OBJECTIVE: To investigate the inhibitory effects of levofloxacin (LEV) combined with cellulase against bacille CalmetteGuerin (BCG) biofilms in vitro. METHODS: The mature growth cycle of BCG biofilms was determined using the XTT method and crystal violet staining. BCG planktonic bacteria and BCG biofilms were treated with different concentrations of LEV and cellulose alone or jointly, and the changes in biofilm biomass were quantified with crystal violet staining. The mature BCG biofilm was then treated with cellulase alone for 24 h, and after staining with SYTO 9 and Calcofluor White Stain, the number of viable bacteria and the change in cellulose content in the biofilm were observed with confocal laser scanning microscopy. The structural changes of the treated biofilm were observed under scanning electron microscopy. RESULTS: The MIC, MBC and MBEC values of LEV determined by broth microdilution method were 4 μg/mL, 8 μg/mL and 1024 μg/mL, respectively. The combined treatment with 1/4×MIC LEV and 2.56, 5.12 or 10.24 U/mL cellulase resulted in a significant reduction in biofilm biomass (P < 0.001). Cellulase treatments at the concentrations of 10.24, 5.12 and 2.56 U/mL all produced significant dispersion effects on mature BCG biofilms (P < 0.001). CONCLUSION LEV combined with cellulose can effectively eradicate BCG biofilm infections, suggesting the potential of glycoside hydrolase therapy for improving the efficacy of antibiotics against biofilmassociated infections caused by Mycobacterium tuberculosis.
Levofloxacin/pharmacology* ; Gentian Violet/pharmacology* ; BCG Vaccine/pharmacology* ; Anti-Bacterial Agents/pharmacology* ; Biofilms ; Cellulases/pharmacology* ; Microbial Sensitivity Tests

This study was purposed to investigate the effect of bacillus calmette-guerin (BCG) on the expansion of human dendritic cells (DC) from peripheral blood of pediatric patients with leukemia in vitro. The experiment was divi-ded into two groups: the control and the test group, and the latter group was divided into 3 subgroups: BCG (only BCG), GTI (GM-CSF, TNF-α, IL-4) and GTIB (GM-CSF, TNF-α, IL-4 plus BCG). On day 9 of culture the DCs were counted in each groups, the phenotypes of DC were determined by flow cytometry and these DC were stained with Wright-Giemsa for observation and photography under microscopy. The results showed that the test groups all obtained a certain amount of typical DC; the number of DC in the BCG subgroup is lower than that in the GTI and GTIB subgroups (t=4.20; 6.36, p<0.01); there was no significant difference between the GTI and the GTIB subgroups (t=2.25; p>0.05). The rate of CD1a+ in the BCG subgroup was obviously higher than that in the control group (t=3.04, p<0.05), but was lower than that in the GTI and the GTIB subgroups (t=2.79, 6.41, p<0.05), there was no significant difference between the GTI and the GTIB subgroups (t=0.65, p>0.05). The rate of HLA-DR+, CD83+ in the BCG group was higher than that in the control group (t=4.77, 4.15; p<0.05), but lower than that in the GTI and the GTIB subgroups (t=6.65, 3.19; p<0.05). The rate of HLA-DR+, CD83+ in the GTI subgroup was lower than that in the GTIB subgroup (t=5.64, 2.98; p<0.05). It is concluded that BCG not only promotes the proliferation of DC derived from human peripheral blood of leukemia patients in vitro, but also cooperates with rhGM-CSF, rhTNF-α and rhIL-4 in promoting the maturation of DCs.
BCG Vaccine ; immunology ; pharmacology ; Cell Differentiation ; drug effects ; Cells, Cultured ; Child ; Dendritic Cells ; cytology ; drug effects ; Humans ; Leukemia ; immunology ; Mycobacterium bovis ; immunology

OBJECTIVETo investigate the antitumor effect of recombinant IFN-alpha-2b-BCG on mouse bladder cancer MB49 cells in vitro, and to explore its antitumor mechanisms.

METHODSMB49 cells were co-cultured with recombinant BCG or wild BCG, and than were examined by light and transmission electron microscopy. The cell growth was assessed by MTT assay, and apoptosis rate and MHC-I of the MB49 cells was detected by flow cytometry using AO and Hoechst33258 fluorescence immunostaining.

RESULTSThe hIFN-alpha-2b-BCG-treated tumor cells showed slow growth, detachment of some cells, and various degree of degeneration. Light microscopy revealed organelle disorganization, chromatin aggregation, nuclear pyknosis, and cytolysis in some cells. Cellular membrane bulged and some bubbles were seen under fluorescence microscope using AO staining. Hoechst33258 assay also depicted frequent apoptosis in the tumor cells. The MTT assay showed that rBCG more actively than the wild BCG inhibited the proliferation of MB49 cells. The apoptosis rate of the recombinant BCG group was 19.7% and 46.6% at the time point of 24 h and 48 h, respectively, significantly higher than 10.8% and 20.9%, respectively, in the wild BCG group. The results of flow cytometry indicated that both types of BCG enhanced the expression of MHC-I in the MB49 cells, but more effective in the recombinant BCG group.

