This Article Full Text Full Text (PDF) Other Versions of this Article: IAI.00982-06v1 74/11/6339    most recent Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Babcock, G. J. Articles by Thomas, W. D. Search for Related Content PubMed PubMed Citation Articles by Babcock, G. J. Articles by Thomas, W. D., Jr.

 Previous Article  |  Next Article 

Infection and Immunity, November 2006, p. 6339-6347, Vol. 74, No. 11
0019-9567/06/$08.00+0     doi:10.1128/IAI.00982-06
Copyright © 2006, American Society for Microbiology. All Rights Reserved.

Human Monoclonal Antibodies Directed against Toxins A and B Prevent Clostridium difficile-Induced Mortality in Hamsters

Gregory J. Babcock,^1, Teresa J. Broering,^1, Hector J. Hernandez,^1, Robert B. Mandell,¹ Katherine Donahue,¹ Naomi Boatright,¹ Anne M. Stack,³ Israel Lowy,² Robert Graziano,² Deborah Molrine,¹ Donna M. Ambrosino,¹ and William D. Thomas Jr.^1*

Massachusetts Biologic Laboratories, University of Massachusetts Medical School, Jamaica Plain, Massachusetts 02130,¹ Medarex, Inc., Bloomsbury, New Jersey 08804,² Children's Hospital Boston, Division of Emergency Medicine, Harvard Medical School, Boston, Massachusetts 02115³

Received 20 June 2006/ Returned for modification 10 August 2006/ Accepted 31 August 2006

Clostridium difficile is the leading cause of nosocomial antibiotic-associated diarrhea, and recent outbreaks of strains with increased virulence underscore the importance of identifying novel approaches to treat and prevent relapse of Clostridium difficile-associated diarrhea (CDAD). CDAD pathology is induced by two exotoxins, toxin A and toxin B, which have been shown to be cytotoxic and, in the case of toxin A, enterotoxic. In this report we describe fully human monoclonal antibodies (HuMAbs) that neutralize these toxins and prevent disease in hamsters. Transgenic mice carrying human immunoglobulin genes were used to isolate HuMAbs that neutralize the cytotoxic effects of either toxin A or toxin B in cell-based in vitro neutralization assays. Three anti-toxin A HuMAbs (3H2, CDA1, and 1B11) could all inhibit the enterotoxicity of toxin A in mouse intestinal loops and the in vivo toxicity in a systemic mouse model. Four anti-toxin B HuMAbs (MDX-1388, 103-174, 1G10, and 2A11) could neutralize cytotoxicity in vitro, although systemic toxicity in the mouse could not be neutralized. Anti-toxin A HuMAb CDA1 and anti-toxin B HuMAb MDX-1388 were tested in the well-established hamster model of C. difficile disease. CDA1 alone resulted in a statistically significant reduction of mortality in hamsters; however, the combination treatment offered enhanced protection. Compared to controls, combination therapy reduced mortality from 100% to 45% (P < 0.0001) in the primary disease hamster model and from 78% to 32% (P < 0.0001) in the less stringent relapse model.

Published ahead of print on 11 September 2006.

Editor: D. L. Burns

These authors contributed equally to this work.

This article has been cited by other articles:

• Monaghan, T, Boswell, T, Mahida, Y R (2008). Recent advances in Clostridium difficile-associated disease. Gut 57: 850-860 [Abstract] [Full Text]  
• Musher, D. M., Logan, N., Mehendiratta, V., Melgarejo, N. A., Garud, S., Hamill, R. J. (2007). Clostridium difficile colitis that fails conventional metronidazole therapy: response to nitazoxanide. J Antimicrob Chemother 59: 705-710 [Abstract] [Full Text]