Clinical significance of a basophil activation test for Japanese beekeepers naturally sensitized to honey bee venom

BACKGROUND

The basophil activation test (BAT) has high sensitivity and specificity for diagnosing Hymenoptera venom allergy and is useful for predicting the clinical sensitivity of bee venom-allergic patients after venom immunotherapy. Patients sensitized to Hymenoptera venom are at risk for systemic reactions (SRs) to subsequent stings. Therefore, a tool that can predict the occurrence of SRs and the severity of Hymenoptera stings is needed.

OBJECTIVE

We performed BATs on Japanese beekeepers naturally sensitized to honey bee venom (HBV) and analyzed the positive threshold concentration for the occurrence of SRs following honey bee stings (HBS).

METHODS

Sixty-one beekeepers were interviewed and blood samples were taken. Data including history of HBS and the occurrence and severity of SRs to HBS were recorded. Blood samples were exposed to HBV-specific IgE antibodies (sIgE) and BAT was performed. Participants with HBV-sIgE ≥ class 1 were considered sensitized to HBV. The positive threshold for BAT scored as 0.0001, 0.001, 0.01, 0.1, and 1 μg/ml was classified as classes 5, 4, 3, 2, and 1, respectively. Samples negative at 1 μg/ml were classified as class 0.

RESULTS

About 40% of beekeepers with a positive BAT threshold ≤ 0.1 μg/ml had SRs after HBS. The mean score of the BAT positivity threshold for beekeepers who developed SRs was significantly lower than that for beekeepers with no history of SRs (2.6 ± 0.8 vs 1.4 ± 1.1, P < 0.01).

CONCLUSION

Analysis of the positive threshold of BAT in Japanese beekeepers naturally sensitized to HBV may be a useful tool for predicting the occurrence of SRs.

Differences and similarities in cytokine profiles of macrophage activation syndrome in systemic lupus erythematosus and adult-onset Still's disease

To clarify the differences and similarities in the cytokine profiles of macrophage activating syndrome (MAS) between systemic lupus erythematosus (SLE) and adult-onset Still's disease (AOSD). The study participants included 9 patients with MAS-SLE, 22 with non-MAS-SLE, 9 with MAS-AOSD, and 13 with non-MAS-AOSD. Serum cytokine levels were measured using a multiplex bead assay. Cytokine levels were compared between patients with SLE and AOSD with/without MAS. Moreover, cytokine patterns were examined using principal component analysis (PCA) and cluster analysis. IL-6, IL-8, IL-18, and TNF-α levels were elevated in patients with SLE and AOSD. IFN-α levels were elevated in SLE, whereas IL-1β and IL-18 levels were elevated in AOSD. In SLE, IFN-α and IL-10 levels were higher in MAS than in non-MAS and controls. PCA revealed distinctive cytokine patterns in SLE and AOSD, SLE with IFN-α and IP-10, AOSD with IL-1β, IL-6, and IL-18, and enhanced cytokine production in MAS. PCA and cluster analysis showed no differences in cytokine patterns between the MAS and non-MAS groups. However, serum ferritin levels were correlated with IFN-α levels in SLE. Cytokine profiles differed between SLE and AOSD but not between MAS and non-MAS. MAS is induced by the enhancement of underlying cytokine abnormalities rather than by MAS-specific cytokine profiles. Type I IFN may be involved in MAS development in patients with SLE.

The role of anti-elastin antibodies in a mouse model of asthma

BACKGROUND

The role of anti-elastin antibody (Ab) in the lung is unclear, although they may be involved in chronic obstructive pulmonary disease (COPD). Recently, increased anti-elastin Ab levels were reported in asthma.

OBJECTIVE

To elucidate the role of anti-elastin Ab in asthma, we created a murine asthma model. Anti-elastin Ab in the airway was neutralized by intratracheal administration of elastin peptide, and the inhibitory effects of anti-elastin Ab on airway remodeling were evaluated.

METHODS

BALB/c mice were immunized with ovalbumin (OVA) on days 0 and 14. After immunization, the mice received booster OVA via inhalation twice per week for 9 weeks, and bronchoalveolar lavage fluid (BALF) and lung tissues were evaluated.

RESULTS

In lung tissues, airway remodeling occurred after 9 weeks of OVA sensitization. Peak levels of anti-elastin Ab and eosinophils in BALF were detected after 3 weeks of OVA sensitization. Anti-elastin Ab and eosinophil levels in BALF were significantly reduced after 3 weeks by the neutralization of anti-elastin Ab. Peak transforming growth factor-β1 levels in BALF were detected at 3 weeks after OVA sensitization and were significantly reduced by the neutralization of anti-elastin Ab. Airway remodeling in lung tissues was also significantly inhibited by the neutralization of anti-elastin Ab.

CONCLUSIONS

In our murine asthma model, anti-elastin Ab was recruited to the airway by OVA-induced allergic inflammation. Airway remodeling was inhibited by the neutralization of anti-elastin Ab. Anti-elastin Ab may contribute to the progression of airway remodeling.

Elevation of anti-elastin antibody in patients with asthma

BACKGROUND

It is often difficult to differentiate between asthma and chronic obstructive pulmonary disease (COPD), and useful biomarkers are needed for accurate diagnosis.

OBJECTIVE

We evaluated anti-elastin antibody to identify useful biomarkers for differentiating between a diagnosis of asthma and COPD.

METHODS

Patients with asthma (male to female ratio = 10/13; mean age, 67.3 years), COPD (16/0; 74.8 years) and controls (8/4; 72.3 years) were enrolled. Samples from sputum and serum were collected and levels of anti-elastin Ab were measured.

RESULTS

The levels of anti-elastin Ab in sputum were significantly higher in asthma (11.4 ± 7.16 μg/mL) than in COPD (5.82 ± 5.16 μg/mL; P < 0.01), and serum levels in asthma (67.4 ± 29.7 μg/mL) were also significantly higher than in COPD or controls (45.0 ± 12.8 μg/mL; P < 0.05, 38.6 ± 10.4 μg/mL; P < 0.01, respectively). Anti-elastin Ab in sputum showed a positive correlation with smoking in asthma (r2 = 0.218, P < 0.05). However, no significant differences were observed in the levels of anti-elastin Ab and eosinophils, asthma phenotypes, inhaled corticosteroids, or severity in patients with asthma. Elastin was strongly expressed under the airway basement membrane in asthma compared with COPD or the healthy control.

