Objective To explore the changes in inflammatory reactions in tail-suspension mice infected by Klebsiella pneumoniae from spaceflight.Methods Tail suspension was used to simulate the physiological effects of microgravity.C57BL/6 mice were randomly divided into control (Con),control+K.pneumoniae T16-169 (Con+T16-169),tail suspension (TS) and tail suspension+K.pneumoniae T16-169 (TS+T16-169) groups.The level of inflammatory cytokines TNF-α,IL-6 and IL-1β mRNA in lung tissue and the plasma cytokine concentration were detected by RT-qPCR and xMAP technology,and HE staining was used to represent the morphological changes in lung tissue.Results Compared with the control group,the expression of inflammatory cytokines in lung tissue and plasma concentrations of all experimental groups were increased,and the difference in TS+T16-169 group was the most significant (P<0.01 or P<0.001).HE staining showed that the lung tissues in Con+T16-169 and TS+T16-169 groups were damaged in different degrees,and the damage of TS+T16-169 group was the most serious.Conclusion The K.pneumoniae from spaceflight significantly increases the expression of inflammatory cytokines in lung tissue and plasma concentrations after infecting tail-suspension mice,and induces more serious damages to the lung tissue,which suggests that inflammatory reactions can be increased in tail suspension mice infected by K.pneumoniae from spaceflight.

OBJECTIVESTo assess the efficacy of plasmid DNA encoding pac gene of Streptococcus mutans (S. mutans) intranasally immunized in gnotobiotic rats and to compare the effect of two different delivery systems.

METHODSSprague Dawley rats, infected with S. mutans at 20 days of age, were intranasally immunized with plasmid pCIA-P (group A), Dosper-DNA complex (group B), Bupivacaine-DNA complex (group C). Control rats were either immunized with plasmid pCI (group D), distilled water (group E) or immunized intramuscularly (group F). All the rats were boosted 2 weeks later. ELISA determined the antibodies against the vaccines. Keyes caries score was used to evaluate the anti- caries effectiveness of the vaccines at the terminal study.

RESULTSAs for the antibody reactions, there were significantly (P < 0.01) differences between rats immunized with DNA vaccine and non-immunized rats. And rats in group B and C had the significantly (P < 0.01) higher level of specific salivary anti-PAc IgA antibodies and rats (group B, C, F) had the significantly (P < 0.01) higher specific serum anti-PAc IgG responses to DNA vaccine. Keyes scores of rats (group B and C) were significantly (P < 0.01) lower than others.

CONCLUSIONSIntranasal immunization with plasmid pCIA-P encoding pac gene successfully reduces the caries and appears to be a promising approach against dental caries. Cationic liposome Dosper and local anesthetic bupivacaine could enhance the efficacy of DNA vaccine.

Administration, Intranasal ; Animals ; Antibodies, Bacterial ; blood ; Bacterial Proteins ; genetics ; Dental Caries ; prevention & control ; Female ; Immunization ; Immunoglobulin A ; blood ; Immunoglobulin G ; blood ; Membrane Glycoproteins ; Plasmids ; genetics ; Rats ; Rats, Sprague-Dawley ; Streptococcal Vaccines ; genetics ; immunology ; therapeutic use ; Streptococcus mutans ; genetics ; immunology ; Treatment Outcome ; Vaccines, DNA ; genetics ; immunology ; therapeutic use

OBJECTIVETo investigate the genotypic characterization of Porphyromonas gingivalis (Pg) and the heterogeneity of a potential virulence factor-PrtC.

METHODSArbitrarily primed polymerase chain reaction (AP-PCR) was applied to 80 Pg strains isolated from 24 unrelated Chinese periodontitis patients. PCR reaction was used to detect a fragment of the collagenase gene (PrtC gene). To evaluate the sequence heterogeneity of the Pg PrtC genes, sequence analysis of four PrtC gene of clinical isolates was performed.

RESULTSRandom primer OPA-05 and OPA-17 distinguished 7 AP-PCR profiles (I through VII). The majority of the strains belonged to type VII which accounted for 25.8%. A 548bp fragment of PrtC gene was detected from 24 clinical strains. The PCR products were verified by the restriction endonucleases PstI and PvuI. Sequence analysis showed 4 PrtC genes were heterogeneous in their nucleotide composition and differed from reference strain Pg 53977.

CONCLUSIONSThe results demonstrated genetic diversity existed among these clinical strains isolated from Chinese periodontitis patients and the PrtC genes are heterogeneous in their nucleotide sequence.

