Master of Science (MS)


Veterinary Medical Sciences - Pathobiological Sciences

Document Type



Several members of the spotted fever group (SFG) of Rickettsia are transmitted to the host through infected ixodid (hard) ticks, which can serve as both vectors and reservoirs. Multiple studies have demonstrated that ticks secrete proteins into the bite site of the host that suppress innate and adaptive immune responses. While this suppression of immune responses is beneficial to the tick, it may also be beneficial to the transmitted Rickettsia. We hypothesize that Rickettsia utilize the tick’s ability to alter the host immune response at the tick feeding site to successfully establish infection. In the current study, we analyzed how the tick transmission influenced the response to Rickettsia infection by comparing the innate immune response following intradermal versus tick-inoculation of R. amblyommii in the skin. In particular, we analyzed mRNA expression of Toll-like receptor (TLR) and TLR adaptor/effector genes as well as proinflammatory cytokines and chemokines. Data was analyzed using One-way ANOVA and Newman-Keuls post tests. The results of this study are the first to delineate the immunomodulatory milieu associated with rickettsial infection during the natural route of tick exposure.



Document Availability at the Time of Submission

Release the entire work immediately for access worldwide.

Committee Chair

Kevin R. Macaluso