Activation of invariant natural killer T cells in regional lymph nodes as new antigen-specific immunotherapy via induction of interleukin-21 and interferon-γ

Invariant natural killer T (iNKT) cells play important immunoregulatory functions in allergen-induced airway hyperresponsiveness and inflammation. To clarify the role of iNKT cells in allergic rhinitis (AR), we generated bone marrow-derived dendritic cells (BMDCs), which were pulsed by ovalbumin (OVA) and α-galactosylceramide (OVA/α-GalCer-BMDCs) and administered into the oral submucosa of OVA-sensitized mice before nasal challenge. Nasal symptoms, level of OVA-specific immunoglobulin (IgE), and T helper type 2 (Th2) cytokine production in cervical lymph nodes (CLNs) were significantly ameliorated in wild-type (WT) mice treated with OVA/α-GalCer-BMDCs, but not in WT mice treated with OVA-BMDCs. These anti-allergic effects were not observed in Jα18(-/-) recipients that lack iNKT cells, even after similar treatment with OVA/α-GalCer-BMDCs in an adoptive transfer study with CD4(+) T cells and B cells from OVA-sensitized WT mice. In WT recipients of OVA/α-GalCer-BMDCs, the number of interleukin (IL)-21-producing iNKT cells increased significantly and the Th1/Th2 balance shifted towards the Th1 dominant state. Treatment with anti-IL-21 and anti-interferon (IFN)-γ antibodies abrogated these anti-allergic effects in mice treated with α-GalCer/OVA-BMDCs. These results suggest that activation of iNKT cells in regional lymph nodes induces anti-allergic effects through production of IL-21 or IFN-γ, and that these effects are enhanced by simultaneous stimulation with antigen. Thus, iNKT cells might be a useful target in development of new treatment strategies for AR.

Templated quasicrystalline ordering of single elements and molecules

We have used quasicrystals as templates for the exploration of new epitaxial phenomena. Several interesting results have been observed in the growth on surfaces of the common Al-based quasicrystals [1]. These include pseudomorphic monolayers, quasiperiodically modulated multilayer structures, and fivefold-twinned islands with magic heights influenced by quantum size effects [1]. Here we present our recent works on the growth of various elements and molecules on a new substrate, icosahedral (i) Ag-In-Yb quasicrystal, which have resulted in various epitaxial phenomena not observed previously. The growth of Pb on the five-fold surface of i-Ag-In-Yb yields a film which possesses quasicrystalline ordering in three-dimension [2]. Using scanning tunneling microscopy (STM) and DFT calculations of adsorption energies, we find that lead atoms occupy the positions of atoms in the rhombic triacontahedral (RTH) cluster, the building block of the substrate, and thus grow in layers with different heights and adsorption energies. The adlayer–adlayer interaction is crucial for stabilizing the epitaxial quasicrystalline structure. We will also present the first example of quasicrystalline molecular layers. Pentacene adsorbs at tenfold-symmetric sites of Yb atoms around surface-bisected RTH clusters, yielding quasicrystalline order [3]. Similarly, C-60 growth on the five-fold surface of i-Al-Cu-Fe at elevated temperature produces quasicrystalline layer, where the growth is mediated by Fe atoms on the substrate surface [3]. The finding of quasicrystalline thin films of single elements and molecules opens an avenue for further investigation of the impact of the aperiodic atomic order over periodic order on the physical and chemical properties of materials.

Hydrodynamic fingering instability induced by a precipitation reaction

We experimentally demonstrate that a precipitation reaction at the miscible interface between two reactive solutions can trigger a hydrodynamic instability due to the buildup of a locally adverse mobility gradient related to a decrease in permeability. The precipitate results from an A+B→C type of reaction when a solution containing one of the reactants is injected into a solution of the other reactant in a porous medium or a Hele-Shaw cell. Fingerlike precipitation patterns are observed upon displacement, the properties of which depend on whether A displaces B or vice versa. A mathematical modeling of the underlying mobility profile confirms that the instability originates from a local decrease in mobility driven by the localized precipitation. Nonlinear simulations of the related reaction-diffusion-convection model reproduce the properties of the instability observed experimentally. In particular, the simulations suggest that differences in diffusivity between A and B may contribute to the asymmetric characteristics of the fingering precipitation patterns.

