Dermonecrotic toxin (DNT) is identified as one of the most important virulence factor of Bordetella bronchiseptica. The complete coding sequence (4 356 bp) of the dnt gene was cloned into the prokaryotic expression vector pET-28a, and expressed in the Eschierichia coli BL21 (DE3) under IPTG (Isopropyl-beta-D-thiogalactopyranoside) induction. The recombinant His6-DNT protein showed immunological reactivity in the Western-blot analysis. The recombinant protein was purified from crude lysates of BL21 harboring pET-DNT with the purity of 93.2%. His6-DNT showed the dermonecrotic effects in the infant mouse assay. However, rabbit anti-serum against recombinant DNT protein could neutralize the dermonecrotic effects of native DNT to the infant mice in vivo. These findings suggest that the recombinant DNT protein retained the characteristics and immunogenicity of native DNT. Furthermore, this approach could be used to induce active immunity and serum immunoglobulin for production of a passive therapeutic reagent. In this study, we have shown that the recombinant His6-DNT protein retained the characteristics of native DNT of B. bronchiseptica, which built a good foundation for the further research on the structure and function of DNT.
Animals ; Animals, Newborn ; Bordetella bronchiseptica ; metabolism ; Escherichia coli ; genetics ; metabolism ; Genetic Vectors ; genetics ; Mice ; Neutralization Tests ; Recombinant Fusion Proteins ; biosynthesis ; genetics ; immunology ; Transglutaminases ; biosynthesis ; genetics ; Virulence Factors, Bordetella ; biosynthesis ; genetics

Bordetella (B) bronchiseptica is a common veterinary pathogen, but has rarely been implicated in human infections. Most patients with B. bronchiseptica infections are compromised clinically such as in patients with a malignancy, AIDS, malnutrition, or chronic renal failure. We experienced a case of relapsing peritonitis caused by B. bronchiseptica associated with continuous ambulatory peritoneal dialysis (CAPD). A 56-yr-old male, treated with CAPD due to end stage renal disease (ESRD), was admitted with complaints of abdominal pain and a turbid peritoneal dialysate. The culture of peritoneal dialysate identified B. bronchiseptica. The patient was treated with a combination of intraperitoneal antibiotics. There were two further episodes of relapsing peritonitis, although the organism was sensitive to the used antibiotics. Finally, the indwelling CAPD catheter was removed and the patient was started on hemodialysis. This is the first report of a B. bronchiseptica human infection in the Korean literature.
Anti-Bacterial Agents/pharmacology/therapeutic use ; Bordetella Infections/*diagnosis/microbiology ; Bordetella bronchiseptica/*metabolism ; Fibrosis ; Humans ; Kidney Failure/microbiology ; Male ; Middle Aged ; Peritoneal Dialysis, Continuous Ambulatory/*methods ; Peritoneum/pathology ; Peritonitis/*microbiology ; Recurrence

Fucoidan is a sulfated polysaccharide derived from brown seaweed, including Fucus vesiculosus. This compound is known to have immunostimulatory effects on various types of immune cells including macrophages and dendritic cells. A recent study described the application of fucoidan as a vaccine adjuvant. Vaccination is regarded as the most efficient prophylactic method for preventing harmful or epidemic diseases. To increase vaccine efficacy, effective adjuvants are needed. In the present study, we determined whether fucoidan can function as an adjuvant using vaccine antigens. Flow cytometric analysis revealed that fucoidan increases the expression of the activation markers major histocompatibility complex class II, cluster of differentiation (CD)25, and CD69 in spleen cells. In combination with Bordetella bronchiseptica antigen, fucoidan increased the viability and tumor necrosis factor-alpha production of spleen cells. Furthermore, fucoidan increased the in vivo production of antigen-specific antibodies in mice inoculated with Mycoplasma hyopneumoniae antigen. Overall, this study has provided valuable information about the use of fucoidan as a vaccine adjuvant.
Adjuvants, Immunologic/pharmacology ; Animals ; Antigens, Bacterial/*immunology ; Bacterial Vaccines/administration & dosage/*immunology ; Biomarkers/metabolism ; Bordetella bronchiseptica/*immunology ; Cells, Cultured ; Cytokines/*metabolism ; Female ; Flow Cytometry ; Fucus/*chemistry ; Gene Expression Regulation/drug effects ; Mice ; Mice, Inbred BALB C ; Mycoplasma hyopneumoniae/*immunology ; Polysaccharides/*pharmacology ; Spleen/metabolism