Project description:Mast cells are indispensable for LPS-induced septic hypothermia, in which TNF-α plays an essential role to initiate sepsis. Tec family non-receptor tyrosine kinases ITK and BTK regulate mast cell-derived TNF-α in response to allergic antigen, but their role in LPS-induced TNF-α production by mast cells and related pathology is unclear. We sought to investigate the role(s) of ITK and BTK in mast cell response in septic condition. We found that the absence of ITK and BTK leads to enhanced TNF-α production by bone marrow-derived mast cells (BMMC). Itk-/-Btk-/- mast cells exhibit hyperactive preformed and LPS-induced TNF-α production, along with enhanced expression of other related genes such as NF-κB targeted genes, compared to WT cells. Bone marrow cells from 8-week old WT, Itk-/-, Btk-/- and Itk-/-Btk-/- (double knockout: DKO) C57Bl/6 mice were cultured in murine Interleukin-3/Stem cell factor (IL-3/SCF) supplemented medium for 5 weeks to derive mast cells. WT, Itk-/-, Btk-/- and DKO bone marrow-derived mast cells (BMMC) were factor starved in medium without IL-3/SCF for 12 hours, followed by treatment with PBS (control) or 100 ng/ml LPS for 1 hour. Triplicates of each group were subjected to mouse whole genome genechip microarray analysis. Replicates were randomized on different chips to avoid systematic error.
Project description:Mast cells are indispensable for LPS-induced septic hypothermia, in which TNF-α plays an essential role to initiate sepsis. Tec family non-receptor tyrosine kinases ITK and BTK regulate mast cell-derived TNF-α in response to allergic antigen, but their role in LPS-induced TNF-α production by mast cells and related pathology is unclear. We sought to investigate the role(s) of ITK and BTK in mast cell response in septic condition. We found that the absence of ITK and BTK leads to enhanced TNF-α production by bone marrow-derived mast cells (BMMC). Itk-/-Btk-/- mast cells exhibit hyperactive preformed and LPS-induced TNF-α production, along with enhanced expression of other related genes such as NF-κB targeted genes, compared to WT cells.
Project description:IL-2 inducible tyrosine kinase (Itk) is a Tec family non-receptor tyrosine kinase that is known to regulate T-helper cell differentiation and function. It has been established that Itk postively regulates T helper 17 cells. However, in a model of hypersensitivity pneumonitis we found T helper 17 cells develop independently of Itk. Therefore, we compared the transcriptomes of WT and Itk-/- T helper 17 cells following exposure with Saccharopolyspora rectivirgula by RNA sequencing.
Project description:IL-2-inducible T cell kinase (ITK) is essential for T cell receptor (TCR) signaling and plays an integral role in T-cell proliferation and differentiation. Unlike the ITK homolog BTK, no inhibitors of ITK are currently FDA approved. In addition, recent studies have identified mutations within BTK that confer resistance to both covalent and non- covalent inhibitors. Here, as an alternative strategy, we report the development of BSJ-05-037, a potent and selective heterobifunctional degrader of ITK. BSJ-05-037 displayed enhanced anti-proliferative effects relative to its parent inhibitor BMS- 509744, blocked the activation of NF-kB/GATA-3 signaling and increased the sensitivity of T cell lymphoma cells to cytotoxic chemotherapy both in vitro and in vivo. In summary, targeted degradation of ITK is a novel approach to modulate TCR signal strength that could have broad application for the investigation and treatment of T cell-mediated diseases.
Project description:IL-2-inducible T cell kinase (ITK) is essential for T cell receptor (TCR) signaling and plays an integral role in T-cell proliferation and differentiation. Unlike the ITK homolog BTK, no inhibitors of ITK are currently FDA approved. In addition, recent studies have identified mutations within BTK that confer resistance to both covalent and non-covalent inhibitors. Here, as an alternative strategy, we report the development of BSJ-05-037, a potent and selective heterobifunctional degrader of ITK. BSJ-05-037 displayed enhanced anti-proliferative effects relative to its parent catalytic inhibitor, blocked the activation of NF-kB/GATA-3 signaling and increased the sensitivity of T cell lymphoma cells to cytotoxic chemotherapy both in vitro and in vivo. In summary, targeted degradation of ITK is a novel approach to modulate TCR signal strength that could have broad application for the investigation and treatment of T cell-mediated diseases.
