Project description:Gene expression of Tfap4â/â and WT CD8+ T cells were compared after activation with anti-CD3 and anti-CD28 antibodies in vitro or with Listeria monocytogenes infection in vivo For in vitro activation, naive CD8+ T cells were purified from WT and Tfap4â/â mice and activated with anti-CD3 and anti-CD28 antibodies for 72 hours. For in vivo activation, naive CD8+ T cells from Tfap4â/â OT-I or control WT OT-I TCR transgenice mice were adoptively transferred to congenic host mice that were subsequently infected with Listeria mnocytogenes expression ovalbumin. Activated OT-I cells were harvested 48 hours after infection.
Project description:To determine functional overlap between cMyc and AP4 in CD8+ T cell priming, we retrovirally expressed cMyc or AP4 in cMyc-deficient CD8+ T cells and examined gene expression after activation. Naive CD8+ T cells from Myc conditional knockout mice with a tamoxifen inducible Cre transgene were retrovirally transduced with Myc or AP4 followed by a treatment with 4-hydroxytamoxifen in the presence of IL-7 for 2 days. RNA was harvested 48 hours after restimulation of transduced cells with anti-CD3 antibody and gene expression was compared by microarray. CD8+ T cells from littermate wildtype mice that were transduced with an empty retrovirus were used as control.
Project description:Interleukin 2 (IL-2) promotes proliferation and differentiation of CD8+ T cells in vitro and in vivo. To define gene expression regulated by IL-2, we purified naive CD8+ T cells, activated them for 2 days followed by treatment with recombinant IL-2 or with neutralizing antibody against IL-2 and compared gene expression between the two treatments. Total RNA was extracted using the NucleoSpin RNA XS kit (Macherey-Nagel), amplified using a PicoSL RNA amplification kit (Nugen) and biotinylated with Encore biotin module (Nugen). Labeled RNA was hybridized to Mouse Gene 1.0ST microarrays (Affymetrix) according to the manufacturer’s instruction.
Project description:Glucose is essential for T cell proliferation and function, yet the metabolic fates of glucose critical for T cell responses in vivo remain poorly defined. Here, we identify glycosphingolipid (GSL) biosynthesis as an essential arm of glucose metabolism that fuels CD8+ T cell expansion and cytotoxic function in vivo. Using stable isotope tracing, we show that CD8+ effector T (Teff) cells in vivo use glucose to synthesize uridine diphosphate-glucose (UDP-Glc), a common precursor for glycogen, glycan, and GSL biosynthesis. Blocking GSL production–by targeting the enzymes UDP-Glc pyrophosphorylase 2 (UGP2) or UDP-Glc ceramide glucosyltransferase (UGCG)–blunts CD8+ T cell expansion and cytotoxic activity without impacting glucose-dependent energy production. Mechanistically, we show that glucose-dependent GSL biosynthesis (via UGCG) maintains lipid integrity at the plasma membrane and is required for lipid raft aggregation following T cell receptor (TCR) stimulation. CD8+ T cells lacking UGCG display poor cytotoxic function and reduced tumor control in vivo. Together, our data highlight GSL biosynthesis as an essential metabolic fate for glucose–independent of energy production–required to maintain membrane lipid homeostasis and CD8+ T cell cytotoxic function in vivo.
Project description:Little is known about the global transcriptional program underlying T-cell activation and T-cell response to oxidative stress. Using DNA microarrays and Q-RT-PCR, we examined the transcriptional profile of human T-cell activation and T-cell response to H2O2 stress. The goal of this study was to identify genes involved in the various facets of human T-cell activation and T-cell response to H2O2 stress. Experiment Overall Design: T cells isolated from peripheral blood were cultured with CD3, CD28, and IL-2 to induce T-cell activaiton. Samples were splited into two parts before the cutlure started, one treated with 25 uM H2O2 for 10 minutes, the other intact. At each timepoint, cells were harvested and frozen for RNA isolation. Three biological replicate experiments were analyzed and approximately one-half of the samples from each experiment were technically replicated. Hybridizations were performed in a reference design with all samples labeled with Cy3 and a reference thymus total RNA labeled with Cy5.
Project description:Little is known about the global transcriptional program underlying CD8+ T-cell activation. Using DNA microarrays and Q-RT-PCR, we examined the transcriptional profile of human CD8+ T-cell activation. The goal of this study was to identify genes involved in the various facets of human CD8+ T-cell activation. Experiment Overall Design: CD8+ T cells isolated from peripheral blood were cultured with CD3, CD28, with or without IL-2 to induce T-cell activation. At each timepoint, cells were harvested and frozen for RNA isolation. Three biological replicate experiments were analyzed and approximately one-half of the samples from each experiment were technically replicated. Hybridizations were performed in a reference design with all samples labeled with Cy3 and a reference thymus total RNA labeled with Cy5.
Project description:Little is known about the global transcriptional program underlying CD4+ T-cell activation. Using DNA microarrays and Q-RT-PCR, we examined the transcriptional profile of human CD4+ T-cell activation. The goal of this study was to identify genes involved in the various facets of human CD4+ T-cell activation. Experiment Overall Design: CD4+ T cells isolated from peripheral blood were cultured with CD3, CD28, with or without IL-2 to induce T-cell activation. At each timepoint, cells were harvested and frozen for RNA isolation. Three biological replicate experiments were analyzed and approximately one-half of the samples from each experiment were technically replicated. Hybridizations were performed in a reference design with all samples labeled with Cy3 and a reference thymus total RNA labeled with Cy5.
Project description:We introduce a microfluidic platform that enables off-chip single-cell RNA-seq after multigenerationa lineage tracking under controlled culture conditions. Examination of lineage and cell cycle dependent transcriptional profiles in two cell types
Project description:Transcription factors that regulate quiescence, proliferation, and homing of lymphocytes are critical for effective immune system function. In the present study, we demonstrated that the transcription factor ELF4 directly activates the tumor suppressor KLF4 downstream of T cell receptor (TCR) signaling to induce cell cycle arrest in naïve CD8+ T cells. Elf4- and Klf4-deficient mice accumulated CD8+CD44hi T cells during steady-state conditions and generated more memory T cells after immunization. The homeostatic expansion of CD8+CD44hi T cells in Elf4-null mice resulted in a redistribution of cells to non-lymphoid tissue due to reduced expression of the transcription factor KLF2, and the surface proteins CCR7 and CD62L. This work describes the combinatorial role of lymphocyte-intrinsic factors in the control of T cell homeostasis, activation and homing. Experiment Overall Design: CD8 T cells were purified from spleen of wild type and Elf4-/- mice and CD8 T cells were left untreated or activated in vitro by culturing on anti-CD3 coated plates and anti-CD28 in media (RPMI 10% FBS supplemented with 5% T-stim) for 3.5 days. Experiment Overall Design: RNAs isolated from wild type and Elf4 -/- CD8+ T cells were used in Affimetrix oligonucleotide arrays either untreated or after 3.5 days of activation.