Host-Parasite Interactions; Immune System; Lyme Disease; Borrelia burgdorferi
We are involved in research involving the host parasite relationship in Lyme Borreliosis. We have two ongoing projects. The first has to do with tick immunity, and to this end we are purifying ticks salivary and mid-gut antigens to determine the nature of the antigenic stimulation that leads to tick immunity and also preparing specific antibodies to screen expression libraries of such antigens. We have developed a system of measuring tick immunity in guinea pigs and apply and test our purified and recombinant antigens in this system.
Our second project involves the immune relationship between Borrelia burgdorferi and the host in chronic infection. We and others have shown that after several days of infection, the spirochetes, Borrelia burgdorferi, are not sensitive to antibodies which would protect a naive animal if they were on board prior to the inoculation of the infecting organisms. We have learned that the organism changes in vitro in response to a non-immune host stimulus. We are currently investigating what is the stimulus or stimuli and how does the organism change? What antigens does it stop producing on its surface and what new antigens are produced in vivo and are these protective in ways different than antigens found in broth grown organisms. Finally, while cell mediated immunity has not been found to be important in the protection of naive hosts from infection with Borrelia burgdorferi, it may well be that cell mediated immunity is effective in clearing the chronically infected host of tissue bound B. burgdorferi. This too is the subject of ongoing investigation.
Specialized Terms: Host parasite relationship in Lyme Borreliosis; immune relationship between Borrelia burgdorferi and the host in chronic infection
- Pedra JH, Narasimhan S, Deponte K, Marcantonio N, Kantor FS, Fikrig E. Disruption of the salivary protein 14 in Ixodes scapularis nymphs and impact on pathogen acquisition. Am J Trop Med Hyg. 2006 Oct;75(4):677-82.
- Neelakanta G, Li X, Pal U, Liu X, Beck DS, DePonte K, Fish D, Kantor FS, Fikrig E. Outer surface protein B is critical for Borrelia burgdorferi adherence and survival within Ixodes ticks. PLoS Pathog. 2007 Mar;3(3):e33.
- Li X, Neelakanta G, Liu X, Beck DS, Kantor FS, Fish D, Anderson JF, Fikrig E. Role of outer surface protein D in the Borrelia burgdorferi life cycle. Infection & Immunity 75(9):4237-4244, 2007.
- Narasimhan S, Sukumaran B, Bozdogan U, Thomas V, Liang X, DePonte K, Marcantonio N, Koski RA, Anderson JF, Kantor F, Fikrig E. A tick antioxidant facilitates the Lyme disease agent's successful migration from the mammalian host to the arthropod vector. Cell Host Microbe. 2007 Jul 12;2(1):7-18.
- Narasimhan S, DePonte K, Marcantonio N, Liang X, Royce TE, Nelson KF, Booth CJ, Koski B, Anderson JF, Kantor FS, Fikrig E. Immunity against Ixodes scapularis salivary proteins expressed within 24 hours of attachment thwarts tick feeding and impairs Borrelia transmission. Plos ONE. 2(5):e451.doi:10.1371/ journal.pone.0000451, 2007.
- Anaplasma phagocytophilum induces actin phosphorylation to selectively regulate gene transcription in Ixodes scapularis ticks. Sultana H, Neelakanta G, Kantor FS, Malawista SE, Fish D, Montgomery RR, Fikrig E. J Exp Med. 2010 Aug 2;207(8):1727-43. doi: 10.1084/jem.20100276. Epub 2010 Jul 26.