CONCLUSIONS

Anti-elastin Ab in sputum could be a useful biomarker for COPD and asthma in ever-smokers. In asthma, anti-elastin Ab was recruited to the airways by both airway allergic inflammation and smoking, and it may contribute to the progression of airway remodeling via autoimmune inflammation, but not emphysema, in COPD.

Effect of inhaled corticosteroids on bone mineral density in patients with asthma

BACKGROUND

Inhaled corticosteroids (ICS) are a safe treatment for asthma. However, at higher doses, ICS use has been reported to inhibit adrenocortical function.

OBJECTIVE

This study aimed to evaluate the effect of ICS on bone mineral density (BMD) in adult patients with asthma.

METHODS

Ultrasonic bone densitometry was performed in 40 patients (14 men, 26 women, mean age 61.2 years, mean duration of asthma 6.19 years) who were receiving ICS for asthma, and the whole bone density, thickness of cortical bone, and density of cancellous bone of the radius was measured. The age-matched mean was set as 100%. Lifetime cumulative dose of ICS was calculated using all past prescriptions.

RESULTS

No significant correlations were observed between lifetime cumulative ICS dose and whole bone density (r² = 0.011), cortical bone thickness (r² = 0.022), and cancellous bone density (r² = 0.004). No significant differences were observed between lower and higher lifetime cumulative ICS dose among these BMD parameters (104% vs 97%, 103% vs 99%, and 106% vs 91%, respectively). No significant correlations or differences in lifetime cumulative ICS dose were observed by asthma severity, asthma duration, and pulmonary function. Also, serum markers of bone metabolism showed no significant correlations or differences with lifetime cumulative ICS dose.

CONCLUSIONS

In the entire study population, long-term ICS use was safe and was not associated with an increased risk of osteoporosis.

Th2 cell differentiation from naive CD4+ T cells is enhanced by autocrine CC chemokines in atopic diseases

BACKGROUND

Chemokines are involved not only in regulating leucocyte recruitment, but also in other activities. However, functions other than cell recruitment remain poorly understood. We have already shown that the production of CC chemokine ligand (CCL)17 and CCL22 by antigen-stimulated naïve CD4⁺  T cells was higher in asthmatic patients than in healthy controls. However, the role of these chemokines in stimulated naïve CD4⁺ T cells remains unclear.

OBJECTIVE

To clarify the biological function of CCL17 and CCL22 on naïve CD4⁺ T, we examined effects of these two chemokines on naïve CD4⁺ T cells expressing CC chemokine receptor (CCR)4 (a receptor for CCL17 and CCL22) during differentiation of Th2 cells in asthmatic patients as allergic subjects.

METHODS

Naïve CD4⁺ T cells were prepared from healthy controls and patients with asthma. We analysed effect of CCL17 and CCL22, and blocking their receptor on differentiation of Th2 cells.

RESULTS

Production of CCL17 and CCL22 by activated naive CD4⁺ T cells under Th2 condition was much more in asthmatic patients than in healthy controls. Proliferation and survival of the Th2 differentiating cells and restimulation-induced IL-4 production were much greater in asthmatic patients than in healthy controls. These cell biological phenomena were inhibited by blockade of CCR4. The biological effects of exogenous CCL17 and CCL22 were apparently observed in both healthy controls and asthmatic patients. The effectiveness of these chemokines on naïve CD4⁺ T cells from healthy controls was stronger than those from asthmatic patients. We found that thymic stromal lymphopoietin (TSLP), a Th2 promoting chemokine, is involved in the activation of CD4⁺ naïve T cells via production of CCL17 and CCL22.

CONCLUSIONS AND CLINICAL RELEVANCE

These data suggest that CCL17 and CCL22 produced by TSLP-primed naïve CD4⁺ T cells in asthma might contribute to an increase in Th2 cells via autocrine loops.

Allergic TH2 Response Governed by B-Cell Lymphoma 6 Function in Naturally Occurring Memory Phenotype CD4+ T Cells

Transcriptional repressor B-cell lymphoma 6 (Bcl6) appears to regulate T_H2 immune responses in allergies, but its precise role is unclear. We previously reported that Bcl6 suppressed IL-4 production in naïve CD4⁺ T cell-derived memory T_H2 cells. To investigate Bcl6 function in allergic responses in naturally occurring memory phenotype CD4⁺ T (MPT) cells and their derived T_H2 (MPT_H2) cells, Bcl6-manipulated mice, highly conserved intron enhancer (hcIE)-deficient mice, and reporter mice for conserved noncoding sequence 2 (CNS2) 3′ distal enhancer region were used to elucidate Bcl6 function in MPT cells. The molecular mechanisms of Bcl6-mediated T_H2 cytokine gene regulation were elucidated using cellular and molecular approaches. Bcl6 function in MPT cells was determined using adoptive transfer to naïve mice, which were assessed for allergic airway inflammation. Bcl6 suppressed IL-4 production in MPT and MPT_H2 cells by suppressing CNS2 enhancer activity. Bcl6 downregulated Il4 expression in MPT_H2 cells, but not MPT cells, by suppressing hcIE activity. The inhibitory functions of Bcl6 in MPT and MPT_H2 cells attenuated allergic responses. Bcl6 is a critical regulator of IL-4 production by MPT and MPT_H2 cells in T_H2 immune responses related to the pathogenesis of allergies.