CONCLUSIONThe recombinant hIFN-alpha-2b-BCG has more strong immuno-modulatory properties, anti-tumor effect on MB49 cells and induces apparent cytotoxicity in the bladder cancer cells in vitro.

Adjuvants, Immunologic ; pharmacology ; Animals ; Antineoplastic Agents ; pharmacology ; Apoptosis ; drug effects ; BCG Vaccine ; pharmacology ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Cytotoxicity, Immunologic ; Histocompatibility Antigens Class I ; metabolism ; Interferon-alpha ; pharmacology ; Mice ; Recombinant Proteins ; pharmacology ; Urinary Bladder Neoplasms ; metabolism ; pathology

OBJECTIVETo study the expression of signal transducer and activator of transcription 5b (STAT5b) mRNA and interleukin-4 (IL-4) mRNA in blood mononuclearcells in a rat model of asthma and the effect of montelukast (MK) and BCG-polysaccharide and nucleic acid injection (BCG-PSN) on STAT5b mRNA and IL-4 mRNA expression.

METHODSFifty-two male Sprague-Dawley rats (weight:140-200 g) were randomly divided into four groups: asthma, MK treated and BCG-PSN-treated and control groups. Rat model of asthma was prepared by ovalbumin (OVA) sensitization. The rats were sacrificed 24 hrs after the last sensitization. Blood eosinophils (EOS) were counted. Plasma contens of IL-4 and interferon-gamma (IFN-gamma) were measured using ELISA. Expression of STAT5b mRNA and IL-4 mRNA in blood mononuclearcells was detected with SYBR GREEN I fluorescent quantitation PCR method.

RESULTSBlood contents of STAT5b mRNA and IL-4 mRNA in the untreated asthma group were significantly higher than those in the other three groups (<0.01). Blood EOS count and plasma IL-4 contents in the untreated asthma group significantly increased, while plasma IFN-gamma contents significantly decreased compared with the other three groups (<0.01). There were no significant differences in the parameters measured among the MK-treated, the BCG-PSNjtreated and the control groups. STAT5b mRNA expression was positively correlated to IL-4 mRNA expression, IL-4 content and EOS count (r=0.730,0.650, 0.664, respectively; <0.01), but negatively correlated to IFN-gamma content (r=-0.798; <0.01).

CONCLUSIONSSTAT5b mRNA and IL-4 mRNA were strongly expressed in blood mononuclearcells in rats with asthma, and there was a positive correlation between them. MK and BCG-PSN had inhibitory effects on the expression of STAT5b mRNA and IL-4 mRNA, which might be contributed to suppression of airway inflammation in asthma.

Acetates ; pharmacology ; Animals ; Asthma ; blood ; drug therapy ; pathology ; BCG Vaccine ; pharmacology ; Interferon-gamma ; biosynthesis ; Interleukin-4 ; genetics ; Leukocytes, Mononuclear ; metabolism ; Male ; Quinolines ; pharmacology ; RNA, Messenger ; blood ; Rats ; Rats, Sprague-Dawley ; STAT5 Transcription Factor ; genetics

OBJECTIVENeonatal Bacillus Calmette-Guerin (BCG) vaccination could decrease asthma prevalence in human according to "hygiene hypothesis". The authors proposed a hypothesis that effect of BCG vaccination on inhibiting asthma in human might be reversed by respiratory virus infection. The objective of this study was to observe combined effects of neonatal BCG vaccination and respiratory syncytial virus (RSV) infection on experimental asthma in mice.

METHODSNeonatal BALB/c mice were divided into five groups. Control and ovalbumin (OVA) groups were mock-vaccinated at birth and mock-infected at 3 weeks of age. BCG + OVA group was BCG-vaccinated and mock-infected. RSV + OVA group was mock-vaccinated and RSV-infected. BCG + RSV + OVA group was BCG-vaccinated and RSV-infected. Except for control group, all the other groups underwent ovalbumin (OVA) sensitization and challenge. Airway responsiveness to inhaled methacholine was measured and bronchoalveolar lavage (BAL) was performed after the last challege. Cells in BAL fluid (BALF) were counted. Cytokines in BALF and serum OVA-specific IgE were detected by ELISA and inflammatory characteristics of lungs was scored by staining with hematoxylin and eosin.

