OBJEVTIVETo study the effect of spvB/spvC gene on Salmonella virulence and the Host immune.

METHODSSTM.211, STM.211-Delta;spvB, STM.211-Delta;spvC, STM.211-Delta;spvB.spvC and PBS were infected with 0.2 mL 10(5) CFU corresponding strain respectively by intraperitoneal. We observed the mental status, movement, diarrhea, weight, pelage changed hair of the infected mouse. Then the level of IL-10, IL-12, IFN-γ were detected by ELISA. Finally, we observe the pathological changes of liver and spleen with the general view and the microscope.

RESULTSInfection symptoms of STM.211, STM.211-Delta;spvB and STM.211-Delta;spvC were significantly worse than PBS group, but there was no significant difference between STM.211-spvB.spvC group and PBS group. The secretion of IFN-γ and IL-12 of STM.211, STM.211-Delta;spvB, STM.211-Delta;spvC group were significantly lower than those in the STM.211-Delta;spvB.spvC group (P<0.05), but IL-10 secretion was significantly higher than STM.211-Delta;spvB.spvC group (P<0.05). There were no statistical significance among the STM.211, STM.211-Delta;SpvB, STM.211-Delta;spvC groups (P>0.05).

CONCLUSIONSSalmonella virulence can be affected obviously by spvB combined with spvC gene, but not by spvB or spvC. spvB/spvC gene can inhibit the TH1 cytokines (IFN-γ and IL-12) secretion but promote the TH2 cytokines (IL-10) expression, leading immune response trend to TH2 shift. It shows that spvB/spvC gene can help the bacteria evade the host immune defenses, leading to aggravation of infection.

Animals ; Cytokines ; immunology ; Interleukin-12 ; Mice ; Salmonella ; genetics ; pathogenicity ; Salmonella Infections ; immunology ; Virulence ; Virulence Factors ; genetics

Salmonella enterica Gallinarum (SG) causes fowl typhoid (FT), a septicemic disease in avian species. We constructed deletion mutants lacking the stress sigma factor RpoS, the nitric oxide (NO)-detoxifying flavohemoglobin Hmp, and the SsrA/SsrB regulator to confirm the functions of these factors in SG. All gene products were fully functional in wild-type (WT) SG whereas mutants harboring single mutations or a combination of rpoS, hmp, and ssrAB mutations showed hypersusceptibility to H2O2, loss of NO metabolism, and absence of Salmonella pathogenicity island (SPI)-2 expression, respectively. A triple-deletion mutant, SGDelta3 (SGDeltarpoSDeltahmpDeltassrAB), was evaluated for attenuated virulence and protection efficacy in two-week-old Lohmann layer chickens. The SGDelta3 mutant did not cause any mortality after inoculation with either 1 x 10(6) or 1 x 10(8) colony-forming units (CFUs) of bacteria. Significantly lower numbers of salmonellae were recovered from the liver and spleen of chickens inoculated with the SGDelta3 mutant compared to chickens inoculated with WT SG. Vaccination with the SGDelta3 mutant conferred complete protection against challenge with virulent SG on the chickens comparable to the group vaccinated with a conventional vaccine strain, SG9R. Overall, these results indicate that SGDelta3 could be a promising candidate for a live Salmonella vaccine against FT.
Administration, Oral ; Animals ; Bacterial Proteins/*genetics/immunology ; *Chickens ; Female ; Poultry Diseases/*immunology/microbiology ; Salmonella Infections, Animal/*immunology/microbiology ; Salmonella Vaccines/administration & dosage/genetics/*immunology ; Salmonella enterica/immunology/*physiology ; Vaccines, Attenuated/administration & dosage/genetics/immunology ; Virulence

To date, efforts to treat autoimmune diseases have primarily focused on the disease symptoms rather than on the cause of the disease. In large part, this is attributed to not knowing the responsible auto-antigens (auto-Ags) for driving the self-reactivity coupled with the poor success of treating autoimmune diseases using oral tolerance methods. Nonetheless, if tolerogenic approaches or methods that stimulate regulatory T (Treg) cells can be devised, these could subdue autoimmune diseases. To forward such efforts, our approach with colonization factor antigen I (CFA/I) fimbriae is to establish bystander immunity to ultimately drive the development of auto-Ag-specific Treg cells. Using an attenuated Salmonella vaccine expressing CFA/I fimbriae, fimbriae-specific Treg cells were induced without compromising the vaccine's capacity to protect against travelers' diarrhea or salmonellosis. By adapting the vaccine's anti-inflammatory properties, it was found that it could also dampen experimental inflammatory diseases resembling multiple sclerosis (MS) and rheumatoid arthritis. Because of this bystander effect, disease-specific Treg cells are eventually induced to resolve disease. Interestingly, this same vaccine could elicit the required Treg cell subset for each disease. For MS-like disease, conventional CD25+ Treg cells are stimulated, but for arthritis CD39+ Treg cells are induced instead. This review article will examine the potential of treating autoimmune diseases without having previous knowledge of the auto-Ag using an innocuous antigen to stimulate Treg cells via the production of transforming growth factor-beta and interleukin-10.
Animals ; Antigens, Bacterial/*immunology ; Arthritis, Rheumatoid/immunology/prevention & control ; Autoantigens/*immunology ; Fimbriae Proteins/*immunology ; Humans ; Multiple Sclerosis/immunology/prevention & control ; Salmonella/*immunology ; T-Lymphocytes, Regulatory/*immunology ; *Vaccination

