Shoichi Hosoya

Immunobiotic Lactobacillus jensenii Elicits anti-inflammatory activity in porcine intestinal epithelial cells by modulating negative regulators of the toll-like receptor signaling pathway

ABSTRACT The effect of Lactobacillus jensenii TL2937 on the inflammatory immune response triggered by enterotoxigenic Escherichia coli (ETEC) and lipopolysaccharide (LPS) in a porcine intestinal epitheliocyte cell line (PIE cells) was evaluated. Challenges with ETEC or LPS elicited Toll-like receptor 4 (TLR4)-mediated inflammatory responses in cultured PIE cells, indicating that our cell line may be useful for studying inflammation in the guts of weaning piglets. In addition, we demonstrated that L. jensenii TL2937 attenuated the expression of proinflammatory cytokines and chemokines caused by ETEC or LPS challenge by downregulating TLR4-dependent nuclear factorκB (NF-κB) and mitogen-activated protein kinase (MAPK) activation. Furthermore, we demonstrated that L. jensenii TL2937 stimulation of PIE cells upregulated three negative regulators of TLRs: A20, Bcl-3, and MKP-1, deepening the understanding of an immunobiotic mechanism of action. L. jensenii TL2937-mediated induction of negative regulators of TLRs would have a substantial physiological impact on homeostasis in PIE cells, because excessive TLR inflammatory signaling would be downregulated. These results indicated that PIE cells can be used to study the mechanisms involved in the protective activity of immunobiotics against intestinal inflammatory damage and may provide useful information for the development of new immunologically functional feeds that help to prevent inflammatory intestinal disorders, including weaning-associated intestinal inflammation.

High-Tc Superconductivity in New Oxide Systems II

Superconducting transitions have been observed by resistivity measurements for several specimens of L-M-Cu-O system with L being Yb, Lu, Y, La and the mixture of Yb and La, and M being Ba and mixture of Ba and Sr. The onset transition temperature Tc becomes very close to 100 K. Since Yb-Ba-Cu-O and Lu-Ba-Cu-O have almost the same transition temperatures (Tc>90 K), the magnetic moment of Yb atoms does not seem to destroy the superconductivity in the present system. This suggests that the superconductivity occurs in certain parts of the system which are, at least, far from the Yb atom sites. Therefore M-Cu-O or Cu-O system may have an essential role in the occurrence of the superconductivity.

Raman Study of High Tc Superconductors (La1-xSrx)2CuO4

Lattice vibrations in high Tc superconductors (La1-xSrx)2CuO4 are investigated by Raman scattering using single crystals. In La2CuO4 the 664 and 153 cm-1 peaks are resonantly enhanced at low temperatures. The enhancement is caused by the electronic transition spanning the quasi-square Fermi surface to the nesting directions. The 664 cm-1 mode is assigned to the planar breathing mode which strongly interacts with electrons at the Fermi level and the 796 cm-1 mode in (La0.925Sr0.075)2CuO4 is tentatively assigned to the axial breathing mode.

Immunobiotic lactic acid bacteria beneficially regulate immune response triggered by poly(I:C) in porcine intestinal epithelial cells

This study analyzed the functional expression of TLR3 in various gastrointestinal tissues from adult swine and shows that TLR3 is expressed preferentially in intestinal epithelial cells (IEC), CD172a+CD11R1high and CD4+ cells from ileal Peyers patches. We characterized the inflammatory immune response triggered by TLR3 activation in a clonal porcine intestinal epitheliocyte cell line (PIE cells) and in PIE-immune cell co-cultures, and demonstrated that these systems are valuable tools to study in vitro the immune response triggered by TLR3 on IEC and the interaction between IEC and immune cells. In addition, we selected an immunobiotic lactic acid bacteria strain, Lactobacillus casei MEP221106, able to beneficially regulate the anti-viral immune response triggered by poly(I:C) stimulation in PIE cells. Moreover, we deepened our understanding of the possible mechanisms of immunobiotic action by demonstrating that L. casei MEP221106 modulates the interaction between IEC and immune cells during the generation of a TLR3-mediated immune response.