Adult ; Collagenases ; genetics ; DNA, Bacterial ; chemistry ; genetics ; Female ; Genetic Heterogeneity ; Humans ; Male ; Middle Aged ; Periodontitis ; microbiology ; Polymerase Chain Reaction ; methods ; Porphyromonas gingivalis ; genetics ; isolation & purification ; Sequence Analysis, DNA

OBJECTIVEProtein of Streptococcus mutans is considered as one of the virulence factors due to its ability to mediate the initial attachment of Streptococcus mutans to tooth surface. In this study, an anticaries DNA vaccine pCIA-P was used to immunize rats. The expression of PAc in different tissues in vivo, specific immune response and protection effects against dental caries were observed.

METHODSPlasmid pCIA-P was injected into rats by two different routs: intramuscular injection (i.m.) and targeted salivary gland immunization (TSG). Immunohistochemistry technique was used to detect the expression of PAc. Gnotobiotic rats were vaccinated with pCIA-P by three different approaches: TSG, intramuscular injection and buccal mucosal injection (i.o.). The specific immune responses were evaluated by ELISA and their anticaries effects were evaluated by Keyes caries scores.

RESULTSPAc was expressed in the sarcoplasm and sarcolemma of muscle fibers and submandibular glands, especially strongly positive in duct regions. The levels of serum specific anti-PAc IgG and salivary specific anti-PAc IgA in TSG immunization and buccal mucosal immunization group were significantly higher than those of other groups. The Keyes caries scores of those two groups were significantly lower than those of other groups.

CONCLUSIONThe plasmid pCIA-P could provoke specific immune responses as a novel immunogen. Mucosal immunization with pCIA-P appears to be an effective genetic immunization method against dental caries.

Animals ; Antibodies, Bacterial ; blood ; Bacterial Proteins ; genetics ; immunology ; Dental Caries ; prevention & control ; Germ-Free Life ; Immunization ; Male ; Membrane Glycoproteins ; Rats ; Rats, Wistar ; Streptococcal Vaccines ; immunology ; Streptococcus mutans ; immunology ; Vaccines, DNA ; immunology

OBJECTIVETo construct a fusion anti-caries DNA vaccine pGLUA-P carrying GLU fragment from gtfB gene of Streptococcus mutans GS-5 and A-P fragment including the A region and P region of PAc protein from a DNA anti-caries vaccine pCIA-P, and to investigate its expression in prokaryotic and eukaryotic cells.

METHODSThe sequence of GLU fragment in pGLU plasmid was testified by DNA sequencing. The fusion anti-caries DNA vaccine was constructed by ligating A-P fragment from pCIA-P to pGLU. The expression of GLUA-P fusion protein in E. coli BL21 (DE3) was induced by IPTG and checked by SDS-PAGE electrophoresis. pGLUA-P was transfected in vitro to cultured rat primary muscle cells by cation liposome Dosper, and immunohistochemical method was used to test the expression of GLUA-P fusion protein in cells.

RESULTSGLU sequence was identical with relative sequence of GTF-I (GS-5 strain) in Gene Bank. Recombinant eukaryotic expression plasmid pGLUA-P was confirmed to have both GLU and A-P fragment. After pGLUA-P was transferred into E. coli (DE3), it could express a new 115 000 protein by the induce of IPTG. Specific brown products could be found in the cytoplasm of cultured rat primary muscle cells transfected by pGLUA-P.

CONCLUSIONSFusion anti-caries DNA vaccine pGLUA-P is successfully constructed and confirmed by sequencing and enzymes digestion. Fusion GLUA-P protein can be correctly expressed in prokaryotic and eukaryotic cells.

Animals ; Animals, Newborn ; Bacterial Proteins ; genetics ; metabolism ; Cells, Cultured ; Cloning, Molecular ; Dental Caries ; prevention & control ; Electrophoresis, Polyacrylamide Gel ; Escherichia coli ; genetics ; Gene Expression ; Glucosyltransferases ; genetics ; metabolism ; Membrane Glycoproteins ; Muscle, Skeletal ; cytology ; metabolism ; Plasmids ; genetics ; Rats ; Rats, Wistar ; Recombinant Fusion Proteins ; genetics ; metabolism ; Streptococcal Vaccines ; genetics ; immunology ; therapeutic use ; Streptococcus mutans ; genetics ; immunology ; Transfection ; Vaccines, DNA ; genetics ; therapeutic use