Main participants: Matt Padula and Kevin Broady

Progress to date: The Australian paralysis tick (Ixodes holocyclus) is endemic along the east coast of Australia and causes the death of thousands of companion animals and livestock each year. Death follows ascending paralysis of the hindlimbs and respiratory failure. A canine antiserum is used for treatment but is expensive; must be administered early and the quality control is controversial. Three low molecular weight neurotoxins have been identified and isolated in our laboratory. Partial amino acid sequence data has been used to design PCR primers which have been employed to isolated the gene for one of the toxins. Research is currently underway to sequence the genes for the other tick neurotoxins. Synthetic neurotoxins have been produced by recombinant DNA and solid phase peptide synthesis techniques and are being investigated for vaccine potential.