Shengdao Xiong

Tumour necrosis factor alpha ‐308G/A polymorphism and risk of the four most frequent cancers: a meta‐analysis

The latest data show that breast, prostate, lung and colorectal cancer are the four most frequent cancers in both sexes worldwide. A number of molecular epidemiological studies have been conducted to examine the association between TNF alpha ‐308G/A and the risk of those cancers. However the results have been inconclusive or inconsistent. We then performed a meta‐analysis to derive a precise estimation of this association. We carried out a comprehensive search in Medline, EMBASE, OVID and Chinese Biomedical Literature Database for studies using related keywords. The inclusion criteria were (i) in English or Chinese; (ii) case–control study on this association; (iii) provide usable genotype frequencies; and (iv) sufficient published data for estimating an odds ratio (OR) with 95% confidence interval (CI). ORs and 95% CIs were calculated to assess the strength of this association under homozygote comparison (AA vs GG), heterozygote comparison (GA vs GG), dominant (AA/GA vs GG) and recessive (AA vs GA/GG) genetic model comparison. Thirty case–control studies with a total number of 16 507 cases and 19 749 controls were selected for analysis. Overall, no significant association was found between this polymorphism and the risk of total four cancers (GA vs GG: OR = 1.02, 95% CI = 0.91–1.14, P = 0.78). However, there was a significant association between this polymorphism and breast cancer risk in western populations (GA vs GG: OR = 0.91, 95% CI = 0.85–0.96, P = 0.002). This meta‐analysis also revealed that this polymorphism was not associated with susceptibility to the other three cancers.

The study of the ratio and distribution of Th17 cells and Tc17 cells in asthmatic patients and the mouse model

BACKGROUND Whether CD8+ IL-17-producing T cells, namely Tc17 cells, play a role in asthma has not been determined. The aim of this study was to evaluate and compare the frequency of peripheral blood Th17 cells and Tc17 cells in asthmatic patients. In addition, the number, ratio and distribution of Th17 cells and Tc17 cells in the lung tissue and splenocytes of asthmatic mice were also investigated. METHODS Th17 and Tc17 cells in the peripheral blood samples of asthmatic patients and in murine spleens were detected by flow cytometric analysis. Th17 and Tc17 cells in murine lung tissues were detected by double immuno-fluorescence stain. IL-17A levels in murine bronchoalveolar lavage were detected by ELISA. RESULTS The result of the flow cytometric analysis showed the percentage of Th17 cells among CD3+ T cell populations in patients with asthma was higher than that in healthy controls (P < 0.01), The percentage of Tc17 cells was also higher (P < 0.05). The percentages of Th17 and Tc17 cells in asthmatic mice were both much higher than that in control animals (P < 0.01). Frozen sections of lung tissue showed that the number of Th17 cells and Tc17 cells in the asthma group were all significantly higher than in the control group (P < 0.01). CONCLUSIONS Our findings suggest a functional disequilibrium of Th17 and Tc17 cell subsets in asthma that may contribute to the inflammatory process and provide novel insights into a hypothetical driving role of those cells in disease pathogenesis.

Analysis of CD4+ CD25+ regulatory T cells and Foxp3 mRNA in the peripheral blood of patients with asthma.

The changes of CD4+CD25+ regulatory T cells (CD4+CD25+ Treg) and Foxp3 mRNA in peripheral blood mononuclear cells (PBMCs) from patients with asthma were investigated in order to elucidate the possible roles of CD4+CD25+ Treg in the development of asthma. The peripheral blood samples were collected from 29 healthy controls (normal control group) and 78 patients with asthma which included 30 patients in exacerbation group, 25 patients in persistent group, and 23 patients in remission group. By using flow cytometry and RT-PCR, the CD4+CD25+ Treg ratio and Foxp3 mRNA in PBMCs were detected. The CD4+CD25+ Treg ratio and Foxp3 mRNA in PBMCs of exacerbation and persistent groups were lower than that of remission and normal control group (P<0.05). Although the CD4+CD25+ Treg ratio and Foxp3 mRNA of remission group also lower than that of normal control group, there was no significant difference between them (P>0.05). As compared with persistent group, exacerbation group had lower CD4+CD25+ Treg ratio and Foxp3 mRNA (P<0.05). It was indicated that the decrease of CD4+CD25+ Treg ratio and its function in PBMCs may be responsible for pathogenesis of asthma.

