Detection and quantification of Ornithodoros-specific anti-tick antibody by competitive inhibition ELISA.

The objective of this study was to develop a highly specific enzyme-linked immunosorbent assay (ELISA) for the serological detection of anti-Ornithodoros tick antibodies in animals. Affinity-purified rabbit anti-Ornithodoros IgG antibodies were employed in indirect competitive inhibition ELISA assays designed to measure the anti-Ornithodoros antibody titers in other animal species using the domestic goat (Capra hircus) as a large animal model. Repeated infestation of goats with Ornithodoros coriaceus was found to elicit the formation of antibodies capable of inhibiting the binding of the Ornithodoros-specific rabbit IgG. Western blot analysis of goat and rabbit anti-tick antisera demonstrated both animal species to respond immunologically to a set of 9 major protein bands in O. coriaceus salivary gland extracts. The results of these experiments demonstrate that a history of animal exposure to O. coriaceus may be detected serologically by competitive inhibition ELISA.