Molecular biological analysis in a patient with multiple lung adenocarcinomas

The utility of molecular biological analysis in lung adenocarcinoma has been demonstrated. Herein we report a rare case presenting as multiple lung adenocarcinomas with four different EGFR gene mutations detected in three lung tumors. After opacification was detected by routine chest X-ray, the patient, a 64-year-old woman, underwent chest computed tomography which revealed a right lung segment S4 ground-glass nodule (GGN). Follow-up computed tomography revealed a 42 mm GGN nodule with a 26 mm nodule (S6) and a 20 mm GGN (S10). Histopathology of resected specimens from the right middle and lower lobes revealed all three nodules were adenocarcinomas. Four EGFR mutations were detected; no three tumors had the same mutations. Molecular biological analysis is a promising tool for the diagnosis of primary tumors in patients with multiple lung carcinomas of the same histotype, enabling appropriate treatment.

Case report of multiple pustules of the bilateral lower limbs caused by a granulocyte colony-stimulating factor-producing solid pseudopapillary tumour of the pancreas

Here we report a rare case of neutrophilic dermatoses related to a granulocyte colony-stimulating factor (G-CSF)-producing solid pseudopapillary tumour (SPT). The patient was a 39-year-old woman presenting with scattered pustules and crusts of the palms, heels and thighs and plaques of the bilateral lower legs. The skin biopsy revealed dense neutrophil infiltration in the epidermis to the dermis. A pancreatic head tumour was detected using computed tomography. A pathological examination of the resected specimen suggested an SPT. As the skin eruption promptly disappeared after SPT resection, we hypothesized that SPT secretes growth factors including epidermal growth factor (EGF) and G-CSF. The SPT cells stained positive for both EGF and G-CSF tumour cells. The serum levels of interleukin (IL)-6 and IL-10 and tumour necrosis factor-α were within normal limits before and after the SPT resection. In contrast, the serum IL-8, EGF and G-CSF levels decreased after the SPT resection. This is a rare case of neutrophilic dermatoses related to a G-CSF-producing SPT. The present case suggests that physicians should be aware that a G-CSF-producing tumour is a differential diagnosis to consider in patients with unusual aseptic pustulosis.

Transcriptional repression of p27 is essential for murine embryonic development

The Nczf gene has been identified as one of Ncx target genes and encodes a novel KRAB zinc-finger protein, which functions as a sequence specific transcriptional repressor. In order to elucidate Nczf functions, we generated Nczf knockout (Nczf−/−) mice. Nczf−/− mice died around embryonic day 8.5 (E8.5) with small body size and impairment of axial rotation. Histopathological analysis revealed that the cell number decreased and pyknotic cells were occasionally observed. We examined the expression of cell cycle related genes in Nczf−/− mice. p27 expression was increased in E8.0 Nczf−/− mice compared to that of wild type mice. Nczf knockdown by siRNA resulted in increased expression of p27 in mouse embryonic fibroblasts (MEFs). Furthermore, p27 promoter luciferase reporter gene analysis confirmed the regulation of p27 mRNA expression by Nczf. Nczf−/−; p27−/− double knockout mice survived until E11.5 and the defect of axial rotation was restored. These data suggest that p27 repression by Nczf is essential in the developing embryo.

Improved sensitivity to venom specific-immunoglobulin E by spiking with the allergen component in Japanese patients suspected of Hymenoptera venom allergy

BACKGROUND

Ves v 5 and Pol d 5, which constitute antigen 5, are recognized as the major, most potent allergens of family Vespidae. Several studies have reported the diagnostic sensitivity of the novel recombinant (r)Ves v 5 and rPol d 5 allergens in routine clinical laboratory settings by analyzing a group of Vespula and Polistes venom-allergic patients. In this study, we analyzed the sensitivity to venom specific (s)IgE by spiking with rVes v 5 and rPol d 5 in Japanese patients suspected of Hymenoptera venom allergy.

METHODS

Subjects were 41 patients who had experienced systemic reactions to hornet and/or paper wasp stings. Levels of serum sIgE against hornet and paper wasp venom by spiking with rVes v 5 and rPold d 5, respectively, as improvement testing, compared with hornet and paper wasp venom, as conventional testing, were measured by ImmunoCAP.

RESULTS

Of the 41 patients, 33 (80.5%) were positive (≥0.35 UA/ml) for hornet and/or paper wasp venom in conventional sIgE testing. sIgE levels correlated significantly (P < 0.01) between hornet (R = 0.92) or paper wasp venom (R = 0.78) in improvement testing and conventional testing. To determine specificity, 20 volunteers who had never experienced a Hymenoptera sting were all negative for sIgE against these venoms in both improvement and conventional testing. Improved sensitivity was seen in 8 patients negative for sIgE against both venoms in conventional testing, while improvement testing revealed sIgE against hornet or paper wasp venom in 5 (total 38 (92.7%)) patients.

CONCLUSIONS

The measurement of sIgE following spiking of rVes v 5 and rPol d 5 by conventional testing in Japanese subjects with sIgE against hornet and paper wasp venom, respectively, improved the sensitivity for detecting Hymenoptera venom allergy. Improvement testing for measuring sIgE levels against hornet and paper wasp venom has potential for serologically elucidating Hymenoptera allergy in Japan.

Reticulocyte hemoglobin content as a marker of iron status in patients receiving maintenance hemodialysis

Background. Patients with renal anemia who show a poor response to erythropoietin might have iron insufficiency. Reticulocyte hemoglobin content (CHr) was measured in hemodialysis patients, and its potential as a marker for iron status was assessed by comparing CHr with ordinary markers. Methods. Ninety-one patients receiving maintenance hemodialysis were enrolled. Venous sampling was performed twice, at a 3-month interval. During the interval, none of the patients received any iron agent and there was no alteration in their erythropoietin doses. CHr was measured with an automated blood cell counter. Simultaneously, ordinary markers for iron status, such as hematocrit (Ht), mean hemoglobin content (CH), serum iron (Fe), ferritin (Fr), and transferrin saturation (TSAT), were measured. CHr was compared with these markers. Results. CHr randed from 24.1 to 34.7 pg, with a mean of 31.0 pg. CHr correlated with CH (P < 0.001), Fr (P < 0.01), Fe (P < 0.001), and TSAT (P < 0.001), but not with Ht. When patients were divided into two groups according to the CHr : CH ratio (CHr : CH ≧ 1 and CHr : CH < 1), there was no difference in any parameter between the two groups in the first measurement. In the second measurement, done after a 3-month interval, patients with CHr : CH ≧ 1 showed significantly higher values for CHr (P < 0.001), CH (P < 0.01), Fe (P < 0.05), and TSAT (P < 0.05) than patients with CHr : CH < 1. Conclusions. It was suggested that the CHr : CH ratio would predict changes in the state of iron supply. CHr might be a potential marker for monitoring renal anemia.

