Skin inflammation exacerbates food allergy symptoms in epicutaneously sensitized mice

BACKGROUND

Cutaneous exposure to food antigen through impaired skin barrier has been shown to induce epicutaneous sensitization, thereby causing IgE-mediated food allergies.

OBJECTIVE

We examined whether skin barrier impairment following epicutaneous sensitization exacerbates food allergies.

METHODS

BALB/c mice were epicutaneously sensitized by repeated application of ovalbumin (OVA) to MC903-pretreated ear skin for 48 hours weekly and then intragastrically challenged with OVA. After the first oral challenge, the skin barrier was disrupted with topical application of MC903 or by tape-stripping. Mice were monitored for changes in body temperature and the occurrence of diarrhea after undergoing the second oral challenge. Serum levels of mouse mast cell protease-1 (mmcp1) and OVA-specific IgE, IgG1, IgG2a antibodies and OVA-specific IgA levels in intestinal lavage fluid were measured by ELISA. Tissue accumulation of eosinophils was determined histologically.

RESULTS

Epicutaneously sensitized mice developed anaphylaxis after intragastric challenge, as evidenced by diarrhea, decreased body temperature, and increased serum mmcp1 levels. Skin barrier disruption by MC903 treatment or tape-stripping exacerbated allergic reactions induced by oral challenge. MC903 treatment increased serum baseline and postchallenge mmcp1 levels. Topical pretreatment with dexamethasone alleviated allergic reactions that were exacerbated by MC903 treatment.

CONCLUSION

Even after eliminating exposure to the antigen, inflammation from skin barrier disruption can exacerbate the severity of food allergy symptoms. Serum baseline mmcp1 levels might be an effective marker for predicting the severity of antigen-induced allergic symptoms.

A Rapid in vivo Bioassay for the Carcinogenicity of Pesticides

Eight pesticides were tested in a bioassay based on the induction of preneoplastic lesions in the liver. Rats were given diethylnitrosamine intraperitoneally at 200 mg/kg bw and two weeks later were treated with pesticides for six weeks and then killed; all rats had a partial hepatectomy at week 3. Hepatocarcinogenic potential was assessed by comparing the number and area of glutathione s-transferase (placental form) -positive foci In the liver with those of controls given diethylnitrosamine alone. Positive results were seen with Chinomethionat, Phosmet and Propiconazole; the results obtained with Captan and Prochloraz were borderline; Benomyl, Daminozide and Folpet gave negative results. Our findings provide enough experimental evidence to indicate that great care should be exercised in the use of these compounds.

Enhancement of Satellite Cell Transplantation Efficiency by Leukemia Inhibitory Factor

BACKGROUND AND OBJECTIVES

Cell transplantation is a promising therapy for several muscle diseases, including Duchenne muscular dystrophy. Satellite cells are stem cells in skeletal muscle that provide an important cell source for transplantation therapy. However, culture of satellite cells in vitro causes them to lose their undifferentiated state, associated with reduced transplantation efficiency. It is therefore necessary to develop optimal culture conditions for maintaining the undifferentiated state of satellite cells.

METHODS

Primary satellite cells were cultured with or without leukemia inhibitory factor (LIF). The expression of undifferentiation and differentiation markers, and the transplantation efficiency were analyzed.

RESULTS

LIF-treated satellite cells showed increased expression of Pax7, and enhanced transplantation efficiency in a mouse model of Duchenne muscular dystrophy.

CONCLUSIONS

Our study showed that the treatment with LIF effectively maintained the undifferentiated state of satellite cells, and enhanced their transplantation efficiency. These results will contribute to the optimization of culture conditions for cell transplantation therapy.

Development of 2-D horn-antenna millimeter-wave imaging device (HMID) for the plasma diagnostics

The two-dimensional (2-D) Horn-antenna Millimeter-wave Imaging Device (HMID) has been developed for the O-mode Microwave Imaging Reflectometry (O-MIR) in the Large Helical Device (LHD). The detectable frequency range of the HMID is 23-33 GHz, which corresponds to the cutoff electron density of 0.8-1.5 × 10¹⁹ m^-3 in the O-MIR. The HMID is a 2-D imaging device that improves on the horn-antenna mixer array, which had been developed for the X-mode MIR in the LHD. In the HMID, the signal (RF) wave from the horn antenna is transmitted to the microstrip line by the finline transmitter, and this is mixed by the double-balanced-mixer with the local oscillation wave that is fed by a coaxial cable. By using the HMID, the MIR optical system can be significantly simplified.

