Objective Prior reports suggested that infection with Helicobacter pylori was associated with respiratory diseases; pathogenetic mechanisms however, were not defined. We tested the hypothesis that VacA, an exotoxin of Helicobacter pylori, a gastric pathogen, was aspirated into the lung and could stimulate secretion of inflammatory cytokines by lung epithelial cells. Methods The presence of VacA was determined by immunohistochemistry in surgical lung biopsy tissue samples from 72 patients with interstitial pneumonia. The effects of VacA on A549 human alveolar epithelial adenocarcinoma cells and normal human bronchial epithelial cells were determined. After incubation with VacA, the secretions of cytokines were measured by Multiplex Luminex® Assays. Results VacA was detected with anti-VacA antibodies in bronchial epithelial cells and alveolar epithelial cells from 10 of 72 patients with interstitial pneumonia. VacA was more prevalent in lungs of patients with collagen vascular disease-associated interstitial pneumonia than in those of patients with idiopathic pulmonary fibrosis, nonspecific interstitial pneumonia and cryptogenic organizing pneumonia. Incubation of A549 cells and normal human bronchial epithelial cells with VacA for 24 h was cytotoxic, and resulted in vacuolation. VacA induced interleukin-8 production by A549 cells and normal human bronchial epithelial cells and interleukin-6 production by A549 cells. Based on multiplex screening, interleukin-8 and interleukin-6 were the primary secretory products induced by VacA. Conclusions Helicobacter pylori VacA is present in human lung and can induce interleukin-8 and interleukin-6 production by human lung cells. VacA could have a role in the pathogenesis of respiratory diseases by its cytotoxic effects and by inducing the secretion of interleukin-8 and interleukin-6 by targeted airway epithelial cells.

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To determine the expression of multidrug resistance‐associated protein (MRP) gene and its role in gastric and colon cancers, we analyzed 10 gastric and 10 colon non‐drug‐selected cell lines and a similar number of tissue samples of these cancers. We compared the expression of MRP and mdr1 mRNA in cell lines and tissues using reverse‐transcriptase polymerase chain reaction. In mdr1‐negative cells, the relationship between the level of MRP gene expression and sensitivity to anticancer drugs was examined. The effect of verapamil, an MRP‐modulating agent, was also examined in these cells. The expression of MRP gene in gastric cancer cell lines varied from a low to a high level, but mdr1 was not detected in any of these cell lines. Colon cancer cell lines expressed low to intermediate levels of MRP gene, and half of the cells co‐expressed low to high levels of mdr1. In tissue samples, the expression pattern of the two multidrug resistance (MDR) genes was broadly similar to that described for the cell lines, except that most of the gastric cancer tissue samples did express low levels of mdr1. No significant correlation was observed between the level of MRP gene expression and sensitivity to anticancer drugs in gastric and colon cell lines. However, verapamil significantly increased the sensitivity to etoposide, doxorubicin and vincristine in cells highly expressing MRP gene. Our results indicate that MRP gene may be important in conferring MDR in gastric and colon cancer cells.

Elevated plasma levels of HNPs were higher in AE-IP than in S-IP, but not specific enough to serve as candidate biomarkers of AE-IP. Further studies are needed to clarify the role of defensins in the pathogenesis of AE-IP.

Anti-PL-7 is an anti-tRNA synthetase antibody (ARS) and interstitial lung disease (ILD) is the most frequent complication of anti-PL-7-associated antisynthetase syndrome (ASS).However, the features of ILD have not been fully elucidated. The present study retrospectively compares seven and 15 patients who were positive for anti-PL-7 and anti-Jo-1 antibodies, respectively. The features of ILD did not significantly differ between the two groups, but the ratio of lymphocytes in bronchoalveolar lavage fluid was higher in the Jo-1, than in the PL-7 group. High-resolution computed tomography revealed nonspecific interstitial pneumonia in all patients in the PL-7 group and organizing pneumonia in four of the 15 patients in the Jo-1 group. These findings suggest that pulmonary complications slightly differ between patients expressing anti-PL-7 and anti-Jo-1 antibodies. Further studies are required to clarify the features of ILD associated with PL-7.