Serum glycopeptidolipid core IgA antibody levels in patients with chest computed tomography features of mycobacterium aviumintracellulare complex pulmonary disease

Measurement of serum glycopeptidolipid core IgA antibody (GPL antibody) was recently reported to show a high sensitivity and specificity for diagnosing Mycobacterium avium-intracellulare complex (MAC) pulmonary disease (MAC-PD), but its clinical value has not been confirmed. This study aims to evaluate the seropositive rate in patients with suspected MAC-PD based on chest computed tomography (CT), and to examine whether GPL antibody reflects the extent of lung involvement on CT or the number of bacteria in sputum, retrospectively. Among 66 patients with suspected MAC-PD on CT, 36 patients were negative for MAC by culture and 30 were positive. Sputum grades of MAC were evaluated by fluorochrome microscopy of sputum smears. The lungs were divided into six regions to assess the extent of disease. Serum levels of GPL antibody were measured with an enzyme immunoassay (cut-off value >0.7 U/ml). The GPL antibody positive rate was 19.4% among patients who were negative for MAC by culture versus 73.3% among culture–positive patients. The serum level of GPL antibody was significantly correlated with the sputum smear grade (r=0.43, p less than 0.05) and was also correlated with the number of lung regions showing MAC-PD features on CT (r=0.43, less than 0.05). Some MAC-PD patients may have CT features of MAC with positive level of GPL antibody, although the diagnosis cannot be confirmed by culture. GPL antibody levels reflect the pulmonary burden of MAC, as assessed from the sputum smear grade and number of involved regions on chest CT.

Gastrointestinal symptoms in idiopathic pulmonary fibrosis patients treated with pirfenidone and herbal medicine

Pirfenidone is an antifibrotic agent for patients with pulmonary fibrosis, but this drug has adverse gastrointestinal (GI) effects. The first aim of this study was to assess GI symptoms due to pirfenidone by using a new questionnaire for reflux symptoms and dismotility symptoms. Whether adding herbal medicine of rikkunshi-to improved GI symptoms due to pirfenidone therapy was also investigated. This was a randomized controlled trial performed on 17 IPF patients. The patients were assigned to two groups, and the study period was 8 weeks. The pirfenidone group received pirfenidone therapy for 8 weeks with add-on rikkunshi-to from 4 weeks, while the control group did not receive either of these agents. To assess the effects of RK, plasma levels of acyl-ghrelin and des-acyl-ghrelin, serum KL-6 and surfactant protein-D, and pulmonary function tests were monitored. GI symptoms were most severe during the initial 2 weeks of pirfenidone therapy at a dose of 600 mg/day. Both reflux symptoms and dismotility symptoms deteriorated. Rikkunshi-to improved GI symptoms to the level prior to pirfenidone therapy. Plasma levels of des-acyl-ghrelin and acyl-/des-acyl-ghrelin ratio changed significantly at 8 weeks compared to 2 weeks. GI adverse events due to PFD were most severe in the first 2 weeks of treatment at a dose of 600 mg/day, and both reflux and dismotility symptoms deteriorated, but the drug was well tolerated at 1200 mg/day. Rikkunshi-to contributed to improvement of GI symptoms, but plasma ghrelin levels did not reflect the improvement of GI symptoms.

Adjunct antibiotic combination therapy for steroid-refractory or -dependent ulcerative colitis: an open-label multicentre study

BACKGROUND

We previously demonstrated that antibiotic combination therapy is effective for induction and maintenance of ulcerative colitis (UC) remission.

AIM

To assess whether antibiotic combination therapy is effective for active UC refractory to or dependent on steroids in a multicentre, open-label trial.

METHODS

We enrolled 30 patients with steroid-refractory and 64 with steroid-dependent active UC. These patients received three-times-daily by mouth amoxicillin 500 mg, tetracycline 500 mg and metronidazole 250 mg, for two weeks, as well as conventional treatment. Symptom assessment and colonoscopic evaluation were performed before enrolment and at 3 and 12 months after treatment completion. Clinical response was defined as a Lichtiger symptom score decrease in ≥3 points and clinical remission as a score ≤4.