A 60-GHz interferometer with a local oscillator integrated antenna array for divertor simulation experiments on GAMMA 10/PDX

In conventional multichannel/imaging microwave diagnostics of interferometry, reflectometry, and electron cyclotron emission measurements, a local oscillator (LO) signal is commonly supplied to a receiver array via irradiation using LO optics. In this work, we present a 60-GHz interferometer with a new eight-channel receiver array, called a local oscillator integrated antenna array (LIA). An outstanding feature of LIA is that it incorporates a frequency quadrupler integrated circuit for LO supply to each channel. This enables simple and uniform LO supply to the receiver array using only a 15-GHz LO source and a coaxial cable transmission line instead of using an expensive 60-GHz source, LO optics, and a waveguide transmission line. The new interferometer system is first applied to measure electron line-averaged density inside the divertor simulation experimental module (D-module) on GAMMA 10/PDX tandem mirror device.

Effects of protease inhibitors on LPS-mediated activation of a mouse macrophage cell line (J774)

Pretreatment (1 h) of a mouse macrophage-like cell line, J774, with the protease inhibitor, phenylalanine-chloromethyl ketone (PCK) or its structural analogue, tosylphenylalanine chloromethyl ketone (TPCK) was found to cause substantial inhibition of LPS-triggered activation of NF-κB. Pretreatment of cells with other types of protease inhibitors or their various structural analogues had no effect. PCK or TPCK appeared to exert its inhibitory effect by: (i) partially preventing LPS-triggered degradation of IκBα protein; (ii) preventing LPS-triggered nuclear translocation of NF-κB proteins (p50, RelA and Rel); and (iii) inhibiting the DNA-binding activities of NF-κB proteins. Pretreatment of cells with PCK or TPCK also resulted in the total or partial inhibition of LPS activatable (AP-1 or CREB) or constitutively-existing (Oct-1) transcription factors, but not of another constitutively-expressed transcription factor (SP-1). Pretreatment of J774 cells with PCK was found to substantially suppress LPS-induced expression of mRNAs specific for cytokine genes (TNFα, IL-1α and β, and IL-6), inducible nitric oxide synthase (iNOS) gene and IκBα gene, but not NF-κB1 p105 gene or β-actin gene. Furthermore, PCK pretreatment inhibited, in a dose-dependent manner, LPS-triggered production of nitric oxide production and tumoricidal activity.

Combination Treatment of Artificial Dermis and Basic Fibroblast Growth Factor for Skin Defects: A Histopathological Examination

This study examined a combination of artificial dermis and basic fibroblast growth factor (bFGF) to treat skin defects in clinical cases, and it histopathologically examined the effects on the conditions of recipient beds.

MATERIALS AND METHODS

The subjects were 11 patients with skin defects from burn ulcers or traumatic ulcers. In each subject, debridement was performed and subsequently artificial dermis was applied to the defect. The bFGF was used on 1 side (combination therapy) of the artificial dermis and not used on the other side (artificial dermis monotherapy). A histopathological examination was performed on the granulation tissue collected from the recipient bed. The authors also measured skin hardness 6 months after the skin graft.

RESULTS

Histologically, the combination therapy site had more extensive capillary angiogenesis than the monotherapy site. The combination therapy site also had capillary walls consisting of thick, large endothelial cells; fibroblast proliferation and activation; and more severe infiltration of inflammatory cells. Skin hardness after the graft was also much softer in the combination therapy.

CONCLUSION

The results suggest the usefulness of this combination therapy in the preparation of skin graft beds to improve skin hardness after skin grafts in clinical cases.

Quasi 3D ECE imaging system for study of MHD instabilities in KSTAR

A second electron cyclotron emission imaging (ECEI) system has been installed on the KSTAR tokamak, toroidally separated by 1/16th of the torus from the first ECEI system. For the first time, the dynamical evolutions of MHD instabilities from the plasma core to the edge have been visualized in quasi-3D for a wide range of the KSTAR operation (B0 = 1.7∼3.5 T). This flexible diagnostic capability has been realized by substantial improvements in large-aperture quasi-optical microwave components including the development of broad-band polarization rotators for imaging of the fundamental ordinary ECE as well as the usual 2nd harmonic extraordinary ECE.

Development of horn antenna mixer array with internal local oscillator module for microwave imaging diagnostics

A new antenna array is proposed in order to improve the sensitivity and complexity of microwave imaging diagnostics systems such as a microwave imaging reflectometry, a microwave imaging interferometer, and an electron cyclotron emission imaging. The antenna array consists of five elements: a horn antenna, a waveguide-to-microstrip line transition, a mixer, a local oscillation (LO) module, and an intermediate frequency amplifier. By using an LO module, the LO optics can be removed, and the supplied LO power to each element can be equalized. We report details of the antenna array and characteristics of a prototype antenna array.