Megumi Y Matsumoto

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DNA from bacteria has stimulatory effects on mammalian immune cells, which depend on the presence of unmethylated CpG dinucleotides in the bacterial DNA. In contrast, mammalian DNA has a low frequency of CpG dinucleotides, and these are mostly methylated; therefore, mammalian DNA does not have immuno-stimulatory activity. CpG DNA induces a strong(More)
MyD88, originally isolated as a myeloid differentiation primary response gene, is shown to act as an adaptor in interleukin-1 (IL-1) signaling by interacting with both the IL-1 receptor complex and IL-1 receptor-associated kinase (IRAK). Mice generated by gene targeting to lack MyD88 have defects in T cell proliferation as well as induction of acute phase(More)
The ubiquitin-proteasome pathway plays an important role in control of the abundance of cell cycle regulators. Mice lacking Skp2, an F-box protein and substrate recognition component of an Skp1-Cullin-F-box protein (SCF) ubiquitin ligase, were generated. Although Skp2(-/-) animals are viable, cells in the mutant mice contain markedly enlarged nuclei with(More)
The nucleotide sequence of the entire genome of a filamentous cyanobacterium, Anabaena sp. strain PCC 7120, was determined. The genome of Anabaena consisted of a single chromosome (6,413,771 bp) and six plasmids, designated pCC7120alpha (408,101 bp), pCC7120beta (186,614 bp), pCC7120gamma (101,965 bp), pCC7120delta (55,414 bp), pCC7120epsilon (40,340 bp),(More)
Signal transducer and activator of transcription (STAT) proteins have been shown to mediate biological actions in response to cytokines. Stat3, a member of the STAT family, is activated by a variety of cytokines, including the interleukin 6 family of cytokines, leptin, granulocyte colony-stimulating factor, and epidermal growth factor. To address the(More)
Excessive nitric oxide (NO) production in cytokine-activated beta cells has been implicated in beta cell disruption in type 1 diabetes. beta cells are very vulnerable to NO-induced apoptosis. However, the mechanism underlying this phenomenon is unclear. Low concentrations of NO that lead to apoptosis apparently do not cause severe DNA damage in mouse MIN6(More)
Monocytes/macrophages exposed to LPS show reduced responses to second stimulation with LPS, which is termed LPS tolerance. In this study, we investigated molecular mechanism of LPS tolerance in macrophages. Mouse peritoneal macrophages pre-exposed to LPS exhibited reduced production of inflammatory cytokines in a time- and dose-dependent manner. Activation(More)
Toll-like receptors (TLR) in the innate immune system have not been identified in non-mammalian vertebrates. Two types of TLR were cloned from a chicken bursa cDNA library using degenerate primers based on the consensus sequences of mouse and Drosophila Toll and designated as chicken TLR (chTLR) type 1 and type 2. Of the nine human TLRs reported to date,(More)
The constituents of mycobacteria are an effective immune adjuvant, as observed with complete Freund's adjuvant. In this study, we demonstrated that the cell wall skeleton of Mycobacterium bovis bacillus Calmette-Guérin (BCG-CWS), a purified noninfectious material consisting of peptidoglycan, arabinogalactan, and mycolic acids, induces maturation of human(More)