Biomedical subjects

Kouichi Watanabe

Publications and source records attributed to Kouichi Watanabe.

23 records · Page 2Linked to original sources

PubMed2003

Constitutive expression of a bacterial pattern recognition receptor, CD14, in human salivary glands and secretion as a soluble form in saliva.

Saliva contains a number of proteins and glycoproteins that protect oral tissues, but little is known about the role of human saliva in innate immunity. Here we showed that human major salivary gland cells constitutively expressed a bacterial pattern recognition receptor, CD14, by immunohistochemistry. Human salivary gland cells in culture express CD14 mRNA and a 55-kDa CD14 protein in, but not on the cells, and secrete a soluble form with the same molecular mass. Human whole saliva contains a 55-kDa CD14, and the concentration of parotid saliva was 10-fold higher than whole saliva, which is comparable to that of serum CD14. Levels of CD14 in unstimulated whole and parotid saliva were unchanged before and after a meal and between unstimulated and stimulated saliva, indicating that saliva CD14 is constitutively secreted into the oral cavity. In contrast, lipopolysaccharide (LPS)-binding protein was below the detectable level. The saliva CD14 is functionally active in that it mediated the activation of CD14-lacking intestinal epithelial cells by LPS in a Toll-like receptor 4-dependent manner. These results suggested that saliva CD14 is important for the maintenance of oral health and possibly intestinal homeostasis.

Epithelial Cells↗

PubMed2003

Inflammatory responses of bovine polymorphonuclear neutrophils induced by staphylococcal enterotoxin C via stimulation of mononuclear cells.

To elucidate the pathological roles of staphylococcal enterotoxin C (SEC) in bovine staphylococcal mastitis, a histopathological analysis of SEC-inoculated mammary glands was performed. SEC-inoculated mammary glands exhibited interstitial inflammation, and the leukocytes that migrated into the gland were predominantly polymorphonuclear neutrophils (PMN). In the gland cistern tissues dissected from SEC-inoculated mammary glands, epithelial cellular degeneration was observed. We also investigated the physiological effects of SEC on PMN in vitro. PMN migration was induced by culture supernatant of SEC-stimulated peripheral blood mononuclear cells (S-PBMC sup) but not by that of nonstimulated PBMC (N-PBMC sup). The concentration of interleukin-8 was significantly (P < 0.05) higher in S-PBMC sup than N-PBMC sup, and a significantly (P < 0.05) higher mRNA expression of growth-regulated oncogenes was detected in SEC-stimulated PBMC than in nonstimulated PBMC. Milk PMN collected from SEC-inoculated mammary glands produced more than 2 times the amount of superoxide at 1 day postinoculation (dpi) than at 0 dpi in the presence of phorbol 12-myristate 13-acetate (PMA). PMN cultured with S-PBMC sup for 24 h also produced significantly (P < 0.05) larger amounts of superoxide than those cultured with N-PBMC sup in the presence of PMA. Moreover, S-PBMC sup induced the long-time survival of PMN. These results indicate that SEC induces the activation of PMN via the stimulation of mononuclear cells.

Animals↗

PubMed2003

Expression of IL-2 receptor beta and gamma chains by human gingival fibroblasts and up-regulation of adhesion to neutrophils in response to IL-2.

To investigate the role of human gingival fibroblasts (HGF), the major constituents of gingival tissue in periodontal inflammatory disease, the expression of interleukin-2 receptor (IL-2R) alpha, beta, and gamma chains was examined. Immunohistochemistry showed a pronounced accumulation of CD8(+) T cells in the inflamed lamina propria of gingival tissue from patients with adult periodontitis. HGF express IL-2Rbeta and IL-2Rgamma at mRNA and protein levels, but the expression of IL-2Ralpha could not be detected, as assessed by reverse transcriptase-polymerase chain reaction and flow cytometry. IL-2Rbeta, and -gamma expressed on HGF were functionally active, as addition of neutralizing anti-IL-2Rbeta and -gamma antibodies caused inhibition of the IL-2-induced production of monocyte chemoattractant protein-1 (MCP-1), and addition of IL-2 induced phosphorylation of Janus tyrosine kinase 3, which is critical in signaling through IL-2Rgamma in HGF. The IL-2-induced MCP-1 production was significantly inhibited by pretreatment with neutralizing antibody to IL-15. Addition of IL-2 also induced a marked up-regulation of the expression of intercellular adhesion molecule-1 (ICAM-1) on the surface of HGF, which in turn, significantly augmented the adhesion of human neutrophils, which were inhibited by an anti-ICAM-1 antibody. These results suggest that HGF express functional IL-2Rbetagamma, respond to IL-2 from infiltrated T cells, and actively participate in the inflammatory process in the periodontal region and that IL-15 produced by HGF sustains IL-2-mediated signaling in HGF.