Plant homeodomain finger protein 11 promotes class switch recombination to IgE in murine activated B cells

BACKGROUND

Polymorphisms of the Plant homeodomain finger protein 11 (PHF11) are strongly associated with high serum IgE levels and clinical severity of atopic patients. However, the precise mechanism has not been fully elucidated. We investigated the role of Phf11 in class switch recombination (CSR) to IgE by activated B cells.

METHODS

We generated Phf11 transgenic (Lckd-Phf11-Tg) mice that express the exogenous murine Phf11 in lymphocytes under the control of distal Lck promoter. We examined IL-4-induced CSR to IgE in activated Lckd-Phf11-Tg B cells in vitro. We analyzed production of ovalbumin (OVA)-specific IgE and nose-scratching symptoms in Lckd-Phf11-Tg mice using an OVA-induced allergic rhinitis model.

RESULTS

The exogenous Phf11 promoted CSR to IgG1 and IgE in activated B cells with an increase in germ line transcript (GLT) γ1 and GLT ε expression. The exogenous Phf11 augmented transcriptional activity of the GLT γ1 and GLT ε promoters through permissive histone modifications and binding of NF-κB and STAT6. Furthermore, the exogenous Phf11 bound to the GLT ε promoter with increased binding of NF-κB. Silencing of the endogenous Phf11 reduced the frequency of CSR to IgE and GLT ε expression, but not to IgG1 or GLT γ1 expression, in activated B cells. In an allergic rhinitis model, Lckd-Phf11-Tg mice showed a significant increase in the production of OVA-specific IgE and the frequency of nose scratching.

CONCLUSION

Phf11 accelerates CSR to IgE in activated B cells by increasing the transcriptional activity of GLT ε promoter and contributes to the exacerbation of allergic responses. These findings provide a novel therapeutic target for allergic diseases.

Leukotriene C4 aggravates bleomycin-induced pulmonary fibrosis in mice

BACKGROUND AND OBJECTIVE

Synthesis of cysteinyl leukotrienes (cys-LT) is thought to cause inflammatory disorders such as bronchial asthma and allergic rhinitis. Recent reports have suggested that leukotriene C4 (LTC4 ) is an important regulator of pulmonary fibrosis. This study examined the effect of LTC4 in LTC4 synthase-overexpressed transgenic mice with bleomycin-induced pulmonary fibrosis. The function of lung-derived fibroblasts from transgenic mice was also investigated.

METHODS

Bleomycin was administrated to transgenic mice and wild-type (WT) mice by intratracheal instillation. Concentrations of interleukin (IL)-4 and -13, interferon-γ, and transforming growth factor (TGF)-β1 in bronchoalveolar lavage fluid were measured 1, 3, 7 and 14 days after the administration of bleomycin. Lung tissue was examined histopathologically on day 14. In addition, lung-derived fibroblasts from transgenic and WT mice were cultured for 7 days. Expression of TGF-β1 mRNA was measured by real-time polymerase chain reaction.

RESULTS

Both the pathological scores for pulmonary fibrosis (3.8 ± 0.4 vs 2.0 ± 0.1, P < 0.05) and the levels of IL-4 (12.1 ± 2.3 vs <7.8 pg/mL, P < 0.05), IL-13 (26.5 ± 5.2 vs <7.8 pg/mL, P < 0.01) and TGF-β1 (211.1 ± 30.2 vs 21.3 ± 1.2 pg/mL, P < 0.01) on day 14 were significantly greater in transgenic than in WT mice. Furthermore, the reduction of LTC4 by pranlukast hydrate, a cys-LT1 receptor antagonist, in fibroblasts from transgenic significantly (P < 0.05) decreased the expression of TGF-β1 mRNA (by ∼50%) compared with those from WT mice.

CONCLUSIONS

Overexpression of LTC4 , amplifies bleomycin-induced pulmonary fibrosis in mice. Our findings suggest a role for LTC4 in lung fibrosis.

[Lymph node metastasis in superficial squamous carcinoma of the esophagus]

The definition of early carcinoma of the esophagus has changed with time on the basis of new data. As from 2007 an early carcinoma is defined as an intramucosal carcinoma with or without metastasis. In the subclassification based on invasion depth, m1 and m2 squamous cell carcinomas have no metastasis and are considered curable by endoscopic resection alone, whereas less than 10% of m3 carcinomas and some 20% of sm1 squamous cell carcinomas have lymph node metastasis. In this article the relationship between various histopathological findings and the incidence of lymph node metastasis is reviewed. The m3 and sm1 superficial squamous cell carcinomas showing 0-I and 0-III types, large tumors over 50 mm in size or those showing vessel permeation have higher incidences of lymph node metastasis. In the field of gastrointestinal surgical pathology pathologists are now expected to not only diagnose the presence or absence of malignancy but also to investigate in detail many of the histological factors related to the prevalence of lymph node metastasis.

Wasp venom allergy: effect of anti-IgE antibody on wasp venom anaphylaxis in a mouse model

BACKGROUND

Although anti-IgE antibody (Ab) therapy was recently shown to be effective in patients with bronchial asthma, no study has reported the effect of IgE therapy in the prevention of wasp venom anaphylaxis. In this study, we used a mouse model of wasp venom allergy to investigate the effect of anti-IgE Ab on wasp venom anaphylaxis.

METHODS

We developed a mouse model of wasp venom allergy by intraperitoneally (i.p.) injecting wasp venom into BALB/c mice twice on experimental day (day) 0 and 7. On day 20, a group of mice received an i.p. injection of mouse anti-IgE Ab as a pretreatment, and another group received rat anti-IgG1 Ab. On day 21, the animals were challenged by i.p. injection of wasp venom, and 30 min later, body temperature was measured and serum levels of leukotriene (LT) B4 and LTC4 were determined using enzyme immunoassay.

