Laboratory of Microbiology and Immunology

Yasuyuki imai, Ph.D. (Immunology)

Assistant Professor
Masaki Miyake, Ph.D. (Bacteriology)

Assistant Professor
Kohta Kurohane, Ph.D. (Immunology)

Research Assistant Professor
Katsuhiro Nakanishi, Ph.D. (Immunology)

Research Interest

Yasuyuki Imai
(1) Mucosal immunology focused on acquired immunity
Immunoglobulin A (IgA) is supposed to prevent entry of harmful antigens though mucosal surface. We established mouse monoclonal antibodies of IgA class against Shiga toxin, cholera toxin, and ovalubumin. We are interested in how Shiga toxin invades intestinal epithelium and whether secretory IgA can prevent entry of toxins. We also focus on the production of Shiga toxin-specific secretory IgA by a plant expression system aiming at edible IgA therapeutics as well as high profile functional food.

(2) Adjuvant effects of chemicals in allergy
Some chemicals may serve as an adjuvant during sensitization to other chemical haptens. We have been studying a mouse contact sensitivity model using fluorescein isothiocyanate as a hapten. We found some types of phthalate esters exhibited adjuvant effects during sensitization, partly due to the enhancement of dendritic cell trafficking from skin sites to the draining lymph nodes. We demonstrated that phthalate esters with adjuvant activity stimulate transient receptor potential (TRP) channels. We are interested in the relationship between skin sensitization and stimulation of sensory neurons.

Masaki Miyake
(1) Molecular pathogenesis of Legionella pneumophila
Legionella pneumophila is the causative agent of Legionnaires’ disease. An important hallmark of the pathogenesis of this bacterium is their ability to manipulate host cell processes, creating a specified replicative niche within host cells. The establishment of these specialized phagosomes is mediated by the Icm/Dot Type IV secretion system, which is essential for the intracellular growth of L. pneumophila. L. pneumophila utilizes the Icm/Dot system to inject many effector molecules into the host cell cytosol to survive and replicate in the intracellular compartment through modulation of phagosome biogenesis. There are still many unknown things about the mechanism of intracellular growth of L. pneumophila. We are interested in understanding what bacterial and host factors regulate intracellular survival and replication of L. pneumophila and how they work during the infection process.
(2) A basic study on development of inhaled drugs for tuberculosis treatment
Tuberculosis is one of the world’s most intractable infectious diseases. We are currently interested in development of inhaled drugs for tuberculosis treatment. Collaborating with another lab, we are preparing various types of anti-tuberculosis drug-containing microparticles or nanoparticles and assessing their antibacterial activity. Furthermore, we are just working on development of inhaled drugs for tuberculosis treatment which work with a novel mechanism.

Kohta Kurohane
Development of Vaccine using liposomes

Selected Publications
K. Shoji, T. Takahashi, K. Kurohane, K. Iwata, T. Matsuoka, S. Tsuruta, T. Sugino, M. Miyake, T. Suzuki, and Y. Imai: Recombinant IgA specific for influenza A virus hemagglutinin: production, functional analysis and formation of secretory IgA. Viral Immunol., in press (2015)

K. Kurohane, K. Nagano, K. Nakanishi, K. Iwata, M. Miyake, and Y. Imai: Shiga toxin-induced apoptosis is more efficiently inhibited by dimeric recombinant hybrid-IgG/IgA immunoglobulins than by the parental IgG monoclonal antibodies. Virulence, 5, 819–824 (2014)

K. Iwata, K. Kurohane, K. Nakanishi, M. Miyake, and Y. Imai: Stable expression and characterization of monomeric and dimeric recombinant hybrid-IgG/IgA immunoglobulins specific for Shiga toxin. Biol. Pharm. Bull., 37, 1510–1515 (2014) Highlighted Paper (Editor-in-Chief selection)

K. Nakanishi, S. Narimatsu, S. Ichikawa, Y. Tobisawa, K. Kurohane, Y. Niwa, H. Kobayashi and Y. Imai: Production of hybrid-IgG/IgA plantibodies with neutralizing activity against Shiga toxin 1. PLoS ONE, 8, e80712 (2013)

K. Tsuboi, J. Hirakawa, E. Seki, Y. Imai, Y. Yamaguchi, M. Fukuda and H. Kawashima: Role of high endothelial venule-expressed heparan sulfate in chemokine presentation and lymphocyte homing. J. Immunol., 191, 448–455 (2013)

K. Kurohane, Y. Sahara, A. Kimura, M. Narukawa, T. Watanabe, T. Daimon, and Y. Imai: Lack of transient receptor potential melastatin 8 activation by phthalate esters that enhance contact hypersensitivity in mice. Toxicol. Lett., 217, 192–196 (2013)

