The serine-threonine kinase ataxia-telangiectasia mutated (ATM) plays a central role in maintaining genomic integrity. In mice, ATM deficiency is exclusively associated with T-cell lymphoma development, whereas B-cell tumors predominate in human ataxia-telangiectasia patients. We demonstrate in this study that when T cells are removed as targets for lymphomagenesis and as mediators of immune surveillance, ATM-deficient mice exclusively develop early-onset immunoglobulin M(+) B-cell lymphomas that do not transplant to immunocompetent mice and that histologically and genetically resemble the activated B cell-like (ABC) subset of human diffuse large B-cell lymphoma (DLBCL).
View Article and Find Full Text PDFAntigen specificity is critical in immune response and requires integration of antigen-specific signals with antigen-nonspecific signals such as those provided by cytokines. The mechanism integrating these pathways is incompletely understood. We report here that antigen-specific proliferative responses of CD4(+) T cells required downmodulation of tumor suppressor p53.
View Article and Find Full Text PDFGeneration and resolution of DNA double-strand breaks is required to assemble antigen-specific receptors from the genes encoding V, D, and J gene segments during recombination. The present report investigates the requirement for ataxia telangiectasia-mutated (ATM) kinase, a component of DNA double-strand break repair, during TCRβ recombination and in subsequent TCRβ-dependent repertoire generation and thymocyte development. CD4(-)CD8(-) double negative stage 2/3 thymocytes from ATM-deficient mice have both an increased frequency of cells with DNA break foci at TCRβ loci and reduced Vβ-DJβ rearrangement.
View Article and Find Full Text PDFRecent Pat Nanotechnol
June 2012
Graphene has been the subject of many scientific investigations since exfoliation methods facilitated isolation of the two-dimensional material. During this time, new synthesis methods have been developed which have opened technological opportunities previously hindered by synthetic constraints. An update on the recent advances in graphene-based technologies, including synthesis and applications into electrical, mechanical and thermal uses will be covered.
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