Spore surface display is one of attractive microorganism surface display systems. With the advantage of resistance attribute and specific assembly pattern, the technology of spore surface display now is attracting more and more attention. According to the current reports and main achievements of spore surface display, the structure and assembly of spores, the principle for construction and some existing spore surface display systems were elaborated in this paper. Now with the unique property of spores, the technique is not only widely used in production of vaccines but also has great applied potential in the field of biocatalysis and cell-factory.
Bacillus subtilis ; genetics ; metabolism ; Biocatalysis ; Biotechnology ; methods ; Gene Expression Regulation, Bacterial ; Genetic Engineering ; methods ; Recombinant Proteins ; genetics ; metabolism ; Spores, Bacterial ; genetics ; metabolism ; Tetanus Toxoid ; genetics ; immunology

Clostridium (C.) difficile is a common cause of nosocomial diarrhea in horses. Vancomycin and metronidazole have been used as standard treatments but are only moderately effective, which highlights the need for a novel alternative therapy. In the current study, we prepared antiserum of equine origin against both C. difficile toxins A and B as well as whole-cell bacteria. The toxin-neutralizing activities of the antibodies were evaluated in vitro and the prophylactic effects of in vivo passive immunotherapy were demonstrated using a conventional mouse model. The data demonstrated that immunized horses generated antibodies against both toxins A and B that possessed toxin-neutralizing activity. Additionally, mice treated with the antiserum lost less weight without any sign of illness and regained weight back to a normal range more rapidly compared to the control group when challenged orally with 10(7) C. difficile spores 1 day after serum injection. These results indicate that intravenous delivery of hyperimmune serum can protect animals from C. difficile challenge in a dose-dependent manner. Hence, immunotherapy may be a promising prophylactic strategy for preventing C. difficile infection in horses.
Animals ; Antibodies, Bacterial/blood/*immunology/therapeutic use ; Bacterial Proteins/immunology/therapeutic use ; Bacterial Toxins/immunology/therapeutic use ; Clostridium Infections/microbiology/prevention & control/*veterinary ; Clostridium difficile/*immunology ; Enterotoxins/immunology/therapeutic use ; Female ; Horse Diseases/microbiology/*prevention & control ; Horses ; Immune Sera/*immunology ; Immunization, Passive/*veterinary ; Mice ; Mice, Inbred C57BL ; Spores, Bacterial/immunology