Salivary Gland Changes and Host Antibody Responses Associated with Feeding of Male Lone Star Ticks (Acari: Ixodidae)

Abstract

The goal of this study was to demonstrate that male lone star ticks, Amblyomma americanum (L.), actively feed on rabbits during attachment and that the host is capable of mounting an immune response against male salivary gland proteins. During attachment, it was shown that male tick salivary glands hypertrophy. An enzyme-linked immunosorbant assay was used to detect rabbit serum proteins in the midgut of previously attached male ticks. SDS-polyacrylamide gel electrophoresis showed that the proteins expressed in the male tick salivary gland changed during feeding, with several new proteins in the 15- to 50-kDa range synthesized during attachment. Rabbits mounted a detectable antibody response against male tick salivary gland proteins after 2 sequential feedings of male ticks. The antibodies were directed against a spectrum of male salivary gland proteins ranging from 18 to 160 kDa. Several of these proteins were not recognized by antibodies directed against female tick saliva proteins, and thus may be specific male salivary gland components. This evidence indicates that male A. americanum ticks actively feed during attachment, that their salivary gland proteins change during feeding, and that male salivary gland proteins are immunogenic.