WESTERN-BLOT-ANALYSIS OF TICK ANTIGENS FROM A RHIPICEPHALUS-SANGUINEUS UNFED LARVAL EXTRACT AND IDENTIFICATION OF ANTIGENIC SITES IN TICK SECTIONS USING IMMUNOHISTOCHEMISTRY - A COMPARATIVE-STUDY BETWEEN RESISTANT AND SUSCEPTIBLE HOST SPECIES

Most parasite-host relationships are characterized by the development of resistance by the host, thus limiting the number of parasites. Howe ver, some cases are very unusual. In the relationship of the domestic dog with the brown dog-tick Rhipicephalus sanguineus this does not occ ur, whereas guinea pigs develop efficient resistance. Sera from domest ic dogs, crab-eating foxes and guinea pigs collected before and after infestation with R. sanguineus ticks, and after immunization with a wh ole tick adult or larval homogenate, were used in Western blot analysi s to compare and identify potential important antigens from a tick lar val homogenate. The same sera were tested in an indirect immunohistoch emistry assay in an attempt to compare relevant antigenic sites on his tological tick sections. The immunoblotting displayed antigens recogni zed only by the guinea pigs, as well as several shared antigens betwee n host species, depending on the kind of immunization. Immunohistochem istry revealed probable antigenic sites on the cells and tissues of ti cks, which varied depending on the kind of immunization (infestation o r vaccination) and the animal species involved.