Ultraviolet Photoemission Study of High-Tc Superconductor (La1-xSrx)2CuO4-δ

Ultraviolet photoemission spectra of high-Tc superconductor (La1-xSrx)2CuO4-δ, (x=0.075 and δ≤0.04) are presented. The experimental result was compared with the band calculations of La2CuO4 by Mattheiss and Takegahara et al. It was found that as regards the valence-band width (about 7 eV) the experiment and the calculations are in good agreement with each other, but the position of the calculated valence bands contributed mainly by weakly bonding Cu(3d)-O(2p) states are shiftd toward the lower binding energy by about 1 eV with respect to the experiment. The possible origins for this discrepancy were discussed.

Advanced application of porcine intestinal epithelial cells for the selection of immunobiotics modulating toll-like receptor 3-mediated inflammation

PURPOSE In this study, we aimed to characterize toll-like receptor (TLR)-3-mediated inflammatory immune response in porcine intestinal epithelial (PIE) cells and in PIE-immune cell co-cultures and, to evaluate if these in vitro systems are useful for selecting immunomodulatory lactic acid bacteria. RESULTS We demonstrated that these systems are valuable tools for the in vitro study of the inflammatory response triggered by TLR3 in intestinal epithelial cells (IECs) and of the interaction between IECs and immune cells. In addition, we showed that PIE cells could be used for the selection of immunobiotic lactobacilli strains with anti-inflammatory activities. We found that Lactobacillus casei MEP221114 is an immunobiotic candidate for modulation of TLR3-mediated inflammatory responses. CONCLUSION The present study deepened our understanding of the mechanisms of immunobiotic action by demonstrating that the interaction between some lactobacilli strains and IECs can up-regulate the mRNA expression of TLR negative regulators and that this effect could help to regulate the production of inflammatory mediators during the generation of a TLR3-mediated immune response.

A newly established bovine intestinal epithelial cell line is effective for in vitro screening of potential antiviral immunobiotic microorganisms for cattle

Abstract We evaluated whether a bovine intestinal epithelial (BIE) cell line could serve as a useful in vitro model system for studying antiviral immune responses in bovine intestinal epithelial cells (IECs) and for the primary screening of immunobiotic microorganisms with antiviral protective capabilities. Immunofluorescent analyses revealed that toll-like receptor 3 (TLR3) was expressed in BIE cells, and the results of real-time quantitative PCR showed that these cells respond to stimulation with poly(I:C) by up-regulating pro-inflammatory cytokines and type I interferons. In addition, we demonstrated that BIE cells are useful for the primary screening of immunobiotic lactic acid bacteria strains which are able to beneficially modulate antiviral immune responses triggered by TLR3 activation in bovine IECs. The characterization of BIE cells performed in the present study represents an important step towards the establishment of a valuable bovine in vitro system that could be used for the development of immunomodulatory feed for bovine hosts.

Raman and Infrared Studies of Oxide Superconductors (La1-xMx)2CuO4

Raman and infrared studies of lattice vibrations in new superconductors (La1-xMx)2CuO4 are presented. The 664 cm-1 mode which shows resonant enhancement in La2CuO4 is assigned to the planar breathing mode which strongly interacts with electrons at EF. This resonant scattering is produced by the electronic transition spanning the quasi-square Fermi surface to the nesting directions. In the spectra of Im(e) a strong peak appears at 246 cm-1 on substituting Sr for La. It is suggested that this mode is related to the electronic transition.

Photoelectron Spectroscopy of High-Tc Superconductor (La1-xSrx)2CuO4-δ

Electronic structure and chemical state of high-Tc superconductor (La1-xSrx)2CuO4-δ (x=0.075 and δ0.04) were studied by photoelectron spectroscopy. Resonant photoemission with synchrotron radiation snowed that the copper atom in the La–Sr–Cu–0 system is mostly divalent. The experimental results were compared with the band calculations performed for La2CuO4.

Photoemission Study of Single Crystal Bi2Sr2CaCu2O8

Photoemission measurements with synchrotron radiation have been performed on single crystal Bi2Sr2CaCu208. Two energy bands with dispersion of 0.2–0.5 eV were observed in the vicinity of the Fermi level and one of them crosses the Fermi level midway between the center and boundary of the Brillouin zone, giving a clear evidence for existence of a Fermi surface. The Fermi-edge peak exhibits a pronounced enhancement at photon energy of the 0 2s core threshold, meaning a dominant 0 2p nature of the Fermi-edge states. These results indicate existence of the Fermi-liquid states with dominant 0 2p nature in the high-Tc superconductor. The superconductivity could be driven by formation of Cooper-pairs of the 0 2p holes in the Fermi-liquid states, probably through the spin or charge fluctuation.