RESULTS

Nineteen of the 30 steroid-refractory (63.3%) and 47 of the 64 steroid-dependent (73.4%) patients showed a clinical response within 2 weeks. At 3 and 12 months, 60% and 66.6% of steroid-refractory patients, and 56.3% and 51.6% of steroid-dependent patients, respectively, achieved clinical remission. In the steroid-dependent group, 39 of the 64 patients (60.9%) were able to stop steroid therapy and remained in remission for 3 months. Three (10%) steroid-refractory and four (6.3%) steroid-dependent patients underwent colectomy.

CONCLUSIONS

This multicentre, long-term follow-up study suggests 2 week antibiotic combination therapy to be effective and safe in patients with active UC refractory to or dependent on steroids.

Tracheobronchial stenosis evaluated by inspiratory and expiratory three-dimensional computed tomography and impulse oscillation with three-dimensional color imaging in a patient with relapsing polychondritis

Patients with relapsing polychondritis (RP) and airway stenosis have difficulty performing conventional spirometry that requires maximum forced expiration. We report a patient with RP who showed progressive severe bronchial stenosis on three-dimensional computed tomography (3D-CT) and impulse oscillation (IOS) with 3D color imaging using a Mostgraph®. The forced oscillation technique using IOS allows within-breath evaluation without forced expiration. A 68-year-old man who had RP presented with dyspnea due to stenosis of the trachea and left main bronchus (lt. mb). Stenting was performed twice in two years. Chest 3D-CT revealed a marked difference in the extent of bronchial collapse during expiration compared with inspiration. The forced expiratory volume in 1 second (FEV1.0), reactance at 5Hz (X5), resonant frequency (Fres), and integrated low frequency reactance area (ALX) measured by IOS showed temporary improvement after placement of the first stent, but respiratory resistance at 5Hz (R5) and 20Hz (R20) remained poor. 3D color images of respiratory resistance obtained with a Mostgraph® already showed high values at the time of diagnosis, resembling the features of chronic obstructive disease (COPD). 3D color images were helpful for interpreting the changes of IOS parameters during the clinical course. In conclusion, 3D-CT in inspiration/expiration and noninvasive IOS with 3D color imaging are useful for assessing airway stenosis in RP while reducing the burden of repeated spirometry.

A novel approach inducing transplant tolerance by activated invariant natural killer T cells with costimulatory blockade

Invariant natural killer T (iNKT) cells are one of the innate lymphocytes that regulate immunity, although it is still elusive how iNKT cells should be manipulated for transplant tolerance. Here, we describe the potential of a novel approach using a ligand for iNKT cells and suboptimal dosage of antibody for CD40-CD40 ligand (L) blockade as a powerful method for mixed chimerism establishment after allogenic bone marrow transplantation in sublethally irradiated fully allo recipients. Mixed-chimera mice accepted subsequent cardiac allografts in a donor-specific manner. High amounts of type 2 helper T cytokines were detected right after iNKT cell activation, while subsequent interferon-gamma production by NK cells was effectively inhibited by CD40/CD40L blockade. Tolerogenic components, such as CD11c(low) mPDCA1(+) plasmacytoid dendritic cells and activated regulatory T cells (Tregs) expressing CD103, KLRG-1 and PD-1, were subsequently augmented. Those activating Tregs seem to be required for the establishment of chimerism because depletion of the Tregs 1 day before allogenic cell transfer resulted in a chimerism brake. These results collectively suggest that our new protocol makes it possible to induce donor-specific tolerance by enhancement of the innate ability for immune tolerance in place of the conventional immunosuppression.

'I-shaped' sign in the upper mediastinum: a novel potential marker for antenatal diagnosis of d-transposition of the great arteries

OBJECTIVES

To investigate the 'I-shaped' sign as a novel echocardiographic marker for antenatal diagnosis of d-transposition of the great arteries (dTGA) in routine cardiac examination, and to compare its prevalence in fetuses with dTGA, those with other congenital heart diseases (CHDs) and those with normal structural hearts.