OBJECTIVETo determine the distribution and sequence conservation of pagC gene in Salmonella paratyphi A isolates, and the immunogenicity and immunoprotection of its recombinant expression products (rPagC).

METHODSThe distribution of pagC gene in Salmonella paratyphi A isolates and its sequence conservation were examined by PCR and sequencing. A prokaryotic expression system of pagC gene was constructed and the expressed rPagC was extracted by Ni-NTA affinity chromatography. SDS-PAGE and Bio-Rad Gel Image Analyzer were applied to examine the expression and yield of rPagC. The antigenicity and immunoreactivity of rPagC were detected by immunodiffusion test, ELISA and Western Blot assay. The immunoprotective effect of rPagC against infection of Salmonella paratyphi A in mice was determined, while the agglutinative effect of sera from rPagC-immunized mice was measured by micro-Widal's test.

RESULTSAll the Salmonella paratyphi A isolates tested had the pagC gene, the similarity of nucleotide and amino acid sequences was 99.1 %-100 % and 98.4 %-100 %, respectively. The constructed prokaryotic expression system expressed rPagC with high efficiency. The rPagC immunized rabbit produced a high level antibody and it also combined with antiserum against whole cell of S. paratyphi A to generate a positive Western hybridization signal. ELISA results indicated that 97.1 % (66/68) paratyphoid patients infected with Salmonella paratyphi A were positive for rPagC antibody in their serum specimens. When mice were immunized with 100 μg or 200 μg rPagC, the immunoprotective rates were 73.3 % (11/15) or 86.7 % (13/15), respectively. The sera from rPagC-immunized mice offered 1:10-1:40 agglutination titers with the H antigens of Salmonella paratyphi A and Salmonella typhi.

CONCLUSIONPagC gene has an extensive distribution in Salmonella paratyphi A isolates. rPagC can be used as the candidate antigen in genetic engineering vaccine due to its fine immunogenicity and powerful immunoprotective effect.

Agglutination Tests ; Animals ; Antibodies, Bacterial ; blood ; Antigens, Bacterial ; genetics ; immunology ; Bacterial Proteins ; genetics ; immunology ; Bacterial Vaccines ; Membrane Proteins ; genetics ; immunology ; Mice ; Rabbits ; Recombinant Proteins ; genetics ; immunology ; Salmonella paratyphi A ; genetics ; immunology ; Sequence Homology, Amino Acid ; Sequence Homology, Nucleic Acid

OBJECTIVETo study the effection of suppression murine melanoma growth by Intratumor injection of recombinant attenuated salmonella carrying heat shock protein 70 and herpes simplex virus thymidine kinase genes.

METHODSPlasmids PCMV-mtHSP70-IRES-TK were electro-transferred into salmonella typhimurium SL7207 to construct recombinant salmonella typhimurium. In vivo, Recombinant bacteria were injected into the mouse melanoma and the antitumor effection was observed. The survival period was recorded and safety analysis for this vaccine in each group.

RESULTSIn vivo, the mtHSP70/HSV-tk recombinant bacteria can suppress tumor growth significantly and extend survival. After recombinant Salmonella, 10(9) CFU/mL, was administered as an intratumoral injection, No diarrhea were observed. During therapy, body weight did not change markedly.

CONCLUSIONResults of the animal experiment suggests intratumor injection of recombinant attenuated salmonella typhimurium containing mtHSP70 and HSV-tk genes, has targeting ability against B16 tumor cell and could significantly inhibit tumor growth .

