HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Related articles in The JI Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by LaRocca, T. J. Articles by Benach, J. L. Search for Related Content PubMed PubMed Citation Articles by LaRocca, T. J. Articles by Benach, J. L. Pubmed/NCBI databases Protein Substance via MeSH

Bactericidal Action of a Complement-Independent Antibody against Relapsing Fever Borrelia Resides in Its Variable Region^1,2

Center for Infectious Diseases, Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, NY 11794

A single chain variable fragment (scFv) of CB515, a complement-independent bactericidal monoclonal IgM against a relapsing fever Borrelia, was constructed to investigate the region wherein the unique bactericidal function resides. Monomeric CB515 scFv (26 kDa) was capable of binding its Ag on whole organisms and by immunoblot. This binding was shown to be species and serotype-specific to the 19 kDa variable small protein, recognized by its parent monoclonal IgM. A dose-dependent bactericidal effect of the CB515 scFv was detected by direct enumeration of spirochetes. Spirochetes incubated with the CB515 scFv before inoculation into mice grew into escape mutants, whereas spirochetes incubated with an irrelevant scFv developed as the original infecting serotype. This bactericidal effect, as seen at the ultrastructural level, was due to disruption of the outer membrane and to severe membrane blebbing eventually progressing to lysis. These results indicate that the variable region of CB515 is responsible for this bactericidal activity and that the constant region of the Ab is dispensable.

The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked advertisement in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.

¹ This work was supported by Grant R37-AI-27044 from the National Institute of Health.

² We used the facilities of the Northeast Biodefense Center U54AI075158 for protein purification.

³ Address correspondence and reprint requests to Dr. Jorge L. Benach, Department of Molecular Genetics and Microbiology, Center for Infectious Diseases, 5120 Centers for Molecular Medicine, Stony Brook University, Stony Brook, New York 11794-5120. E-mail address: jbenach{at}notes.cc.sunysb.edu

⁴ Abbreviations used in this paper: Vmp, variable major proteins; scFv, single chain variable fragment; Vsp, variable small protein; BSK-H, Barbour-Stoenner-Kelly-H; WAM, Web Ab Modeling; TEM, transmission electron microscopy; OM, outer membrane; V_H, variable heavy; V_L, variable low; CDR, complementarity-determining regions.

Related articles in The JI:

IN THIS ISSUE

The JI 2008 180: 5759-5760. [Full Text]  

This article has been cited by other articles:

				T. J. LaRocca, D. J. Holthausen, C. Hsieh, C. Renken, C. A. Mannella, and J. L. Benach The bactericidal effect of a complement-independent antibody is osmolytic and specific to Borrelia PNAS, June 30, 2009; 106(26): 10752 - 10757. [Abstract] [Full Text] [PDF]

				S. Malkiel, C. J. Kuhlow, P. Mena, and J. L. Benach The Loss and Gain of Marginal Zone and Peritoneal B Cells Is Different in Response to Relapsing Fever and Lyme Disease Borrelia J. Immunol., January 1, 2009; 182(1): 498 - 506. [Abstract] [Full Text] [PDF]

				S. J. Forbes, M. Eschmann, and N. J. Mantis Inhibition of Salmonella enterica Serovar Typhimurium Motility and Entry into Epithelial Cells by a Protective Antilipopolysaccharide Monoclonal Immunoglobulin A Antibody Infect. Immun., September 1, 2008; 76(9): 4137 - 4144. [Abstract] [Full Text] [PDF]