Administration of nonviral gene vector encoding rat β-defensin-2 ameliorates chronic Pseudomonas aeruginosa lung infection in rats

Beta‐defensin‐2 (BD‐2) plays an important role in host defense against pathogenic microbe challenge by its direct antimicrobial activity and immunomodulatory functions. The present study aimed to determine whether genetic up‐regulation of rat BD‐2 (rBD‐2) could ameliorate chronic Pseudomonas aeruginosa lung infection in rats.

The effects of antisense interleukin-4 gene transferred by recombinant adeno-associated virus vector on the airway remodeling in allergic rats

Background: Th2-derived cytokines, including interleukin-4 (IL-4), are considered to play an important role in the development of airway remodeling of asthma. Objectives: Our previous study has demonstrated that a recombinant adeno-associated virus containing antisense against IL-4 gene (rAAV-asIL4) vector could significantly suppress the expression of IL-4 protein and airway inflammation in the rat models of allergic asthma. In this study, we applied the rAAV-asIL4 vector to allergic rats to investigate the effects of anti-IL4 therapy on airway remodeling in allergic asthma. Methods: rAAV-asIL4 was used to infect the ovalbumin (OVA)-sensitized and challenged rats by tail-vein injection. IL-4 protein in bronchoalveolar lavage fluid (BALF) was detected by enzyme-linked immunosorbent assay. The number of eosinophils in BALF was counted. Transforming growth factor-beta1 (TGF-beta1) and TGF-beta2-positive cells in the peribronchial space were detected by immunohistochemical staining, and collagen deposition beneath the basement membrane was detected by Sirius red stain. The lung tissues were collected for histologic analysis of total bronchial wall area (WAt) and airway smooth muscle area (WAm). Results: rAAV-asIL4 significantly decreased IL-4 protein in BALF of OVA-sensitized and challenged rats. The number of eosinophils in BALF, the TGF-beta1 and TGF-beta2-positive cells in the peribronchial space were also suppressed. Moreover, the rAAV-asIL4 treatment inhibited the area of Sirius red staining in airways and the increase in WAt and WAm. Conclusion: These results suggest that rAAV-asIL4 may attenuate the airway remodeling process relevant to the inhibition of airway inflammation. This study provides elementary evidence for the potential utility of rAAV-asIL4 as an approach to gene therapy for asthmatic airway remodeling.

Lactoferrin-derived peptides and Lactoferricin chimera inhibit virulence factor production and biofilm formation in Pseudomonas aeruginosa.

Aims:  To investigate the bactericidal activity of lactoferrin‐derived peptides and a new LF‐derived peptides chimera (LFchimera) against P. aeruginosa and the influence on virulence factors of P. aeruginosa.

Expression of the Th1-Specific Cell-Surface Protein Tim-3 Increases in a Murine Model of Atopic Asthma

T-cell immunoglobulin- and mucin-domain-containing molecule-3 (Tim-3) is preferentially expressed on Th1-helper type T-cells and functions to repress the Th1-mediated immune response. However, the role of Tim-3 during the inflammatory pathogenesis of asthma remains unclear. This study determines the expression level of Tim-3 in CD4+ T-cells within the peripheral blood and bronchoalveolar lavage fluid (BALF) isolated from a murine model of atopic asthma and explores the potential role of Tim-3 during the inflammatory response. Mice were randomly divided into normal control, asthma day 1, and asthma day 7 groups, and peripheral blood T lymphocytes and BALF cells were collected. The ratio of Tim-3+/CD4+ cells among the total CD4+cell populations from peripheral blood and BALF was determined by flow cytometry, and the expression of the Tim-3 mRNA was determined by Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR). In contrast with the normal control group, the ratio of Tim-3+/CD4+:CD4+ cells and the level of Tim-3 mRNA in both the peripheral blood T lymphocytes and BALF cells among the asthma day 1 and asthma day 7 groups were significantly increased (p < 0.01), and those in the asthma day 7 group were higher than the asthma day 1 group (p < 0.05). There was also a positive correlation between the ratio of Tim-3+/CD4+:CD4+ detected in BALF and that the ratio detected in peripheral blood T lymphocytes (r = 0.84, p < 0.01). Therefore, the expression of Tim-3 is increased in CD4+ T-cells following airway challenge and likely affects asthma-induced inflammation by repressing the Th1-mediated immune response.

