Affiliation:
1. Sealy Center for Vaccine Development, Center for Biodefense and Emerging Infections, Department of Microbiology and Immunology
2. Department of Pathology, University of Texas Medical Branch, Galveston, Texas 77555-1070
3. Department of Pediatrics, University of Texas Medical Branch, Galveston, Texas 77555-1070
4. Avanir Pharmaceuticals, Inc., San Diego, California
Abstract
ABSTRACT
Prevention of inhalation anthrax requires early and extended antibiotic therapy, and therefore, alternative treatment strategies are needed. We investigated whether a human monoclonal antibody (AVP-21D9) to protective antigen (PA) would protect mice, guinea pigs, and rabbits against anthrax. Control animals challenged with
Bacillus anthracis
Ames spores by the intranasal route died within 3 to 7 days. AVP-21D9 alone provided minimal protection against anthrax in the murine model, but its efficacy was notably better in guinea pigs. When Swiss-Webster mice, challenged with five 50% lethal doses (LD
50
s) of anthrax spores, were given a single 16.7-mg/kg of body weight AVP-21D9 antibody dose combined with ciprofloxacin (30 mg/kg/day for 6 days) 24 h after challenge, 100% of the mice were protected for more than 30 days, while ciprofloxacin or AVP-21D9 alone showed minimal protection. Similarly, when AVP-21D9 antibody (10 to 50 mg/kg) was combined with a low, nonprotective dose of ciprofloxacin (3.7 mg/kg/day) and administered to guinea pigs for 6 days, synergistic protection against anthrax was observed. In contrast, a single dose of AVP-21D9 antibody (1, 5, 10, or 20 mg/kg) but not 0.2 mg/kg alone completely protected rabbits against challenge with 100 LD
50
s of
B. anthracis
Ames spores, and 100% of the rabbits survived rechallenge. Further, administration of AVP-21D9 (10 mg/kg) to rabbits at 0, 6, and 12 h after challenge with anthrax spores resulted in 100% survival; however, delay of antibody treatment by 24 and 48 h reduced survival to 80% and 60%, respectively. Serological analysis of sera from various surviving animals 30 days postprimary infection showed development of a species-specific PA enzyme-linked immunosorbent assay antibody titer that correlated with protection against reinfection. Taken together, the effectiveness of human anti-PA antibody alone or in combination with low ciprofloxacin levels may provide the basis for an improved strategy for prophylaxis or treatment following inhalation anthrax infection.
Publisher
American Society for Microbiology
Subject
Infectious Diseases,Immunology,Microbiology,Parasitology
Reference39 articles.
1. Agrawal, A., J. Lingappa, S. H. Leppla, S. Agrawal, A. Jabbar, C. Quinn, and B. Pulendran. 2003. Impairment of dendritic cells and adaptive immunity by anthrax lethal toxin. Nature424:329-334.
2. Postexposure Prophylaxis against Anthrax: Evaluation of Various Treatment Regimens in Intranasally Infected Guinea Pigs
3. Beebe L. M. Babin R. Barnwell J. Zhong and G. Choi. 2004. Post-exposure therapeutic potential of PA MAb in an inhalation model of anthrax in New Zealand White rabbits. Presented at the American Society for Microbiology Biodefense Meeting Baltimore Md.
4. Bonuccelli, G., F. Sotgia, P. G. Frank, T. M. Williams, C. J. de Almeida, H. B. Tanowitz, P. E. Scherer, K. A. Hotchkiss, B. I. Terman, B. Rollman, A. Alileche, J. Brojatsch, and M. P. Lisanti. 2005. ATR/TEM8 is highly expressed in epithelial cells lining Bacillus anthracis ' three sites of entry: implications for the pathogenesis of anthrax infection. Am. J. Physiol. Cell Physiol.288:C1402-C1410.
5. Global Effects of Virulence Gene Regulators in a
Bacillus anthracis
Strain with Both Virulence Plasmids
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