Animals ; Bacterial Proteins ; genetics ; immunology ; Cancer Vaccines ; genetics ; immunology ; pharmacology ; Genetic Therapy ; methods ; HSP70 Heat-Shock Proteins ; genetics ; immunology ; Melanoma, Experimental ; microbiology ; pathology ; therapy ; Mice ; Mice, Inbred C57BL ; Mycobacterium tuberculosis ; genetics ; Salmonella typhimurium ; genetics ; immunology ; Simplexvirus ; enzymology ; genetics ; Skin Neoplasms ; therapy ; Thymidine Kinase ; genetics ; immunology ; Vaccines, Attenuated ; genetics ; immunology ; pharmacology ; Vaccines, DNA ; genetics ; immunology ; pharmacology

Salmonella choleraesuis C500 strain is an attenuated vaccine preventing piglet from paratyphoid and can also be used as a live vector of other DNA vaccines. Through mucosal immunization, immune response to specific antigens carried by it can be induced. To enhance the immune efficiency of DNA vaccine it carried, promoter Ptrc was inserted into the down stream of the human cytomegalovirus (CMV) immediate early promoter of eukaryotic expression plasmid pEGFP-C1. Then transcription terminator rrnbT1T2 was inserted into down stream of the multiple clone sites of pEGFP-C1, and the dual-promoter expression vector pEGFPPtrcR was constructed. Using 1xTSS method, we transformed the recombinant plasmid into C500, and obtained C500/pEGFPPtrcR. We used SDS-PAGE and Western blotting to detect the expression of report gene EGFP. Strong green fluorescence was observed under fluorescent microscope. The stable passages of this recombinant bacterium were at least 20 generations in vitro. Using liposome we transfected plasmid pEGFPPtrcR into Vero cell. After 24 h, green fluorescent was observed, showing the expression of EGFP in nuclei and endochylema. The construction of dual-promoter expression vector pEGFPPtrcR was successful. The foreign gene was expressed in Salmonella strain C500 and somatocytes, resulting in increased antigen expression. This research provides a foundation for the research of new DNA vaccines which use Salmonella C500 as carrier.
Animals ; Genetic Vectors ; genetics ; Green Fluorescent Proteins ; genetics ; metabolism ; Plasmids ; genetics ; Promoter Regions, Genetic ; genetics ; Recombinant Proteins ; genetics ; metabolism ; Salmonella Vaccines ; genetics ; immunology ; Salmonella arizonae ; genetics ; immunology ; metabolism ; Swine ; Vaccines, DNA ; genetics

Salmonella enterica serovar Choleraesuis strain C500 is a live, attenuated vaccine that has been used in China for over 40 years to prevent piglet paratyphoid. The objective of this study was to evaluate the potential of attenuated Salmonella enterica serovar Choleraesuis C500 strain with a delta asd mutant as an effective live vaccine vector by the Asd+ balanced-lethal host-vector system. Here, we compared the characteristics of S. enterica serovar Choleraesuis delta asdC500 strain with the parent C500 strain, including phenotype, growth rate, virulence, safety, and expression for heterologous antigen. The mean generation times of delta asdC500 mutant, the vector control delta asdC500 (pYA3493), and the parent avirulent C500 vaccine strain in Luria broth were 30.7, 28.1, and 27.9 min, respectively. The fermentation patterns of theses three strains on different carbohydrates, and the levels of production of H2S, were similar. The O and H antigens of delta asdC500 mutant, delta asdC500 (pYA3493) and delta asdC500 (pYA-F1P2) were 6,7:C:1,5, identical to the parent strain C500. By the method of Reed and Muench, groups of mice were challenged by the intraperitoneal route with different amounts of delta asdC500 (pYA3493) or the parent C500 strain, and the virulence of delta asdC500 (pYA3493) with LD50 of 1.1 x 10(7) CFU was a little lower than C500 with LD50 of 4.4 x 10(6) CFU. All piglets inoculated with delta asdC500 (pYA3493) or C500 survived, and no signs of disease were observed during the entire experimental period. No major differences were found in these two groups. In addition, the recombinant pYA-F1P2 plasmid was very stable in the recombinant delta asdC500 (pYA-F1P2) strain, which expressed secretorily a large amount of the recombinant filamentous hemagglutinin type I domain and pertactin region 2 domain antigen (rF1P2) of Bordetella bronchiseptica. In this study, we have shown that the delta asdC500 mutant had a series of biological characteristics similar to the parent vaccine strain C500. Furthermore, the strain could express secretorily a large amount of heterologous antigen. It is likely that this Salmonella expression and delivery system could be easily adapted to develop multivalent recombinant Salmonella vaccines against infectious agents using the Asd+ balanced-lethal host-vector system.
Amino Acid Oxidoreductases ; genetics ; Animals ; Bacterial Proteins ; genetics ; Gene Deletion ; Genetic Vectors ; Mice ; Mutation ; Salmonella Vaccines ; genetics ; immunology ; Salmonella enterica ; genetics ; immunology ; pathogenicity ; Swine ; Transduction, Genetic ; Vaccines, Attenuated ; genetics ; immunology ; Vaccines, Synthetic ; genetics ; immunology ; Virulence