RESULTS

The body temperature of mice treated with anti-IgE Ab and controls before and after wasp venom challenge was 37.8±0.2 vs 37.7± 0.3°C before challenge and 37.8±0.2 vs 37.1± 0.3°C after challenge, respectively, showing that anti-IgE Ab treatment significantly prevented body temperature from falling (p <0.05). Furthermore, anti-IgE Ab treatment reduced total serum IgE levels in the treated mice (42.2±15.9 pg/ml), compared with controls (105.9±23.1 pg/ml, p <0.05), and inhibited the secretion of LTC4 in the treated mice (32.0±18.8 pg/ml), but not in the controls (162.4±12.4 pg/ml, p <0.05), following challenge with wasp venom.

CONCLUSION

The results of the present study indicate that anti-IgE Ab treatment is an effective preventive measure against wasp venom-induced anaphylaxis.

ADAR1 protein induces adenosine-targeted DNA mutations in senescent Bcl6 gene-deficient cells

Somatic mutations accumulate in senescent cells. Bcl6, which functions as a transcriptional repressor, has been identified as a potent inhibitor of cell senescence, but a role of Bcl6 in the accumulation of somatic mutations has remained unclear. Ig class-switch recombination simultaneously induces somatic mutations in an IgM class-switch (Ig-Sμ) region of IgG B cells. Surprisingly, mutations were detected in the Ig-Sμ region of Bcl6-deficient IgM B cells without class-switch recombination, and these mutations were mainly generated by conversion of adenosine to guanosine, suggesting a novel DNA mutator in the B cells. The ADAR1 (adenosine deaminase acting on RNA1) gene was overexpressed in Bcl6-deficient cells, and its promoter analysis revealed that ADAR1 is a molecular target of Bcl6. Exogenous ADAR1 induced adenosine-targeted DNA mutations in IgM B cells from ADAR1-transgenic mice and in wild-type mouse embryonic fibroblasts (MEFs). These mutations accumulated in senescent MEFs accompanied with endogenous ADAR1 expression, and the frequency in senescent Bcl6-deficient MEFs was higher than senescent wild-type MEFs. Thus, Bcl6 protects senescent cells from accumulation of adenosine-targeted DNA mutations induced by ADAR1.

Measurement of Hymenoptera venom specific IgE by the IMMULITE 3gAllergy in subjects with negative or positive results by ImmunoCAP

Background

Patients may receive negative results from a specific IgE (sIgE) test such as the ImmunoCAP (CAP) despite a documented history of systemic reaction to a Hymenoptera sting. Thus, further testing may be required using another serological method or venom skin prick tests to confirm allergy diagnosis and correct species.

Objective

To evaluate the sensitivity and the specificity of CAP and IMMULITE 3gAllergy (IMMULITE) for detecting sIgE to Paper wasp (WA) and Yellow Jacket (YJ) venoms using patient clinical history as the comparator.

Methods

Sera from 70 participants with a history of systemic reactions (SR) to WA and/or YJ stings were tested using CAP and IMMULITE. Fifty participants from this group had negative results on CAP. To assess specificity, sera from 71 participants who had never experienced either a WA or YJ sting were tested using CAP and IMMULITE. Fifty participants from this group tested positive using CAP.

Results

In participants with a history of systemic reaction to a Hymenoptera sting, yet who tested negative for WA and/or YJ sIgE according to CAP, the positivity rate according to IMMULITE was 20-42% using 0.10 IU_A/mL as the limit of detection (LoD), per the manufacturer's specification. When the LoD for CAP (0.35 IU_A/mL) was applied to the IMMULITE results, positivity according to IMMULITE was 14-26%. Overall, sensitivity, specificity, and agreement with SR were greater for IMMULITE than for CAP. For YJ: sensitivity (IMMULITE:CAP), 42.8%:28.5%; specificity, 53.5%:39.4%; agreement, 48.2%:34%. For WA, sensitivity (IMMULITE:CAP), 58.6%:28.5%; specificity, 49.3%:47.8%; agreement, 43.9%:38.3%.

Conclusion

The IMMULITE performed well for detecting sIgE to Hymenoptera venom

Riluzole-induced lung injury in two patients with amyotrophic lateral sclerosis

Riluzole has recently been proven as the first effective drug for the treatment of amyotrophic lateral sclerosis (ALS). We report two rare cases of lung injury caused by riluzole therapy in patients with ALS. Chest radiographs showed bilateral lower lobe, dorsal-dominant ground glass opacity, and/or consolidation. A drug lymphocyte stimulation test (DLST) of peripheral blood or bronchoalveolar lavage cells was positive for riluzole. Histopathological examination of lung biopsy specimens revealed lung injury without fungoid granuloma, vasculitis, or diffuse alveolar damage. To the best of our knowledge, this is the first report of riluzole-induced lung injury with positive DLST results.

Bcl6 in pulmonary epithelium coordinately controls the expression of the CC-type chemokine genes and attenuates allergic airway inflammation

BACKGROUND

There is synteny in the CC-type chemokine gene clusters between humans (CCL2/MCP-1, CCL7MCP-3, CCL11/eotaxin, CCL8/MCP-2, CCL13/MCP-4, and CCL1/I-309) and mice (CCL2, CCL7, CCL11, CCL12/MCP-5, CCL8, and CCL1).

OBJECTIVE

As many putative Bcl6/STAT-binding sequences are observed in the clusters, we examined the roles of a transcriptional repressor Bcl6 and the regional histone modification in the expression of these chemokine genes in pulmonary epithelium.

METHODS

We generated transgenic (Tg) mice carrying the Bcl6 or the dominant-negative (DN)-Bcl6 gene under the control of the surfactant protein C (SPC) promoter that induces the exogenous gene expression in the distal lung epithelium. For in vitro studies, A549, alveolar type II-like epithelial cell line transfected with the SPC-DN-Bcl6 gene were stimulated with IL-4+TNF-α, and Bcl6 or STAT6 binding to and histone modification of the cluster in the transfectants were analysed by chromatin immunoprecipitation assays. Tg mice sensitized with ovalbumin (OVA) were challenged with OVA inhalation. The amounts of mRNAs in each sample were analysed by quantitative RT-PCR.

