[Budesonide attenuates airway remodeling and modules the expression of Janus protein tyrosine kinase 1, and signal transducers and activators of transcription 6 in asthma: an experiment with mice].

OBJECTIVE: To investigate the effects of budesonide (BUD) on the airway remodeling and the expression of Janus protein tyrosine kinases 1 (JAK1) and signal transducer and activator of transcription 6 (STAT6) in asthma. METHODS: Thirty female Balb/c mice were randomly divided into 3 equal groups: control group; asthma group, sensitized on day 1, 8, and 15 and challenged from day 21 to 52 with periodically repeated intranasal drip of ovalbumin (OVA); and BUD treated group, undergoing intranasal drip of OVA as mentioned above and intranasal administration of BUD 2 hours before each OVA challenge. 24 h after the final OVA inhalation an invasive single-chamber whole body plethysmograph was used to assess the airway responsiveness. Then bronchoalveolar lavage fluid (BALF) was obtained and ELISA was used to measure the contents of interleukin (IL)-4 and IL-13. The mice were killed and their lungs taken out. HE staining and periodic acid Schiff (PAS) staining were used to observe the airway score of goblet cells. Peribronchiolar collagen deposition was imaged in Masson-stained lung sections. Biochemical assay was used to determine the total lung tissue level of collagen. Potass hydrolyse method was used to examine the content of hydroxyproline in the lung tissue. Western blotting was used to detect the protein expression of alpha-smooth muscle actin (SMA), JAK1, and STAT6. RT-PCR was used to detect the mRNA expression of alpha-SMA. RESULTS: The value of LogPC100 of the asthma group was 1.88 +/- 0.34, significantly higher than those of the BUD and control groups (1.79 +/- 0.18 and 0.82 +/- 0.78 respectively, both P = 0.000). The airway score of goblet cells of the asthma group was 3.05 +/- 0.23, significantly higher than those of the BUD and control groups (1.35 +/- 0.26 and 0.40 +/- 0.13 respectively, both P < 0.01). The hydroxyproline content of the asthma group was (459 +/- 47) microg/100 mg tissue, significantly higher than those of the BUD and control groups [(284 +/- 16) and (181 +/- 22) microg/100 mg tissue respectively, both P < 0.01]. The level of IL-4 of the asthma group was (14.4 +/- 1.12) ng/L, significantly higher than those of the BUD and control groups [(7.3 +/- 0.6) and (5.6 +/- 0.8) ng/L respectively, both P < 0.01]. The IL-13 level of the asthma group was (16.8 +/- 0.9) ng/L, significantly higher than those of the BUD and control groups [(10.6 +/- 0.9) and (5.6 +/- 0.8) ng/L respectively, both P < 0.01]. Treatment of BUD attenuated the allergen-induced airway hyperresponsiveness (AHR) and structural changes in airway, and decreased the values of the airway scores of goblet cells, and levels of hydroxyproline, IL-4, and IL-13 in comparison with the asthma group (all P < 0.01). Repeated OVA challenge resulted in an upregulation of the expression levels of alpha-SMA, JAK1 and STAT6 protein and alpha-SMA mRNA, while use of BUD suppressed these changes. The changes of JAK1 and STAT6 expression were correlated significantly with the changes in the airway score of goblet cells, hydroxyproline content, expression level of alpha-SMA, and levels of IL-4 and IL-13 in BALF (all P < 0.05). CONCLUSION: BUD ameliorates the progression of airway remodeling following prolonged allergen challenge via regulation of JAK1/STAT6 signal pathway.

Evaluation by indirect immunofluorescent assay and enzyme linked immunosorbent assay of the dynamic changes of serum antibody responses against severe acute respiratory syndrome coronavirus.

