A protective role of gamma/delta T cells in primary infection with Listeria monocytogenes in mice.

We have previously reported that T cells bearing T cell receptors (TCRs) of gamma/delta type appear at a relatively early stage of primary infection with Listeria monocytogenes in mice. To characterize the early-appearing gamma/delta T cells during listeriosis, we analyzed the specificity and cytokine production of the gamma/delta T cells in the peritoneal cavity in mice inoculated intraperitoneally with a sublethal dose of L. monocytogenes. The early-appearing gamma/delta T cells, most of which were of CD4-CD8- phenotype, proliferated and secreted IFN-gamma and macrophage chemotactic factor in response to purified protein derivative from Mycobacterium tuberculosis, or recombinant 65-kD heat-shock protein derived from M. bovis but not to heat-killed Listeria. To further elucidate the potential role of the gamma/delta T cells in the host-defense mechanism against primary infection with Listeria, we examined the effects of in vivo administration of monoclonal antibodies (mAbs) against TCR-gamma/delta or TCR-alpha/beta on the bacterial eradication in mice infected with Listeria. Most of alpha/beta T cells or gamma/delta T cells were depleted in the peripheral lymphoid organs at least for 12 d after an intraperitoneal injection of 200 micrograms TCR-alpha/beta mAb or 200 micrograms TCR-gamma/delta mAb, respectively. An exaggerated bacterial multiplication was evident at the early stage of listerial infection in the gamma/delta T cells-depleted mice, whereas the alpha/beta T cell-depleted mice exhibited much the same resistance level as the control mice at this stage although the resistance was severely impaired at the late stage after listerial infection.(ABSTRACT TRUNCATED AT 250 WORDS

Nickel catalyzed one pot synthesis of biaryls under air at room temperature

A practical, room temperature catalytic system has been developed for the synthesis of biaryls in one step from the homocoupling of in situ generated Grignard reagents using the nickel(II) complex. Molecular oxygen used as an oxidant makes the system environment friendly. The reaction system is compatible with diverse functionality to afford biaryls in appreciable yields

Measurement of the electron transmission rate of the gating foil for the TPC of the ILC experiment

We have developed a gating foil for the time projection chamber envisaged as a central tracker for the international linear collider experiment. It has a structure similar to the Gas Electron Multiplier (GEM) with a higher optical aperture ratio and functions as an ion gate without gas amplification. The transmission rate for electrons was measured in a counting mode for a wide range of the voltages applied across the foil using an $^{55}$Fe source and a laser in the absence of a magnetic field. The blocking power of the foil against positive ions was estimated from the electron transmissions.Comment: 25 pages containing 14 figures and 1 tabl

Interferon regulatory factor 8-deficiency determines massive neutrophil recruitment but T cell defect in fast growing granulomas during tuberculosis

Following Mycobacterium tuberculosis (Mtb) infection, immune cell recruitment in lungs is pivotal in establishing protective immunity through granuloma formation and neogenesis of lymphoid structures (LS). Interferon regulatory factor-8 (IRF-8) plays an important role in host defense against Mtb, although the mechanisms driving anti-mycobacterial immunity remain unclear. In this study, IRF-8 deficient mice (IRF-8−/−) were aerogenously infected with a low-dose Mtb Erdman virulent strain and the course of infection was compared with that induced in wild-type (WT-B6) counterparts. Tuberculosis (TB) progression was examined in both groups using pathological, microbiological and immunological parameters. Following Mtb exposure, the bacterial load in lungs and spleens progressed comparably in the two groups for two weeks, after which IRF-8−/− mice developed a fatal acute TB whereas in WT-B6 the disease reached a chronic stage. In lungs of IRF-8−/−, uncontrolled growth of pulmonary granulomas and impaired development of LS were observed, associated with unbalanced homeostatic chemokines, progressive loss of infiltrating T lymphocytes and massive prevalence of neutrophils at late infection stages. Our data define IRF-8 as an essential factor for the maintenance of proper immune cell recruitment in granulomas and LS required to restrain Mtb infection. Moreover, IRF-8−/− mice, relying on a common human and mouse genetic mutation linked to susceptibility/severity of mycobacterial diseases, represent a valuable model of acute TB for comparative studies with chronically-infected congenic WT-B6 for dissecting protective and pathological immune reactions

Regulatory Role of Heat Shock Protein-specific T Cells in Host Defense

1992-03During infection with L.monocytogenes, a facultative intracellular bacteria, TcR γ/δ T cells specific for 65 kd hsp precede TcR α/β T cells specific for the listerial antigens in appearance. The γ/δ T cells provide a first line of defense against the infection by recognizing exogenous and endogenous 65 kd hsp on infected cells and producing cytokines such as γIFN. The hsp-specific T cells respond quickly to antigenically diverse pathogens before antigen-specific T cells expand clonally, and they play a role in covering the gap between the phagocytic system and highly evolved immune response. 65 kd hsp-specific T cells play important roles not only in host defense mechanism against infection with various pathogens but also in induction of autoimmune disease. Both 65 kd hsp-specific γδ T cells and 65 kd hsp-specific αβ T cells abrogate the unresponsiveness of the self-reactive αβ T cells and/or B cells by producing IL-2 and contribute to induction of autoimmune disease.departmental bulletin pape

Towards the development of an EIT-based stretchable sensor for multi-touch industrial human-computer interaction systems

In human-computer interaction studies, an interaction is often considered as a kind of information or discrete internal states of an individual that can be transmitted in a loss-free manner from people to computing interfaces (or robotic interfaces) and vice-versa. This project aims to investigate processes capable of communicating and cooperating by adjusting their schedules to match the evolving execution circumstances, in a way that maximise the quality of their joint activities. By enabling human-computer interactions, the process will emerge as a framework based on the concept of expectancy, demand, and need of the human and computer together, for understanding the interplay between people and computers. The idea of this work is to utilise touch feedback from humans as a channel for communication thanks to an artificial sensitive skin made of a thin, flexible, and stretchable material acting as transducer. As a proof of concept, we demonstrate that the first prototype of our artificial sensitive skin can detect surface contacts and show their locations with an image reconstructing the internal electrical conductivity of the sensor

Manganese(I)-Catalyzed C−H Activation : The Key Role of a 7-Membered Manganacycle in H-Transfer and Reductive Elimination

Manganese-catalyzed C−H bond activation chemistry is emerging as a powerful and complementary method for molecular functionalization. A highly reactive seven-membered MnIintermediate is detected and characterized that is effective for H-transfer or reductive elimination to deliver alkenylated or pyridinium products, respectively. The two pathways are determined at MnIby judicious choice of an electron-deficient 2-pyrone substrate containing a 2-pyridyl directing group, which undergoes regioselective C−H bond activation, serving as a valuable system for probing the mechanistic features of Mn C−H bond activation chemistry

新出「福の神付き赤犬棒かるた」の影印と紹介

「いろはかるた」研究の一環として、今回は「福の神」札が付いている比較的古い「江戸いろはかるた」を紹介する。「福の神」付きかるたとしては、これまで滴翠美術館所蔵のかるたしか報告されていなかった。同版ではないものの、今回紹介するかるたによって、滴翠美術館所蔵の欠札を補うことができるので、ようやく揃いとして研究材料が提供されたことになる。研究資