Project description:CD4 T cells play critical roles in promoting inflammation and helping immune responses, but knowledge of how memory CD4 T cells are regulated and how they help adaptive immune responses is limited. Using adoptive transfer of virus-specific CD4 T cells, we show that naïve CD4 T cells undergo substantial expansion following viral infection, but can induce lethal TH1-driven inflammation. In contrast, memory CD4 T cells exhibit a biased proliferation of T follicular helper (Tfh) cell subsets that correlate with improved adaptive responses and minimal tissue damage following viral infection. Importantly, our analyses revealed that type I interferon regulates the expansion of naïve CD4 T cells, but does not seem to play a critical role in regulating the expansion of memory CD4 T cells. Moreover, blockade of type I interferon signaling abrogated lethal CD4 T cell inflammation following viral infection. Taken together, these data demonstrate a previously undescribed function for memory CD4 T cells: to help adaptive immunity with minimal harm to the host. These findings are important for rational vaccine design and for improving the safety and efficacy of adoptive T cell therapies against persistent antigens. Primary and memory SMARTA cells were MACS-purified by negative selection (STEMCELL) and then FACS-sorted to 98% purity on a FACS Aria (BD Biosciences) according to congenic marker expression (CD45.1+ for secondary, and CD45.1+ CD45.2+ for primary, CD4 T cell responses).

2017-03-31 | GSE92474 | GEO

helP in P. aeruginosa bloodstream infection

Project description:helP is a prognostic biomarker in patients with Pseudomonas aeruginosa bloodstream infection

| PRJEB20829 | ENA

Genome-wide methylation in paired lung tumor/non-tumor samples using the HELP assay

Project description:In lung cancer, hypermethylation of specific gene promoters has been found during the progressive carcinogenesis. The identification of common methylation events will aid in the understanding of molecular events during neoplastic transformation and help develop biomarkers for cancer with high predictive and diagnostic value. To explore common methylation events on a genome-wide scale in lung cancer, we analyzed the methylation profiles of paired NSCLC tumor and far adjacent non-tumor samples using the HELP-microarray assay, which yields information on 1.2 million fragments throughout the genome. In this study, 24 pairs of tumor and adjacent non-tumor samples were analyzed using the HELP assay. At p = 5E-6, we identified 26,138 differentially methylated fragments (corresponding to 2 CpG sites each) in tumor versus non-tumor. The overall trend was consistent with genome-wide hypomethylation and locus specific hypermethylation (localized to CG-island containing promoters). We could identify both known and novel regions of the genome as well as specific gene-promoters that are hypermethylated in tumor versus non-tumor. The HELPassay: HpaII tiny fragment enrichment by ligation-mediated polymerase chain reaction [PCR] assay 24 pairs of NSCLC subjects, tumor and paired non-tumor samples from each subject were analyzed. Individual HpaII restriction digest profiles were compared to an internal MspI digest control, to yield differentially methylated fragments for every sample. Samples were compared intra-subject between tumor and adjacent non-tumor for these differential methylation profiles and the overall significant changes across 24 subjects were identified.

2012-03-31 | E-GEOD-35520 | biostudies-arrayexpress

CD4 help is required for the generation of a transcriptionally distinct cytolytic CD8 T cell subset that arises during chronic viral infection

Project description:CD4 help is crucial to sustain the function of exhausted CD8 T cells, yet the detailed mechanisms by which CD4 help regulates CD8 T cell differentiation and function during chronic viral infection remain elusive. Here, using single cell RNA-sequencing (scRNA-seq) we show that CD8 T cells responding to chronic viral infection are more heterogeneous than previously appreciated, with three transcriptionally distinct subsets dominating the late phase of the antiviral response. Importantly, our findings uncover the formation of a previously unrecognized CD8 T cell subset that exhibits potent cytolytic function. This subset is characterized by high expression of killer cell lectin-like receptors Klre1 and Klra9, the chemokine receptor CX3CR1, and the transcription factors T-bet and Zeb2. Notably, our data further demonstrate that the formation of this cytotoxic subset is critically dependent on CD4 help and that exploitation of this developmental pathway may be used therapeutically to enhance the killer function of CD8 T cells infiltrated into the tumor. These findings uncover novel cellular and molecular mechanisms of how CD4 help regulates CD8 T cell differentiation during persistent infection and have implications towards optimizing the generation of protective CD8 T cells in immunotherapy.

2019-12-05 | GSE129139 | GEO