IDENTIFICATION OF ANTICOAGULANT ACTIVITIES IN THE SALIVARY-GLANDS OF THE SOFT TICK, ORNITHODOROS-SAVIGNYI

Salivary gland extracts of the sand tampan, Ornithodoros savignyi, pro longed the activated partial thromboplastin time (APTT) and prothrombi n time (PT) significantly in a concentration-dependent manner. There w as also a pronounced inhibition of human activated factor Xa (fXa) by salivary gland extracts. The salivary gland extracts inhibited chromog enic assays specific for both fXa and thrombin. Sodium dodecyl sulphat e-polyacrylamide gel electrophoresis (SDS-PAGE) of the salivary gland proteins followed by elution of specific areas or bands from a polyvin ylidene difluoride (PVDF)-membrane, showed that various anticoagulant factors are present when screened by means of the APTT assay. The most active component was associated with a band of M(r) of 14 kDa. Partia l purification of this component was achieved using isoelectric focusi ng (IEF) and size-exclusion high-performance liquid chromatography (HP LC).