory T cells expressing IFN-γ and/or TNF-α in ICOS FC mice compared with the control group. In contrast, elimination of ICOS in all T cell compartments negated the differences, confirming that ICOS has a dual positive role in effector and Treg cells. Single-cell transcriptome analysis suggested that ICOS-deficient Treg cells fail to mature into T-bet+CXCR3+ “Th1-Treg” cells in the draining lymph node. Our results suggest that regimens that preferentially stimulate ICOS pathways in Treg cells might be beneficial for the treatment of Th1-driven inflammation.
Project description:The maintenance of the TFH phenotype depends on continuous signals via ICOS. For a global assessment of differences in gene expression after interruption of the ICOS pathway a genome wide transcriptome analysis was performed. We used the OT-II adoptive transfer system to isolate antigen-specific TFH cells (day 6 after immunization) after short-term (6 hours) blockade of the ICOS pathway using a monoclonal antibody against ICOS-L. Gene expression profiles of TFH cells with or without ICOS-L blockade. Affymetrix MG 430 2.0 whole genome arrays were performed in duplicates for the control and blockade group (4 arrays in total). To obtain genes significantly regulated upon ICOS L blockade, the expression profiles of TFH cells treated with an isotype control or anti-ICOS-L antibody were compared to each other. After total RNA extraction, reverse transcription, cDNA extraction, the biotinylated cRNA was transcribed, fragmented, and 15 M-BM-5g cRNA hybridized in duplicates for each of the two groups to the 4 GeneChip arrays: Group1 TFH cells control, Group2 TFH cells ICOS-L blockade.
Project description:Investigation of whole genome gene expression level changes in Mus musculus 3B4.15 T hybridoma cells treated with 1microMolar Dexamethasone compared to mock treated cells. Interleukin-7 receptor alpha (IL-7Rα) is essential for T cell survival and differentiation. Glucocorticoids are potent enhancers of IL-7Rα expression with diverse roles in T cell biology. Here we identify the transcriptional repressor, Growth factor independent-1 (Gfi1), as a novel intermediary in glucocorticoid-induced IL-7Rα upregulation. We found Gfi1 to be a major inhibitory target of dexamethasone by microarray expression profiling of 3B4.15 T-hybridoma cells. Concordantly, retroviral transduction of Gfi1 significantly blunted IL-7Rα upregulation by dexamethasone. To further assess the role of Gfi1 in vivo, we generated bacterial artificial chromosome (BAC) transgenic mice, in which a modified Il7r locus expresses GFP to report Il7r gene transcription. By introducing this BAC reporter transgene into either Gfi1-deficient or Gfi1-transgenic mice, we document in vivo that IL-7Rα transcription is upregulated in the absence of Gfi1 and downregulated when Gfi1 is overexpressed. Strikingly, the in vivo regulatory role of Gfi1 was specific for CD8+, and not CD4+ T cells or immature thymocytes. These results identify Gfi1 as a specific transcriptional repressor of the Il7r gene in CD8 T lymphocytes in vivo.