T. Shiba, T. Tamai, Y. Sahara, K. Kurohane, T. Watanabe, and Y. Imai: Transient receptor potential ankyrin 1 activation enhances hapten sensitization in a T-helper type 2-driven fluorescein isothiocyanate-induced contact hypersensitivity mouse model. Toxicol. Appl. Pharmacol., 264, 370–376 (2012)

T. Harada, T. Tanikawa, Y. Iwasaki, M. Yamada, Y.Imai, and M. Miyake: Phagocytic entry of Legionella pneumophila into macrophages through phosphatidylinositol 3, 4, 5-trisphosphate-independent pathway. Biol. Pharm. Bull., 35, 1460-1468 (2012)

C. Kobayashi, K. Kurohane, and Y. Imai: High dose dietary pyridoxine induces T-helper type 1 polarization and decreases contact hypersensitivity response to fluorescein isothiocyanate in mice. Biol. Pharm. Bull., 35, 532–538 (2012)

Y. Tobisawa, T. Maruyama, T. Tanikawa, K. Nakanishi, K. Kurohane, and Y. Imai: Establishment of recombinant hybrid-IgG/IgA immunoglobulin specific for Shiga toxin. Scand. J. Immunol., 76, 574–584 (2011)

T. Tanikawa, K. Kurohane, and Y. Imai: Regulatory effect of cannabinoid receptor agonist on chemokine-induced lymphocyte chemotaxis. Biol. Pharm. Bull., 34, 1090–1093 (2011)

Y. Ohmichi, J. Hirakawa, Y. Imai, M. Fukuda, and H. Kawashima: Essential role of peripheral node addressin in lymphocyte homing to nasal-associated lymphoid tissues and allergic immune responses. J. Exp. Med., 208, 1015–1025 (2011)

J. Hirakawa, K. Tsuboi, K. Sato, M. Kobayashi, S. Watanabe, A. Takakura, Y. Imai, Y. Ito, M. Fukuda, and H. Kawashima: Novel anti-carbohydrate antibodies reveal the cooperative function of sulfated N- and O-glycan in lymphocyte homing. J. Biol. Chem., 285, 40864–40878 (2010)

T. Hayashi, M. Nakamichi, H. Naitou, N. Ohashi, Y. Imai, and M. Miyake: Proteomic analysis of growth phase-dependent expression of Legionella pneumophila proteins which involves regulation of bacterial virulence traits. PLoS One, 5, e11718 (2010)

T. Matsuda, T. Maruyama, H. Iizuka, A. Kondo, T. Tamai, K. Kurohane, Y. Imai: Phthalate esters reveal skin-sensitizing activity of phenethyl isothiocyanate in mice. Food Chem. Toxicol., 48, 1704–1708 (2010)

Y. Tobisawa, Y. Imai, M. Fukuda, and H. Kawashima: Sulfation of colonic mucins by N-acetylglucosamine-6-O-sulfotransferase-2 and its protective function in experimental colitis in mice. J. Biol. Chem., 285, 6750–6760 (2010)

T. Tanikawa, K. Kurohane, and Y. Imai: Regulatory effect of lysophosphatidic acid on lymphocyte migration. Biol. Pharm. Bull., 33, 204–208 (2010)

T. Matsuda, K. Kurohane, and Y. Imai: Di-(2-ethylhexyl) phthalate enhances skin sensitization to isocyanate haptens in mice. Toxicol. Lett., 192, 97–100 (2010)

M. Kashiwamura, K. Kurohane, T. Tanikawa, A. Deguchi, D. Miyamoto, and Y. Imai: Shiga toxin kills epithelial cells isolated from distal but not proximal part of mouse colon. Biol. Pharm. Bull., 32, 1614–1617 (2009)

T. Shiba, T. Maruyama, K. Kurohane, Y. Iwasaki, T. Watanabe, and Y. Imai: TRPA1 and TRPV1 activation is a novel adjuvant effect mechanism in contact hypersensitivity. J. Neuroimmunol., 207, 66–74 (2009)

T. Taniguchi, T. Harada, T. Hayashi, T. Tanikawa, K. Kurohane, M. Miyake, and Y. Imai: Elevated production of Legionella-specific immunoglobulin A in A/J mice is accompanied by T-helper 1-type polarization. Immunol. Lett., 121, 123–126 (2008)

T. Tanikawa, T. Ishikawa, T. Maekawa, K. Kurohane, and Y. Imai: Characterization of monoclonal immunoglobulin A and G against Shiga toxin binding subunits produced by intranasal immunization. Scand. J. Immunol., 68, 414–422 (2008)