RESULTS(1) The numbers of total white cells, lymphocytes, monocytes, neutrophils, and eosinophils in the BALF from all OVA-sensitized/challenged groups were significantly greater than those in control (P < 0.01), and BCG + OVA group had significantly lower total white cells, lymphocytes and eosinophils as compared with other OVA-sensitized/challenged groups (P < 0.05 or 0.01). (2) All OVA-sensitized/challenged groups had significantly lower IFNgamma (P < 0.05) and higher IL-4 (P < 0.05) level in BALF as compared with control, but there was no significant difference among all OVA sensitized/challenged groups. There was no significant difference in IL-10 level between all experimental groups. (3) All OVA-sensitized/challenged groups showed significantly higher serum OVA-specific IgE titers than control (P < 0.05 or 0.01), but no significant difference was found among all OVA sensitized/challenged groups. (4) RSV + OVA and BCG + RSV + OVA groups displayed the highest airway resistance and subsequently in order as follows: OVA group, BCG + OVA group and control group in severity of airway hyperreactivity (AHR), but no significant difference was found between RSV + OVA and BCG + RSV + OVA groups. (5) Histological score of peribronchiolitis, perivasculitis, alveolitis, and peribronchial eosinophilia in all OVA-sensitized/challenged groups was significantly higher than that in control. BCG + OVA group had significantly milder peribronchiolitis and peribronchial eosinophilia than the other OVA-sensitized/challenged groups (P < 0.05) and significantly milder alveolitis than OVA and BCG + RSV + OVA groups (P < 0.05).

CONCLUSIONNeonatal BCG vaccination decreased asthmatic inflammation and AHR and RSV infection could reverse anti-asthma effect of neonatal BCG vaccination in OVA-sensitized/challenged mouse model.

Animals ; Animals, Newborn ; Asthma ; immunology ; prevention & control ; BCG Vaccine ; administration & dosage ; immunology ; pharmacology ; Bronchoalveolar Lavage Fluid ; Disease Models, Animal ; Enzyme-Linked Immunosorbent Assay ; Eosinophils ; drug effects ; immunology ; secretion ; Immunoglobulin E ; analysis ; immunology ; Interferon-gamma ; analysis ; immunology ; Interleukin-10 ; analysis ; immunology ; Interleukin-4 ; analysis ; immunology ; Leukocytes ; drug effects ; immunology ; secretion ; Lung ; drug effects ; immunology ; Mice ; Mice, Inbred BALB C ; Ovalbumin ; administration & dosage ; immunology ; toxicity ; Respiratory Syncytial Virus Infections ; immunology ; Respiratory Syncytial Viruses ; immunology ; pathogenicity ; Treatment Outcome

OBJECTIVETo investigate the effect of bacillus Calmette-Guerin (BCG) on Toll-like receptors (TLRs) expression and cytokine production in human bladder cancer cell line T24.

METHODSHuman transitional carcinoma cell line T24 was cultured in RPMI1640 medium with 10% FBS, BCG was added into the cell culture with various doses in bacteria-cell ratio. After T24 cells were stimulated by BCG for 1 hour, total RNA of cells was extracted. RT-PCR procedure was conducted with the primer of TLR-2 and TLR-4, and the products were analyzed with agarose gels electrophoresis. Then the expression of TLR-2 and TLR-4 in T24 cells was assessed by the analyzing system of gel imaging. After the stimulation culture for 12 hours, the supernatant of cells was collected. The levels of IL-4 and IL-12 in each sample were assayed by ELISA method.

RESULTSThe expression level of either TLR-2 or TLR-4 was increased by the stimulation of BCG in a dose-dependent manner, the effects reached the maximal level at the dose of BCG as 10 bacilli per cell. The production of IL-12 in T24 cells was also increased gradually by the stimulation of BCG in a dose-dependent manner, and the dose of BCG obtained maximal effect was 10 bacilli per cell, which is coincident with the results observed in the expression of TLRs. There was no difference showed on the production of IL-4 between T24 cells stimulated with BCG and control.

CONCLUSIONSThe stimulation of BCG not only up-regulated the expression of TLR-2 and TLR-4, but also increased the production of IL-12 in bladder cancer T24 cell line. The expression of TLRs and the production of cytokine in bladder cancer cells may be related to the BCG-induced immunol response to human bladder cancer.

BCG Vaccine ; pharmacology ; Cell Line, Tumor ; Dose-Response Relationship, Drug ; Electrophoresis, Agar Gel ; Enzyme-Linked Immunosorbent Assay ; Gene Expression Regulation, Neoplastic ; drug effects ; Humans ; Interleukin-2 ; analysis ; Interleukin-4 ; analysis ; Membrane Glycoproteins ; genetics ; Receptors, Cell Surface ; genetics ; Reverse Transcriptase Polymerase Chain Reaction ; Toll-Like Receptor 2 ; Toll-Like Receptor 4 ; Toll-Like Receptors ; Urinary Bladder Neoplasms ; genetics ; metabolism ; pathology