METHODS

This retrospective evaluation involved 1134 fetuses undergoing echocardiography to screen for CHD over a 4-year period. I-shaped sign was defined as the characteristic appearance of the aortic arch, resembling the letter 'I', from the most anterior to the most posterior point of the descending aorta visible in the three vessels and trachea view. The frequency of this sign was evaluated in cases with dTGA, those with other cardiac defects and those with normal cardiac structures.

RESULTS

CHD was diagnosed in 671 (59.1%) cases, of which 31 (4.6%) had dTGA. I-shaped sign was observed in 30/31 (96.8%) cases of dTGA, compared with 31/640 (4.8%) cases with other cardiac anomalies, which included single ventricle with pulmonary atresia or severe pulmonary stenosis, hypoplastic left heart syndrome with aortic atresia, corrected transposition of the great arteries, and double outlet right ventricle with malposition of the great arteries. I-shaped sign was detected significantly more frequently in the dTGA group compared with the normal group and with the other CHDs group (both P < 0.001) and had 96.8% sensitivity and 97.1% specificity for diagnosis of dTGA. Importantly, I-shaped sign was never observed in fetuses with structurally normal hearts.

CONCLUSIONS

Detection on echocardiography of an extremely long vessel with a marked I-shape should raise suspicion of cardiac anomaly, especially dTGA. This marker may therefore aid in the prenatal diagnosis of dTGA during routine ultrasound examination.

SH2-containing inositol 5'-phosphatase 2 selectively impairs hypothalamic insulin signalling and regulation of food intake in mice

SH2-containing inositol 5'-phosphatase 2 (SHIP2) is a lipid phosphatase that negatively regulates the metabolic signalling of insulin in peripheral tissues; however, the expression of SHIP2 in the hypothalamus and its functional roles are largely unknown. In the present study, immunohistochemical analysis demonstrated that SHIP2 protein exists in neuronal cells expressing neuropeptide Y and pro-opiomelanocortin in the arcuate nucleus of the hypothalamus in C57BL/6J mice. Interestingly, the expression levels of SHIP2 in the hypothalamus were elevated in aged C57BL/6J mice and diabetic db/db mice. To clarify the significance of the increased expression of SHIP2 in the hypothalamus, we examined the central effects of insulin and leptin in transgenic mice overexpressing SHIP2 (SHIP2-Tg). Accumulation of phosphatidylinositol (3,4,5)-trisphosphate and phosphorylation of Akt in the hypothalamus, induced by i.c.v. injection of insulin, were attenuated in SHIP2-Tg compared to wild-type mice, whereas leptin-induced phosphorylation of signal transducer and activator of transcription 3 in the hypothalamus was comparable between them. The suppression of food intake after i.c.v. administration of insulin (but not leptin) was attenuated consistently in SHIP2-Tg. In addition, SHIP2-Tg showed increased food consumption after starvation and become heavier with visceral fat accumulation than wild-type mice, despite normal levels of oxygen consumption and spontaneous movement. These results suggest that SHIP2 contributes to the regulation of food intake mainly via the attenuation of insulin signalling in the hypothalamus of mice.

The effects of long-term exposure to ozokerite mainly consisting of an aliphatic series of hydrocarbons using F344 rats

Combined chronic toxicity and carcinogenicity studies of ozokerite (OZK), a natural wax substance used as a food additive for a gum base, were performed in male and female F344 rats. Dietary concentrations of 0%, 0.05%, 0.1% and 0.2% OZK were applied in a 52-week chronic toxicity study and 0%, 0.1% and 0.2% in a 104-week carcinogenicity study. In the chronic toxicity study, treatment with OZK caused a xenobiotic reaction against absorbed OZK, including formation of histiocytosis and granulomas with crystalline material in many organs in all of the treated males and females. Particularly in the liver, granulomatous inflammation was accompanied by hepatocellular vacuolation and changes in the serum biochemical parameters indicative of hepatic disorder. The number and area of glutathione S-transferase placental form (GST-P) positive foci were increased in all of the treated groups of both sexes, suggesting the proliferative effect of OZK. In the carcinogenicity study, the incidence of hepatocellular adenoma and the total tumor incidence in the liver of all of the treated males were significantly increased compared with the controls. In conclusion, long-term exposure to OZK caused systemic chronic inflammation due to a foreign body response. OZK was weakly carcinogenic in the liver of male F344 rats.