Primary pulmonary coccidioidomycosis in China

Coccidioidomycosis is a fungal infection endemic to south‐west USA, north Mexico and parts of Central and South America. We report here a case of primary pulmonary coccidioidomycosis in a previously healthy 14‐year‐old boy in China, which is considered a non‐endemic country. The patient had non‐specific symptoms of pulmonary infection, including fever, non‐productive cough and night sweats. Both spherules and endospores of Coccidioides immitis were seen histologically following transbronchial biopsy of a cavitary lesion. The patient was treated with amphotericin B and fluconazole. Follow up 6 months post discharge found that the patient made a good recovery.

The effect of Ginkgo Biloba Extract on the expression of PKCα in the inflammatory cells and the level of IL-5 in induced sputum of asthmatic patients

To investigate the effect of the Ginkgo Biloba Extract (GBE) on the asthma and examine its possible mechanisms, 75 asthma patients were divided into 4 groups and the patients were respectively treated with fluticasone propionate for 2 weeks or 4 weeks, or treated with fluticasone propionate plus GBE for 2 weeks or 4 weeks. Fifteen healthy volunteers served as healthy controls. Sputum inhalation with inhaling hypertonic saline (4%–5%) was performed. Lung ventilatory function and forced expiratory volume in one second (FEV1) were measured. The numbers of different cells in induced sputum were calculated. The expression of PKCα in the cells was immunocytochemically detected and the percentages of positive cells in different cells were counted. Interleukin-5 (IL-5) in sputum supernatants was detected with enzyme-linked immunosorbent assay. The percentage of eosinophils, lymphocytes, PKCα positive inflammatory cells and the concentration of IL-5 in asthmatic patients were higher than those in the controls (P<0.05), and the eosinophils, lymphocytes, positive expression of PKCα and the level of IL-5 were significantly decreased in asthmatic patients after they were treated with fluticasone propionate or fluticasone propionate plus GBE. However, they were still significantly higher than those of the controls. Compared to the group treated with glucocorticosteroid for 2 weeks, no significant decrease was found in the percentage of eosinophils, lymphocytes, PKCα positive inflammatory cells and the IL-5 in the supernatant of induced sputum. Compared with the group treated with glucocorticosteroid for 2 or 4 weeks, significant decrease in the same parameters was observed in the group treated with fluticasone propionate and GBE for 4 weeks. The IL-5 level in the supernatant of induced sputum was positively correlated with the percentage of PKCα-positive inflammatory cells and the percentage of eosinophils in the induced sputum in asthma patient groups respectively (n=150, r= 0.83, P<0.01; n=150, r=0.76, P<0.01). The FEV1 was negatively correlated with the percentage of PKCα-positive inflammatory cells and the IL-5 levels in supernatant of induced sputum in asthma patients respectively (n=150, r=−0.77, P<0.01; n=150, r= −0.64, P<0.01). It is concluded that GBE could significantly decrease the infiltration of inflammatory cells such as eosinophils and lymphocytes in the asthmatic airway and relieve the airway inflammation. GBE may decrease the activation of the PKCα in the inflammatory cells and thereby decrease the IL-5 level in induced sputum. GBE may be used as a complement to the glucocorticosteroid therapy for asthma.

Recombinant adeno-associated virus vector-mediated delivery of antisense interleukin-5 gene attenuates airway remodeling in allergic rats.

Background: Increasing evidence indicates that eosinophils contribute greatly to airway remodeling in asthma. Since interleukin-5 (IL-5) plays a critical role in the regulation of eosinophils in asthma, anti-IL-5 therapy may be a novel approach to inhibit airway remodeling in asthma. Objectives: In this study, we applied a recombinant adeno-associated virus vector-mediated antisense IL-5 gene delivery (rAAV-ASIL-5) system to investigate its effect on airway remodeling in ovalbumin (OVA)-sensitized and -challenged rats. Methods: rAAV-ASIL-5 was used to infect OVA-sensitized and -challenged rats. IL-5 protein in bronchoalveolar lavage fluid (BALF) was detected by ELISA. The eosinophils in BALF were counted. Transforming growth factor (TGF)-β1- and TGF-β2-positive cells in the peribronchial space were detected by immunohistochemical staining. Lung tissue was collected for Sirius red staining and histological analysis. Results: rAAV-ASIL-5 significantly decreased the level of IL-5 protein, the number of eosinophils in BALF and the numbers of TGF-β1- and TGF-β2-positive cells in the peribronchial space. The area of Sirius red staining in airways was also decreased. Moreover, the rAAV-ASIL-5 treatment inhibited the increase in total bronchial wall area and airway smooth muscle area. Conclusion: These results suggest that rAAV-ASIL-5-based gene therapy could be used to inhibit airway remodeling in allergic rats.