Adult↗

PubMed2002

Expression of mRNA for glucocorticoid receptors in peripheral blood mononuclear cells of patients with Crohn's disease.

BACKGROUND: The amount of glucocorticoid (GC) receptors (GR) in immune cells might be critical for successful GC treatment of patients with Crohn's disease (CD). However, little is known about the expression of GR in CD; therefore, we carried out quantitative analyses for GR messenger (m)RNA expression in peripheral-blood mononuclear cells (PBMC) of CD. METHODS: Seventeen patients with CD and 33 healthy subjects entered into this study. We measured the GRalpha mRNA level in the PBMC of these subjects by a reverse transcription-competitive polymerase chain reaction procedure. Relative amounts for GRbeta mRNA were obtained semiquantitatively. RESULTS: The amounts of GRalpha-mRNA in the CD patients and healthy subjects were 0.053 +/- 0.052 and 0.130 +/- 0.108 (copies/copies of beta-actin mRNA), respectively. The former value was significantly lower than that of the latter (P < 0.01). The rates of the CD patients and healthy subjects expressing GRbeta-mRNA in PBMC were 41.2% and 45.5%, respectively, and there was no significant difference in the rates between the two groups (P = 0.339). However, the relative amounts of GRbeta-mRNA in the PBMC were estimated to be 1.053 x 10-5 +/- 2.540 x 10-5 for the CD patients, and 1.872 x 10-5 +/- 3.252 x 10-5 (fluorescence intensity/copies of beta-actin mRNA) for the healthy subjects, and the former was significantly smaller than the latter (P < 0.05). Moreover, there was an inverse correlation between the duration of disease (year) and the amounts of GRalpha-mRNA in the PBMC of the CD patients (P < 0.05). CONCLUSIONS: The amounts of GRalpha-mRNA and GRbeta-mRNA in the PBMC of the CD patients were lower than those of the healthy subjects. The duration of disease correlated with decreased amounts of GRalpha-mRNA in the PBMC. Furthermore, the clinical significance of the GR-mRNA status in the PBMC remains to be elucidated.

Adult↗

PubMed2002

Internal porosity of cast titanium removable partial dentures: Influence of sprue direction on porosity in circumferential clasps of a clinical framework design.

STATEMENT OF PROBLEM: Although internal porosity is a potential risk factor for clasp fracture, little is known about its frequency in the clasps of titanium removable partial dentures. PURPOSE: This study investigated the influence of the direction of auxiliary sprues on porosity in the circumferential clasps of a pressure-cast titanium removable partial denture. MATERIAL AND METHODS: Wax patterns of a removable partial denture framework were made on 10 identical refractory casts of a Kennedy class II, modification 1, mandibular partially edentulous arch. For the auxiliary sprues directed to the circumferential clasps, 2 designs were used: straight and curved. Casting was performed in a 1-chamber pressure casting machine. Pore number and size were assessed on radiographs of the castings. The data were analyzed with the 2-tailed Student t test (P <.05). Randomly selected specimens were sectioned for morphologic observation of the internal surface of the pores. RESULTS: The number of pores >or=0.5 mm diameter and the total number of pores were significantly lower in the molar lingual arms of the curved sprue group than in the corresponding clasp arms of the straight sprue group (P =.03 and P =.009, respectively). No significant differences between the 2 groups were found for pores of any size in other locations. The pores had smooth internal surfaces. CONCLUSION: Within the limitations of this study, the curved sprue design produced significantly less porosity in the circumferential clasp arms of a cast titanium removable partial denture than the conventional straight design. The results suggest that internal porosity in titanium castings can be controlled through sprue design.

Dental Casting Technique↗