RESULTS

The amount of Bcl6 bound to the cluster decreased in A549 cells stimulated with IL-4 and TNF-α, whereas STAT6 binding increased in association with regional histone H3-K9/14 acetylation and H3-K4 methylation. The expression of all chemokine genes in the gene cluster was augmented in activated A549 cells transfected with the DN-Bcl6 gene. We also induced allergic airway inflammation in Tg mice. Expression of the chemokine genes and infiltrated cell numbers in the lungs of these Tg mice with allergic airway inflammation were inversely correlated with the amount of Bcl6 in the lungs.

CONCLUSION AND CLINICAL RELEVANCE

Expression of the pulmonary epithelium-derived CC-type chemokine genes in the cluster is orchestrated by the conserved machinery related to Bcl6. Thus, Bcl6 in pulmonary epithelium may be a critical regulator for pathogenesis of various pulmonary inflammatory diseases.

Over-expression of the LTC4 synthase gene in mice reproduces human aspirin-induced asthma

BACKGROUND

The pathogenesis of aspirin-induced asthma (AIA) is presumed to involve the aspirin/non-steroidal anti-inflammatory drug (NSAID)-induced abnormal metabolism of arachidonic acid, resulting in an increase in 5-lipoxygenase (5-LO) metabolites, particularly leukotriene C(4) (LTC(4) ). However, the role of LTC(4) in the development of AIA has yet to be conclusively demonstrated.

OBJECTIVE

The aim of this study was to evaluate the contribution of the lipid product LTC(4) secreted by the 5-LO pathway to the pathogenesis of AIA.

METHODS

To evaluate antigen-induced airway inflammation, the concentrations of T-helper type 2 cytokine in bronchoalveolar lavage fluid (BALF) obtained from LTC(4) synthase-transgenic (Tg) and wild-type (WT) mice after challenge with ovalbumin were measured. Subsequently, the ex vivo and in vivo effects of the NSAID sulpyrine were investigated in these Tg and WT mice by measuring the secretion of LTC(4) from sulpyrine-treated BAL cells and the levels of LTC(4) in BALF following challenge with sulpyrine. Finally, the sulpyrine-induced airway response by the administration of pranlukast, an antagonist of the cysteinyl (cs)-LT1 receptor, was analysed.

RESULTS

The concentrations of IL-4, -5, and -13 in BALF from Tg mice were significantly higher than those in WT mice. In addition, sulpyrine augmented the secretion of LTC(4) in BALF and by BAL cells in Tg mice, but not in WT mice. Additionally, the increased airway resistance induced by sulpyrine could be reduced by treatment with pranlukast. Furthermore, the secretion of LTC(4) from mast cells, eosinophils, and macrophages was increased in the allergen-stimulated LTC(4) synthase gene Tg mice, even in the absence of sulpyrine, as well as in BAL cells after sulpyrine.

CONCLUSION AND CLINICAL RELEVANCE

The over-expression of the LTC(4) synthase in a mouse asthma model also replicates the key features of AIA. And our study supports that cys-LTs play a major role in the pathogenesis of AIA in patients with chronic asthma.

Prostaglandin D₂ and T(H)2 inflammation in the pathogenesis of bronchial asthma

Prostaglandin D₂ (PGD₂) is a major prostanoid, produced mainly by mast cells, in allergic diseases, including bronchial asthma. PGD₂-induced vasodilatation and increased permeability are well-known classical effects that may be involved in allergic inflammation. Recently, novel functions of PGD₂ have been identified. To date, D prostanoid receptor (DP) and chemoattractant receptor homologous molecule expressed on T(H)2 cells (CRTH2) have been shown to be major PGD₂-related receptors. These two receptors have pivotal roles mediating allergic diseases by regulating the functions of various cell types, such as T(H)2 cells, eosinophils, basophils, mast cells, dendritic cells, and epithelial cells. This review will focus on the current understanding of the roles of PGD₂ and its metabolites in T(H)2 inflammation and the pathogenesis of bronchial asthma.

CXCR4 expression on activated B cells is downregulated by CD63 and IL-21

CXCR4 expression is critical for localization of centroblasts in the dark zone of germinal centers (GCs), and centrocytes downregulate CXCR4 and thus leave the dark zone to reside in the light zone. However, mechanisms governing CXCR4 downregulation on centrocytes are not known. In this study, we show that the amount of intracellular CXCR4 in centroblasts was similar to that in centrocytes, suggesting differential control of CXCR4 protein expression in these GC B cells. Restimulation of activated B cells with IL-21, which is a major cytokine produced by T follicular helper cells, accelerated CXCR4 internalization by inducing endocytosis-related GRK6 expression. Although CXCR4 expression was downregulated on GC B cells by IL-21 stimulation, CXCR4(low) centrocytes developed in the spleens of IL-21R-deficient mice, suggesting other mechanisms for downregulation. The level of CD63 (which recruits CXCR4 to late endosome in CD4 T cells) in centrocytes was more than that in centroblasts and was strikingly elevated in activated Bcl6-deficient B cells. Bcl6, a transcriptional repressor, was detected on the chromatin of the CD63 gene in resting B cells, therefore CD63 is a molecular target of Bcl6. Downregulation of CD63 mRNA in activated Bcl6-deficient B cells by small interfering RNA upregulated CXCR4 expression on the B cells. Furthermore, addition of Bcl6 inhibitor to activated B cell cultures increased CD63 mRNA expression in (and downregulated CXCR4 expression on) those activated B cells. Thus, CXCR4 can be downregulated on activated B cells by IL-21-induced endocytosis and CD63-mediated endosomal recruitment, and these mechanisms may contribute to downregulation of CXCR4 on centrocytes.

