Gamma-delta (γ/δ) T cells are thought to represent the first line of defense against various pathogenic microorganisms. The aim of the present study was to investigate whether γ/δ T cells were ...increased in BAL fluid (BALF) of patients with diffuse panbronchiolitis (DPB), a model of chronic lower respiratory tract infection. The study population consisted of four groups, including patients with DPB, sarcoidosis, idiopathic pulmonary fibrosis, and normal subjects. Two-color direct immunofluorescence and flow cytometry were used for analysis of peripheral blood or BALF from these patients. The percentage of peripheral blood or BALF γ/δ T cells relative to the total number of lymphocytes was similar in the four groups. Although the absolute number of γ/δ T cells in BALF was significantly higher in DPB patients compared with the other three groups, the total lymphocyte number in BALF in DPB patients was increased and the number of BALF γ/δ T cells correlated with the total lymphocyte number in BALF. Furthermore, the percentage and number of BALF γ/δ T cells were not related to a certain group of pathogenic organisms or the number of colony-forming units. Our results suggest that γ/δ T cells are unlikely to play a part in chronic lower respiratory tract infection.
Free fatty acids provide an important energy source as nutrients, and act as signalling molecules in various cellular processes. Several G-protein-coupled receptors have been identified as ...free-fatty-acid receptors important in physiology as well as in several diseases. GPR120 (also known as O3FAR1) functions as a receptor for unsaturated long-chain free fatty acids and has a critical role in various physiological homeostasis mechanisms such as adipogenesis, regulation of appetite and food preference. Here we show that GPR120-deficient mice fed a high-fat diet develop obesity, glucose intolerance and fatty liver with decreased adipocyte differentiation and lipogenesis and enhanced hepatic lipogenesis. Insulin resistance in such mice is associated with reduced insulin signalling and enhanced inflammation in adipose tissue. In human, we show that GPR120 expression in adipose tissue is significantly higher in obese individuals than in lean controls. GPR120 exon sequencing in obese subjects reveals a deleterious non-synonymous mutation (p.R270H) that inhibits GPR120 signalling activity. Furthermore, the p.R270H variant increases the risk of obesity in European populations. Overall, this study demonstrates that the lipid sensor GPR120 has a key role in sensing dietary fat and, therefore, in the control of energy balance in both humans and rodents. PUBLICATION ABSTRACT
Full text
Available for:
DOBA, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The low efficiency of transgenic animal production by microinjection has been a serious problem especially for the production of transgenic livestock. We developed a method to selectively produce ...transgenic mice using green fluorescent protein (GFP) as a marker. Using this method, we obtained eight fetuses and four live-born mice derived from 55 GFP-positive blastocysts. PCR analysis showed 11 out of 12 mice (fetuses and newborn mice) were transgenic. Southern blot analysis showed that 8 out of 12 were transgenic. GFP expression was also observed in bovine blastocysts, suggesting that this method should contribute to the efficient production of transgenic livestock.
Polyurea thin films were prepared using 4,4-diaminodiphenyl methane (MDA) and 4,4-diphenyl methane diisocyanate (MDI), by vapor deposition polymerization. Polyureas include urea bonds which contain ...NH and CO dipolar groups. The dipole orientation which was caused by corona poling was observed by Fourier Transform Infra-Red FT-IR reflectance. In diode corona poling, the dipoles are aligned best in the area directly below the needle electrode, with the degree of dipole orientation decreasing in proportion to increasing distance from this electrode. In triode corona poling, a grid electrode is set up between the needle electrode and planar electrode, and orientation is accomplished uniformly over the entire surface. Contrary to this assumption, however, we found, through FT-IR mapping analysis, that dipole orientation follows the form of a net mesh structured like a grid electrode.
