CROSS-REACTIVE ANTIGENS BETWEEN A TICK, DERMACENTOR-VARIABILIS (ACARI, IXODIDAE), AND A MITE, PSOROPTES-CUNICULI (ACARI, PSOROPTIDAE)

The possibility of cross-reactive antigens between a mite (Psoroptes cuniculi) and a tick (Dermacentor variabilis) was examined. Sera from rabbits with long-term natural infestations and those with shorter experimental infestations of P. cuniculi were tested on both mite and tick tissues using the indirect immunofluorescence assay. Sera from BALB/c mice subjected to multiple tick (D. variabilis) infestations were also examined. Mite-infested rabbits had antibodies reactive with both mite and tick tissues, whereas mite-free rabbits did not. Reactive tick tissues included salivary glands and ovaries. Tick-infested mice had antibodies reactive only with tick tissues. It was concluded that immune reactions to mites in rabbits might possibly be falsely interpreted as immune reactions to ticks.