Bcl6 is required for the development of mouse CD4+ and CD8α+ dendritic cells

Th2-type inflammation spontaneously shown in Bcl6-knockout (KO) mice is mainly caused by bone marrow (BM)-derived nonlymphoid cells. However, the function of dendritic cells (DCs) in Bcl6-KO mice has not been reported. We show in this article that the numbers of CD4(+) conventional DCs (cDCs) and CD8α(+) cDCs, but not of plasmacytoid DCs, were markedly reduced in the spleen of Bcl6-KO mice. Generation of cDCs from DC progenitors in BM cells was perturbed in the spleen of irradiated wild-type (WT) mice transferred with Bcl6-KO BM cells, indicating an intrinsic effect of Bcl6 in cDC precursors. Although cDC precursors were developed in a Bcl6-KO BM culture with Fms-like tyrosine kinase 3 ligand, the cDC precursors were more apoptotic than WT ones. Also p53, one of the molecular targets of Bcl6, was overexpressed in the precursors. The addition of a p53 inhibitor to Bcl6-KO BM culture protected apoptosis, suggesting that Bcl6 is required by cDC precursors for survival by controlling p53 expression. Furthermore, large numbers of T1/ST2(+) Th2 cells were naturally developed in the spleen of Bcl6-KO mice. Th2 skewing was accelerated in the culture of WT CD4 T cells stimulated with Ags and LPS-activated Bcl6-KO BM-derived DCs, which produced more IL-6 and less IL-12 than did WT DCs; the addition of anti-IL-6 Abs to the culture partially abrogated the Th2 skewing. These results suggest that Bcl6 is required in cDC precursors for survival and in activated DCs for modulating the cytokine profile.

An analysis of characteristics of patients with exacerbation of asthma in a large university hospital in Japan

BACKGROUND

Considerable progress has been made in the management of asthma with the increasing use of inhaled corticosteroids. However, asthma exacerbation remains a problem. To analyze the characteristics of patients with exacerbation of asthma who visited our hospital in order to better understand the risk factors for fatal asthma.

OBJECTIVES

We studied 100 patients who presented at Dokkyo Medical University Hospital (DMUH) with asthma exacerbation.

METHODS

Entry sheets were completed by physicians and questionnaires by patients.

RESULTS

Before the exacerbation, the severity was assessed as Step 1 in 46% of patients, Step 2 in 15%, Step 3 in 11%, and Step 4 in 18%. With regard to primary care physicians, 45% were treated at DMUH and 36% had no primary care physicians. Among the DMUH group, the largest proportion was aged 60-69 years and was in Step 4 category. According to asthma control test (ACT) scores, disease was poorly controlled in 83%. Patients with no primary care physician were most often aged 20-39 years (p < 0.01), and severity was assessed as Step 1 in 86% (p < 0.01). However, 44% were poorly controlled according to ACT (p < 0.05).

CONCLUSION

Patients could be classified into two groups: older patients with severe intractable asthma, treated by a specialist and younger patients considered to have mild asthma, half of whom had poorly controlled asthma and no primary care physician. Systems are needed that allow the emergency physicians to evaluate the need for regular treatment in patients with exacerbation because such patients often visit the hospital at night or on a non-working day.

A kelch family protein Nd1-L functions as a metastasis suppressor in cancer cells via Rho family proteins mediated mechanism

The BTB-kelch protein Nd1-L acts as an actin cytoskeleton stabilizer expressed ubiquitously in mouse tissues. We examined the effect of Nd1-L on cancer cell invasion and metastasis. Over-expression of Nd1-L in murine colon carcinoma cell line Colon 26 and murine melanoma cell line B16 resulted in suppression of pulmonary and liver metastasis after inoculation of these cells to syngeneric mice and in increased survival in an animal model. On the other hand, knock down of Nd1-L by RNA interference promoted metastasis ability of these cells. Increased expression of Nd1-L inhibited migration and Matrigel invasion capacity of cancer cell lines in vitro. Thus, Nd1-L expression inversely correlated with invasive and metastasis capacity of cancer cells. Furthermore, increased expression of Nd1-L in NIH3T3 cells inhibited growth factor induced activation of Rho family small GTPases such as Rho, Rac and cdc42. These results suggest that Nd1-L is involved in invasion and metastasis of cancer cells by regulating the actin cytoskeleton and Rho family proteins.

Effects of Th2 pulmonary inflammation in mice with bleomycin-induced pulmonary fibrosis

BACKGROUND AND OBJECTIVE

Leucocytes, especially lymphocytes and neutrophils, as well as alveolar macrophages, that infiltrate into the lung are involved in the development of pulmonary fibrosis. However, the role of T helper (Th)2-type inflammation, mediated by Th2 cells and eosinophils, in fibrosis remains unknown. Transgenic mice deficient in the transcriptional repressor, Bcl6, display an attenuation of Th2 cytokine production. We studied the effects of Th2-type pulmonary inflammation on bleomycin-induced pulmonary fibrosis using Bcl6 transgenic mice.

METHODS

Bleomycin was administered to ovalbumin (OVA)-sensitized Bcl6 transgenic and wild-type mice by intratracheal instillation during sequential OVA antigen challenge. Concentrations of transforming growth factor-beta1 in the BAL fluid were measured 2 weeks after bleomycin administration. At the same time lung tissue was examined histopathologically, and homogenized to assess collagen levels and Th1/Th2 cytokine mRNA expression.

RESULTS

Although OVA-sensitized, bleomycin-treated Bcl6 transgenic mice had markedly lower numbers of eosinophils in both BAL and lung tissue compared with OVA-sensitized, bleomycin-treated wild-type mice, the development of pulmonary fibrosis in response to bleomycin was similar in Bcl6 transgenic mice and wild-type mice.

CONCLUSION

These results suggest that Th2-dominant inflammation in the lung is not essential for the development of bleomycin-induced pulmonary fibrosis.