Bacterial toxin ADP-ribosyltransferases, e.g. diphtheria toxin (DT) and pertussis toxin, have in common consensus sequences involved in catalytic activity, which are localized to three regions. ...Region I is notable for a histidine or arginine; region II, approximately 50-75 amino acids downstream, is rich in aromatic/hydrophobic amino acids; and region III, further downstream, has a glutamate and other acidic amino acids. A similar motif was observed in the sequence of the glycosylphosphatidylinositol-linked muscle ADP-ribosyltransferase. Site-directed mutagenesis was performed to verify the role of this motif. Proteins were expressed in rat adenocarcinoma cells, released from the cell with phosphatidylinositol-specific phospholipase C, and quantified with polyclonal antibodies. Transferase His114 in region I aligned with His21 of DT; as with DT, the H114N mutant was active. Aromatic/hydrophobic amino acids (region II) were found approximately 30-50 amino acids downstream of this histidine. Although transferase has a Glu278-Tyr-Ile sequence characteristic of region III in DT, Glu278 was not critical for activity. In an alternative region III containing Glu238-Glu239-Glu240, Glu238 and Glu240 but not Glu239 were critical. Glu240 aligned with critical glutamates in DT, Pseudomonas exotoxin, and C3 transferase. Thus, the mammalian ADP-ribosyltransferases have motifs similar to toxin ADP-ribosyltransferases, suggesting that these sequences are important in ADP-ribose transfer reactions.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
RT6.2 is a 26-kDa alloantigen expressed only on post-thymic T cells and attached to the cell membrane through a glycosylphosphatidylinositol
(GPI) anchor. It has been reported that expression of ...RT6.2 in animal models may correlate with lymphopenia and genetically-induced
insulin-dependent diabetes mellitus. Its physiological function is unclear. Since RT6.2 has significant amino acid identity
with a GPI-anchored rabbit muscle NAD:arginine ADP-ribosyltransferase, RT6.2 was expressed in rat mammary adenocarcinoma cells
and the ability of the expressed protein to catalyze ADP-ribose transfer reactions was examined. Cells transformed with the
RT6.2 gene expressed NAD glycohydrolase activity that was released from intact cells by phosphatidylinositol-specific phospholipase
C, consistent with its presence on the cell surface. A similar activity was not detected with vector-transformed cells. RT6.2
did not ADP-ribosylate simple guanidino compounds. The molecular weight of the phosphatidylinositol-specific phospholipase
C-released NAD glycohydrolase, determined by SDS-polyacrylamide gel electrophoresis, was 22,000-24,000, in good agreement
with that of native RT6.2. These results strongly suggest that the rat T cell alloantigen RT6.2 is a GPI-anchored NAD glycohydrolase.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
BACKGROUND: Sarcoidosis is a systemic granulomatous disorder of unknown origin characterised by accumulation of T lymphocytes and macrophages in multiple organs. Several cytokines and adhesion ...molecules may contribute to the accumulation of T lymphocytes in pulmonary sarcoidosis. The distribution of T lymphocyte subsets, T cell bearing CD11a and beta chemokines such as regulated on activation normal T expressed and secreted (RANTES), macrophage inflammatory peptide 1 alpha (MIP-1 alpha), and macrophage chemoattractant protein 1 (MCP-1) in bronchoalveolar lavage (BAL) fluid and peripheral blood were compared in untreated patients with sarcoidosis and normal subjects. METHODS: Flow cytometric analysis with monoclonal antibodies to cell surface antigens was used to identify T lymphocyte subsets in the BAL fluid of untreated patients with sarcoidosis (n = 40)--either without (group A, n = 12) or with (group B, n = 28) radiological evidence of pulmonary involvement--and in 22 normal subjects. The level of different beta chemokines was estimated by enzyme linked immunosorbent assay (ELISA). RESULTS: A high percentage of CD3+ cells, CD4+ cells expressing HLA-DR antigen, and a high CD4/CD8 ratio were detected in the BAL fluid of patients compared with normal subjects. In particular, CD4+ CD29+ memory T cells were significantly increased in patients with sarcoidosis. Furthermore, these cells were higher in those in group B than group A. The level of RANTES in the BAL fluid of patients was significantly higher than in normal subjects and correlated well with the percentage, number, and expression of CD29 on CD4 cells. The expression of CD11a (alpha chain of lymphocyte function associated antigen-1, LFA-1) on CD3+ cells in the BAL fluid of patients with sarcoidosis was not different from that of normal subjects. However, the expression of CD11a on CD3+ cells in the BAL fluid of patients in group A was significantly lower than that of patients in group B and normal subjects. CONCLUSIONS: These results suggest a possible interaction between activated memory T cells bearing CD11a and RANTES which may contribute to the pulmonary involvement in patients with sarcoidosis.
PDF
