Protein- and DNA-based anthrax toxin vaccines confer protection in guinea pigs against inhalational challenge with Bacillus cereus G9241

You Can't B. cereus - A Review of Bacillus cereus Strains That Cause Anthrax-Like Disease

Emerging strains of Bacillus cereus, traditionally considered a self-limiting foodborne pathogen, have been associated with anthrax-like disease in mammals, including humans. The strains have emerged by divergent evolution and, as exchange of genetic material in the Bacillus genus occurs naturally, it is possible that further isolates will be identified in the future. The strains vary in their genotypes and phenotypes, combining traits of both B. cereus and B. anthracis species. Cases of anthrax-like disease associated with these strains result in similar symptoms and mortality rates as those caused by B. anthracis. The strains are susceptible to frontline antibiotics used in the treatment of anthrax and existing vaccines provide protection in animal models. The emergence of these strains has reignited the debate surrounding classification of the B. cereus sensu lato group and serves as a reminder that the field of medical microbiology is constantly changing and remains an important and ongoing area of research.

Antibody response to HER2 extracellular domain and subdomains in mouse following DNA immunization

Human epidermal growth factor receptor 2 (HER2) is overexpressed in 15-20 % of breast cancer patients and is an appropriate target for immunotherapy in these patients. Monoclonal antibodies (mAbs) specific to HER2 are currently applied to treat breast cancer patients with HER2 overexpression. Active immunization with HER2 DNA or protein has been considered as a suitable alternative. The aim of this study is to evaluate anti-HER2 antibody response in serum of mice immunized with DNA constructs containing full extracellular domain (fECD) or subdomains of human HER2. Four extracellular subdomains and also fECD of HER2 were cloned into pCMV6-Neo vector. Different groups of Balb/C mice were immunized with HER2 DNA constructs and boosted with HER2 recombinant protein. The anti-HER2 antibody was subsequently determined by ELISA, flow cytometry, and immunohistochemistry. Anti-HER2 antibody was detected only in serum of mice immunized with fECD DNA. None of HER2 extracellular subdomains induced appreciable levels of anti-HER2 antibody. However, boosting with fECD or extracellular subdomain III (DIII) recombinant protein resulted in enhanced anti-HER2 fECD as well as anti-HER2 subdomain antibody responses. In this regard, almost all (99 %) of HER2-overexpressing BT474 cells could be detected by serum antibody from mice immunized with HER2 subdomain DNA and boosted with recombinant HER2 protein by flow cytometry. Similarly, serum of mice immunized with DIII DNA construct and boosted with recombinant DIII protein could also recognize these cells, but to a lesser extent (50 %). Our findings suggest that combination of HER2 DNA and protein immunization could effectively induce anti-HER2 antibody response in Balb/C mice.