Isolation and immunological characterisation of allergens from salivary glands of the Australian paralysis tick Ixodes holocyclus.

Radioimmunoassay and Western blot analysis showed that salivary gland extract (SGE) prepared from Ixodes holocyclus was a more concentrated source of allergens than whole body extract. Isolation and partial immunological characterisation of allergens was performed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) of SGE, electroelution and Western blotting. Immunoblotting using allergic sera showed that partially purified SGE from I. holocyclus contained two common allergens of approximately 28 and 35 kilodaltons and several minor allergens. The two most common allergens gave radioimmunoassay ratios significantly greater than the less common allergens. The immunological purity of electroeluted allergens was confirmed by further SDS-PAGE, silver staining and Western blotting.