T. Hayashi, M. Miyake, T. Fukui, N. Sugaya, T. Daimon, S. Itoh, T. Oku, T.Tsuji, S. Toyoshima, and Y. Imai: Exclusion of actin-binding protein p57/coronin-1 from bacteria-containing phagosomes in macrophages infected with Legionella.
Biol. Pharm. Bull., 31, 861–865 (2008)

T. Harada, M. Miyake, and Y. Imai: Evaluation of Legionella pneumophila from the bactericidal system by reactive oxygen species (ROS) in macrophages. Microbiol. Immunol., 51, 1161–1170 (2007)

T. Tanikawa, K. Kurohane and Y. Imai: Production and characterization of IgA monoclonal antibody against ovalbumin. Hybridoma, 26, 328–332 (2007)

T. Tanikawa, K. Kurohane, and Y. Imai: Induction of preferential chemotaxis of unstimulated B-lymphocytes by 2-arachidonoylglycerol in immunized mice. Microbiol. Immunol., 51, 1013–1019 (2007)

T. Maruyama, T. Shiba, H. Iizuka, T. Matsuda, K. Kurohane, and Y. Imai: Effects of phthalate esters on dendritic cell subsets and interleukin-4 production in fluorescein isothiocyanate-induced contact hypersensitivity. Microbiol. Immunol., 51, 321–326 (2007)

T. Maruyama, H. Iizuka, Y. Tobisawa, T. Shiba, T. Matsuda, K. Kurohane, and Y. Imai: Influence of local treatments with capsaicin or allyl isotiocyanate in the sensitization phase of an FITC-induced contact sensitivity model. Int. Arch. Allergy Immunol., 143, 144–154 (2007)

Y. Imai, A. Kondo, H. Iizuka, T. Maruyama, and K. Kurohane: Effects of phthalate esters on the sensitization phase of contact hypersensitivity induced by fluorescein isothiocyanate. Clin. Exp. Allergy, 36, 1462–1468 (2006)

M. Miyake, T. Fukui, and Y. Imai: Differences in protein synthesis between wild type and intracellular growth-deficient strains of Legionella pneumophila in U937 and Acanthamoeba polyphaga. Microb. Pathog., 40, 161–170 (2006)

M. Miyake, T. Watanabe, H. Koike, M. Molmeret, Y. Imai, and Yousef Abu Kwaik: Characterization of Legionella pneumophila pmiA, an essential gene for infectivity of protozoa and macrophages. Infect. Immun., 73, 6272–6282 (2005)

Y. Imai, T. Ishikawa, T. Tanikawa, H. Nakagami, T. Maekawa, K. Kurohane: Production of IgA monoclonal antibody against Shiga toxin binding subunits employing nasal-associated lymphoid tissue. J. Immunol. Methods, 302, 125–135 (2005)

K. Sato, Y. Imai, N. Higashi, Y. Kumamoto, T. M. Onami, S. M. Hedrick, and T. Irimura: Lack of antigen-specific tissue remodeling in mice deficient in the macrophage galactose-type calcium-type lectin 1/CD301a. Blood, 106, 207–215 (2005)

Y. Imai, R. Nagai, Y. Ono, T. Ishikawa, H. Nakagami, T. Tanikawa, and K. Kurohane: Production of secretory immunoglobulin A against Shiga toxin binding subunits in mice by mucosal immunization. Infect. Immun., 72, 889–895 (2004)

Y. Imai, T. Fukui, K. Kurohane, D. Miyamoto, Y. Suzuki, T. Ishikawa, Y. Ono, and M. Miyake: Restricted expression of Shiga toxin binding sites on mucosal epithelium of mouse distal colon. Infect. Immun., 71, 985–990 (2003)

Y. Imai, T. Fukui, A. Ikegaya, T. Ishikawa, Y. Ono, and K. Kurohane: Lack of Shiga-like toxin binding sites in germinal centers of mouse lymphoid tissues. Immunology, 105, 509–514 (2002)

Y. Imai, Y. Matsuura, Y. Ono, T. Ishikawa, and Y. Ito: Demonstration of the pH sensitive binding of multivalent carbohydrate ligands to immobilized Shiga-like toxin 1 B subunits. J. Biochem. (Tokyo), 130, 665–670 (2001)

S. Miyashita, Y. Matsuura, D. Miyamoto, Y. Suzuki, and Y. Imai: Development of recombinant B subunit of Shiga-like Toxin 1 as a probe to detect carbohydrate ligands in immunochemical and flowcytometric application. Glycoconj. J., 16, 697–705 (1999)

K. Sato, Y. Imai and T. Irimura: Contribution of dermal macrophage trafficking in the sensitization phase of contact hypersensitivity. J. Immunol., 161, 6835–6844 (1998)