BACKGROUND: Severe acute respiratory syndrome coronavirus (SARS-CoV) is a newly emerging virus that gives rise to SARS patients with high rates of infectivity and fatality. To study the humoral immune responses to SARS-CoV, the authors evaluated IgG and IgM specific antibodies in patients' sera. METHODS: Two methods, enzyme-linked immunosorbent assay (ELISA) and indirect immunofluorescent assay (IFA), were used to detect specific serum IgG and IgM against SARS-CoV in 98 SARS patients and 250 controls consisting of patients with pneumonia, health-care professionals and healthy subjects. The serum antibody profiles were investigated at different times over one and a half years in 18 of the SARS patients. RESULTS: The sensitivity and specificity of ELISA for detecting IgG against SARS-CoV were 100.0% and 97.2% and for IgM 89.8% and 97.6% respectively; the figures using IFA for IgG were 100.0% and 100.0% and for IgM 81.8% and 100.0% respectively. During the first seven days of the antibodies trace test, no IgG and IgM were detected, but on day 15, IgG response increased dramatically, reaching a peak on day 60, remaining high up to day 180 and decreasing gradually until day 540. On day 15, IgM was detected, rapidly reached a peak, then declined gradually until day 180 when IgM was undetectable. CONCLUSION: The detection of antibodies against SARS virus is helpful in the clinical diagnosis of SARS.

Chemokine-like factor 1, a novel cytokine, contributes to airway damage, remodeling and pulmonary fibrosis.

BACKGROUND: Chemokine-like factor 1 (CKLF1) was recently identified as a novel cytokine. The full-length CKLF1 cDNA contains 530 bp encoding 99 amino acid residues with a CC motif similar to that of other CC family chemokines. Recombinant CKLF1 exhibits chemotactic activity on leucocytes and stimulates proliferation of murine skeletal muscle cells. We questioned whether CKLF1 could be involved in the pathogenesis of inflammation and proliferation in the lung. Therefore we used efficient in vivo gene delivery method to investigate the biological effect of CKLF1 in the murine lung. METHODS: CKLF1-expressing plasmid, pCDI-CKLF1, was constructed and injected into the skeletal muscles followed by electroporation. Lung tissues were obtained at the end of week 1, 2, 3 and 4 respectively after injection. The pathological changes in the lungs were observed by light microscope. RESULTS: A single intramuscular injection of CKLF1 plasmid DNA into BALB/c mice caused dramatic pathological changes in the lungs of treated mice. These changes included peribronchial leukocyte infiltration, epithelial shedding, collagen deposition, proliferation of bronchial smooth muscle cells and fibrosis of the lung. CONCLUSIONS: The sustained morphological abnormalities of the bronchial and bronchiolar wall, the acute pneumonitis and interstitial pulmonary fibrosis induced by CKLF1 were similar to phenomena observed in chronic persistent asthma, acute respiratory distress syndrome and severe acute respiratory syndrome. These data suggest that CKLF1 may play an important role in the pathogenesis of these important diseases and the study also implies that gene electro-transfer in vivo could serve as a valuable approach for evaluating the function of a novel gene in animals.

[Protective effect of specific antibody in serum of convalescent patient with SARS].

OBJECTIVE: To investigate inhibitory effect of serum severe acute respiratory syndrome (SARS) -specific antibodies from convalescent patients after half an year of onset on SARS-CoV-mediated cytopathic response. METHODS: SARS-CoV immunoglobulin G (IgG) antibody was determined by enzyme linked immunoadsorbent assay (ELISA). Twelve serum samples from convalescent patients, diluted by 1:8 with maintenance medium, were mixed with the three dilution supernatants of SARS-CoV. SARS-CoV were isolated, cultured and identified by the Guangzhou Institute of Respiratory Disease, and cultured with Vero E6 cell suspension. The extent of cytopathic response was observed. RESULTS: The absorbance (A) value of SARS-CoV IgG antibody ranged from 0.81 to 2.06 in patients after half an year of SARS onset, and form 0.79 to 2.01 in patients before half an year of SARS onset. The extent of cytopathic response was decreased by more than 25% in all 12 convalescent patients, as compared with control serum. CONCLUSION: The A value of SARS-CoV IgG antibody in serum of convalescent patients tended to elevate in half an year after SARS onset. SARS-CoV IgG antibody could inhibit SARS-CoV-mediated cytopathic response, indicating it might be one of protective antibodies.