Failure of a heterologous recombinant Sca5/OmpB protein-based vaccine to elicit effective protective immunity against Rickettsia rickettsii infections in C3H/HeN mice

Authors

Sean P. Riley, University of Chicago, Department of Microbiology, Chicago, IL 60637, USA Howard T. Ricketts Laboratory, Argonne, IL 60439, USA Vector-Borne Disease Laboratories, Department of Pathobiological Sciences, Louisiana State University School of Veterinary Medicine, Baton Rouge, LA 70803, USA.
Marissa M. Cardwell, University of Chicago, Department of Microbiology, Chicago, IL 60637, USA Howard T. Ricketts Laboratory, Argonne, IL 60439, USA.
Yvonne G. Chan, University of Chicago, Department of Microbiology, Chicago, IL 60637, USA Howard T. Ricketts Laboratory, Argonne, IL 60439, USA.
Ludovic Pruneau, Vector-Borne Disease Laboratories, Department of Pathobiological Sciences, Louisiana State University School of Veterinary Medicine, Baton Rouge, LA 70803, USA.
Fabio Del Piero, Vector-Borne Disease Laboratories, Department of Pathobiological Sciences, Louisiana State University School of Veterinary Medicine, Baton Rouge, LA 70803, USA.
Juan J. Martinez, University of Chicago, Department of Microbiology, Chicago, IL 60637, USA Howard T. Ricketts Laboratory, Argonne, IL 60439, USA Vector-Borne Disease Laboratories, Department of Pathobiological Sciences, Louisiana State University School of Veterinary Medicine, Baton Rouge, LA 70803, USA jmartinez@lsu.edu.

Document Type

Article

Publication Date

12-1-2015

Abstract

Spotted fever group (SFG) rickettsial species are obligate intracellular tick-borne pathogens that are responsible for important human diseases. Previous reports have demonstrated the feasibility of using recombinant surface cell antigen Sca5/OmpB to elicit protective immunity against homologous challenges using murine models of Mediterranean spotted fever and Rocky Mountain spotted fever. In addition, the feasibility of generating cross-protective immunity against related rickettsial species has also been established, but the molecular basis for these phenomena was not explored. Here, we demonstrate that vaccination of C3H/HeN mice with a recombinant OmpB domain derived from Rickettsia conorii induced high titer humoral immune responses that are capable of recognizing the native OmpB protein at the R. rickettsii outer membrane, but this immunization was not sufficient to induce effective protective immunity. In contrast, animals vaccinated with a corresponding OmpB domain derived from R. rickettsii protected animals from fatal outcomes. These results demonstrate that vaccination with nearly identical antigens may not be an effective strategy to induce wide-ranging protective immunity against related SFG Rickettsia species.

Publication Source (Journal or Book title)

Pathogens and disease

First Page

ftv101

Recommended Citation

Riley, S. P., Cardwell, M. M., Chan, Y. G., Pruneau, L., Del Piero, F., & Martinez, J. J. (2015). Failure of a heterologous recombinant Sca5/OmpB protein-based vaccine to elicit effective protective immunity against Rickettsia rickettsii infections in C3H/HeN mice. Pathogens and disease, 73 (9), ftv101. https://doi.org/10.1093/femspd/ftv101