The fusion protein (F) gene of Newcastle disease virus was amplified by polymerase chain reaction (PCR) from the recombinant plasmid pVAX1-F, and subcloned into eukaryotic expression vector pmcDNA3. 1+. The F gene was identified by sequencing. The recombinant plasmid was transformed into attenuated Salmonella typhimurium SL7207, and the recombinant was designated as SL7207 (pmcDNA3. 1-F). In vitro and in vivo experiments showed that the plasmid stability of pmcDNA3. 1-F was apparently higher than that of pcDNA3. 1-F in SL7207. In order to compare the immune response induced by these two re combinant bacteria, BALB/c mice were immunized orally with them at the dosage of 2 x 10(9) CFU respectively. Both SL7207(pcDNA3. 1-F) and SL7207(pmcDNA3. 1-F) initiated F-specific serum and mucosal antibodies in immunized mice. Furthermore, 4-day-old SPF chickens were immunized with SL7207(pcDNA3. 1-F) and SL7207(pmcDNA3. 1-F) at the dosage of 5 x 10(9) CFU and boosted two weeks later with the same dosage. Humoral and intestinal mucosal immune responses were observed and their levels were significantly higher than that of negative and positive controls. The result of protective efficacy showed that the chickens immunized with SL7207(pmcDNA3. 1-F) had the protective rate of 70.0%, higher than that of the SL7207 (pcDNA3. 1-F) with 50.0%. In summary, the DNA vaccine delivered by attenuated Salmonella typhimurium has good immunogenicity. A novel mucosal DNA vaccine has been developed and could be useful for controlling the infection and epidemic of Newcastle disease in the poultry.
Animals ; Chickens ; Female ; Immunization ; Mice ; Mice, Inbred BALB C ; Newcastle disease virus ; immunology ; Plasmids ; Salmonella typhimurium ; genetics ; Vaccines, Attenuated ; immunology ; Vaccines, DNA ; immunology ; Viral Vaccines ; immunology

In the current work, the fusion gene including somatostatin (SS) and the hepatitis B surface antigen gene was cloned into a balanced lethal system plasmid (pYA3493), and then transformed into asd- attenuated Salmonella choleraesuis C500 strain, the positive transformant without antibiotic resistance gene was confirmed by restriction analysis and DNA sequencing, designated as pYA-SS. The expression and immunogenicity of fusion protein were detected by SDS-PAGE and Western blot analysis. These results show that the recombinant prokaryotic expression plasmid pYA-SS could express the SS fusion protein with good immunogenicity in C500 strain. In above all, this study could provide reliable materials to develop novel, good and safe vaccine in enhancing the growth of animals.
Animals ; Artificial Gene Fusion ; Cloning, Molecular ; Hepatitis B Surface Antigens ; genetics ; Humans ; Plasmids ; genetics ; Prokaryotic Cells ; metabolism ; Recombinant Fusion Proteins ; biosynthesis ; genetics ; immunology ; Salmonella arizonae ; genetics ; metabolism ; Somatostatin ; biosynthesis ; genetics ; immunology

INTRODUCTIONNeuropsychiatric manifestations can occur in up to two-thirds of patients with systemic lupus erythematosus (SLE). The presentations as well as the underlying immunopathogenic mechanisms can be heterogeneous and therefore have an enormous impact on therapeutic options.

CLINICAL PICTUREWe describe 2 patients who presented similarly with acute onset binocular reversible visual loss. The first patient had anti-phospholipid syndrome and optic neuritis, while the second patient suffered from posterior reversible leukoencephalopathy syndrome.

TREATMENTPatient one was treated with anti-coagulation and immunosuppression while the second patient required the withdrawal of immunosuppression and supportive therapy.

OUTCOMEBoth patients responded favourably and had complete visual recovery.

CONCLUSIONSDifferent management strategies have to be employed for similar presentations having different aetiologies, underscoring the need for constant clinical vigilance.

Adult ; Antiphospholipid Syndrome ; complications ; etiology ; Brain Diseases ; etiology ; immunology ; Epilepsy, Tonic-Clonic ; etiology ; Female ; Humans ; Lupus Erythematosus, Systemic ; complications ; microbiology ; physiopathology ; therapy ; Lupus Vasculitis, Central Nervous System ; diagnosis ; Magnetic Resonance Imaging ; Optic Neuritis ; etiology ; Salmonella Infections ; complications ; Salmonella enteritidis ; Time Factors ; Vision Disorders ; etiology ; immunology