Prostaglandin D2 receptors DP and CRTH2 in the pathogenesis of asthma

Prostaglandin D2 (PGD2) is a major prostanoid produced mainly by mast cells in allergic diseases, including bronchial asthma. However, its role in the pathogenesis of asthma remains unclear. PGD2-induced vasodilatation and increased permeability are well-known classical effects that may facilitate transendothelial migration of inflammatory cells, such as eosinophils, mast cells, lymphocytes, and monocytes in allergic inflammation. These effects are initiated via a PGD2 receptor, D prostanoid receptor (DP), and are referred to as DP-mediated vasodilation-extravasation. Recently, novel functions of DP have been identified. Furthermore, a novel and different receptor of PGD2, CRTH2, has been discovered. To date, DP and CRTH2 have been shown to be major PGD(2)-related receptors that have pivotal roles in mediating allergic diseases by effects such as directly regulating the migration of inflammatory cells and controlling the production of cytokines and lipid mediators. Available evidence suggests that CRTH2 and DP may collaborate in allergic inflammation. This review focuses on the novel roles of DP and CRTH2 in the initiation and maintenance of allergy.

A role for Bcl6 in sequential class switch recombination to IgE in B cells stimulated with IL-4 and IL-21

IgE plays an important role in the pathogenesis of allergic diseases and high-affinity IgE memory B cells are differentiated from IgG1 B cells developed in germinal centers. Bcl6, a sequence specific transcriptional repressor, is highly expressed in germinal center B cells and suppresses expression of Cvarepsilon germline transcript. However, a role for Bcl6 in inhibition of the sequential class switching from IgG1 to IgE in germinal center B cells is not known. When splenic B cells from Bcl6-deficient (Bcl6-KO) and Bcl6-transgenic (Bcl6-TG) mice were stimulated with anti-IgM Ab and anti-CD40 Ab plus IL-4, IgG1(+)IgE(+) B cells were detected in Bcl6-KO B cell culture but not in Bcl6-TG B cell culture. Cgamma1 and Cvarepsilon germline transcript in Bcl6-KO B cells were induced earlier than those in wild-type (Bcl6-WT) B cells after stimulation. When activated B cells were simultaneously stimulated with IL-21, expression of Cgamma1 germline transcript in Bcl6-WT and Bcl6-KO B cells was enhanced by IL-21 stimulation, indicating that IL-21 is an enhancer of Cgamma1 expression induced by IL-4. The amount of Cgamma1 germline transcript in the Bcl6-KO B cells was more than that in the Bcl6-WT B cells. Conversely, IL-21 stimulation suppressed Cvarepsilon expression in the Bcl6-WT B cells. However, the suppression was not observed in the Bcl6-KO B cells, suggesting that the IL-21-mediated suppression of Cvarepsilon expression is due to Bcl6. Thus, Bcl6 controls the Cgamma1 and Cvarepsilon expression and stabilizes class switching to IgG1 in activated B cells simultaneously stimulated with IL-4 and IL-21.

Clinical outcome after endoscopic mucosal resection for esophageal squamous cell carcinoma invading the muscularis mucosae--a multicenter retrospective cohort study

BACKGROUND AND STUDY AIMS

Endoscopic mucosal resection (EMR) is now commonly indicated for esophageal squamous cell carcinoma (ESCC) within the lamina propria mucosa. However, EMR for ESCC that has invaded the muscularis mucosa is controversial because the risk of lymph node metastasis is not negligible. We conducted a multicenter retrospective cohort study to investigate the incidence of lymph node metastasis and survival after EMR for ESCC invading the muscularis mucosa.

PATIENTS AND METHODS

A total of 104 patients with 111 lesions invading the muscularis mucosa, were retrospectively studied at eight institutes. No patients exhibited evidence of metastasis of lymph nodes or distant organs prior to EMR. Overall and cause-specific survival rates were calculated from the date of EMR to the date of death or the most recent follow-up visit. Survival curves were plotted according to the Kaplan-Meier method.

RESULTS

In total, 86 patients (82.7%) who did not receive further treatment such as chemotherapy, irradiation therapy, chemoradiotherapy, or esophagectomy after EMR were followed up. Only two patients (1.9%) developed lymph node metastasis after EMR. With a median follow-up period of 43 months (range, 8-134 months), overall and cause-specific survival rates at 5 years after EMR were 79.5% and 95.0%, respectively.

CONCLUSIONS

EMR for ESCC that invades the muscularis mucosa has curative potential as a minimally invasive treatment option.

Identification of the consensus DNA sequence for Nczf binding

The Nczf gene, which is identified as a target gene of Ncx, encodes a novel Kruppel-associated box (KRAB) zinc finger protein, which functions as a sequence-specific transcriptional repressor. We generated a fusion protein of the zinc finger domain of Nczf and glutathione S-transferase to identify Nczf-binding consensus DNA sequences with random oligonucleotides of 15 and 35 bases. The consensus binding sequence of core nucleotides contains (A/T/C)CTTT(A/G)TTNT. In a gel mobility shift assay, the probe containing these sequences bound to the fusion protein. In silico analysis, these consensus sequences were found on regulatory regions of the endothelin receptor B and the microphthalmia-associated transcription factor genes, which are involved in neural crest development. These results suggest that Nczf functions as a sequence-specific transcription repressor to regulate neural crest cell development.

Early squamous cell carcinoma of the oesophagus: the Japanese viewpoint

In Japan, more than 90% of oesophageal malignancies are squamous cell carcinomas, and superficial and early carcinomas now account for about 40% and 20%, respectively, of all oesophageal carcinomas. Definition of early carcinoma has changed on the basis of new data. As of 2007, early carcinoma is defined as intramucosal carcinoma with or without metastasis. In the subclassification based on depth of cancer invasion, m1 and m2 carcinomas have no metastasis and are considered curable by endoscopic mucosal resection alone, whereas < 10% of m3 carcinomas and about 20% of sm1 carcinomas have lymph node metastasis. The relationship between various pathological findings and the incidence of lymph node metastasis has been reviewed. High-grade squamous dysplasia (squamous cell carcinoma in situ in Japan) requires surgical or endoscopic removal. Very minute carcinomas have recently been detected by magnifying endoscopy and/or narrowband imaging. Endocytoscopy could replace biopsy histopathological examination for diagnosis of oesophageal squamous cell carcinoma, and endocytoscopic diagnosis and endoscopic therapy may be performed simultaneously. As a result of advances in the development of endoscopes, pathologists are now expected to diagnose very minute lesions, < 1 mm in size, in the oesophagus.