Immunology of interactions between ticks and hosts.
Infestation with ixodid tick stimulates the immune regulatory and effector pathways of the hosts involving antigen presenting cells, T-lymphocytes, B-lymphocytes, basophils, mast cells, eosinophils and a variety of bioactive molecules like cytokines, antibodies and complement. Tick-mediated immunosuppression has been investigated using cells derived from infested animals and by exposing cells from uninfected animals to tick salivary gland molecules. Tick-induced suppression of host immune defences is characterized by reduced ability of lymphocytes from infested animals to proliferate in vitro in the presence of concanavalin A (Con A), diminished primary antibody responses to T-cell dependent antigen, and decreased elaboration of macrophage (IL-1 and TNF-alpha) and Th1-lymphocyte cytokines (IFN-gamma), whereas Th2 cytokines production (IL-4, IL-5 and IL-10) is enhanced. It is known that IL-10 inhibits Th1 cell development and also reduces the in vitro T-lymphocyte proliferative response to Con A stimulation. Proteins which inhibited T-lymphocyte in vitro responsiveness to Con A were also isolated from tick salivary glands.
Brossard
M
M
Institute of Zoology, University of Neuchâtel, Switzerland.
Wikel
S K
SK
D000818:Animals; D000917:Antibody Formation; D001402:B-Lymphocytes / Q000276:immunology; D006790:Host-Parasite Interactions / Q000276:immunology*; D007165:Immunosuppression Therapy; D007801:Langerhans Cells / Q000276:immunology; D008213:Lymphocyte Activation; D012469:Salivary Glands / Q000502:physiology; D012471:Salivary Proteins and Peptides / Q000276:immunology / Q000378:metabolism; D013601:T-Lymphocytes / Q000276:immunology; D013984:Tick Infestations / Q000276:immunology*; D013987:Ticks / Q000276:immunology*
D012471:Salivary Proteins and Peptides