Project description:IL-2 inducible tyrosine kinase (Itk) is a Tec family non-receptor tyrosine kinase that is known to regulate T cell receptor signal strength (TcR) and T cell development and differentiation. TcR signal strength and antigen affinity are parameters known to regulate the development of CD8+ T cell memory. However, the intersection between TcR signal strength and antigen affinity on CD8+ memory T cell development remains unclear. Therefore, we compared the transcriptomes of WT and Itk-/- OT-1/Rag-/- CD8+ T cells at day 0 and day 7 following infection with Listeria monocytogenes expressing the SIINFEKL (N4) or SIITFEKL (T4) OVA peptide variant (different affinities for TcR) by RNA sequencing.
Project description:We analyzed gene expression profiles of unstimulated Herpesvirus Saimiri (HVS) transformed T cells (CD4+) of patients harboring a homozygous R335W mutation in the IL-2 inducible T cell kinase (ITK) compared to healthy control HVS cells. We identified a set of 1927 Affymetrix probe sets showing significant misregulation in the ITK deficient cells (Welch's T-test, p<0.05). HVS T cell lines (ITK wt or ITK R335W, each CD4+) from three independent culturing time points were used for RNA extraction and hybridization on Affymetrix microarrays.
Project description:We analyzed gene expression profiles of unstimulated Herpesvirus Saimiri (HVS) transformed T cells (CD4+) of patients harboring a homozygous R335W mutation in the IL-2 inducible T cell kinase (ITK) compared to healthy control HVS cells. We identified a set of 1927 Affymetrix probe sets showing significant misregulation in the ITK deficient cells (Welch's T-test, p<0.05).
Project description:Splenic Transitional Type-1 B-cells from CBA wild-type mice, X-linked immunodeficiency mice and Bruton's tyrosine kinase knock-out mice. Two replicates where run on Affymetrix 420 2.0 arrays for CBA wild-type, Xid samples and the Btk KO samples. Bruton's tyrosine kinase (Btk) is a cytoplasmic tyrosine kinase important for B-lymphocyte maturation. Mutations in Btk give rise to the primary immunodeficiency disease X-linked agammaglobulinemia (XLA) in man and X-linked immunodeficiency (Xid) in mice. Recent studies have subdivided the mouse immature, or transitional, B-cells into two distinct subsets according to their respective surface markers. Transitional type 1 (T1) and transitional type 2 (T2) cells are also located in distinct anatomic locations. Based on a limited number of markers it has previously been reported that the earliest phenotypic sign of Btk deficiency is manifested at the T2 stage in mice. Here, we report on distinct genome-wide transcriptomic signature differences found in T1 B-lymphocytes from Btk-defective compared to normal mice and demonstrate that Btk deficiency is visible already at this stage. 2 replicates of T1 B-cells from CBA (WT), Xid samples and the Btk KO samples
Project description:The Tec-family kinase Itk plays an important role during T-cell activation and function, and controls also conventional versus innate-like T-cell development. We have characterized the transcriptome of Itk-deficient CD3+ T-cells, including CD4+ and CD8+ subsets, using Affymetrix microarrays. The largest difference between Itk-/- and Wt CD3+ T-cells was found in unstimulated cells, e.g. for killer cell lectin-like receptors. Compared to anti-CD3-stimulation, anti-CD3/CD28 significantly decreased the number of transcripts suggesting that the CD28 co-stimulatory pathway is mainly independent of Itk. The signatures of CD4+ and CD8+ T-cell subsets identified a greater differential expression than in total CD3+ cells. Cyclosporin (CsA)-treatment had a stronger effect on transcriptional regulation than Itk-deficiency, suggesting that only a fraction of TCR-mediated calcineurin/NFAT-activation is dependent on Itk. Bioinformatic analysis of NFAT-sites of the group of transcripts similarly regulated by Itk-deficiency and CsA-treatment, followed by chromatin-immunoprecipitation, revealed NFATc1-binding to the Bub1, IL7R, Ctla2a, Ctla2b, and Schlafen1 genes. Finally, to identify transcripts that are regulated by Tec-family kinases in general, we compared the expression profile of Itk-deficient T-cells with that of Btk-deficient B-cells and a common set of transcripts was found. Taken together, our study provides a general overview about the global transcriptional changes in the absence of Itk. Experiment Overall Design: CD3+ T-cells from pooled suspensions of spleen and lymph nodes of Wt and Itk knockout mice on C57BL/6 background were isolated after negative depletion. Unstimulated as well as stimulated T-cells were studied. Stimulations were done with anti-CD3 (1 mg/ml) with or without anti-CD28 (3 mg/ml) in the presence or absence of CsA (1 mg/ml) for 24 hrs. For each stimulus, at least duplicate samples were used.