Isolation and characterization of salivary antigens from Hyalomma anatolicum anatolicum.

This study demonstrates the involvement of a large number of salivary proteins in the acquisition of resistance to Hyalomma anatolicum anatolicum. Using immunoblotting, sera from hypersensitized rabbits were shown to react with nine proteins in the saliva and 17 in salivary gland extracts (SGE) from 96 h fed female ticks. The salivary antigens had molecular weights in the range of 14 400 to 130 000. All the antigens identified in the saliva and 12 of the SGE antigens were glycoprotein in nature and a majority of them appeared to be common to different stages of feeding. In addition antigen I (molecular weight 130 000) showed acid phosphatase and antigen III (molecular weight 96 000) showed both non-specific esterase and aminopeptidase activity. Three high molecular weight proteins isolated from saliva (antigen I, antigen II--molecular weight 103 000 and antigen III), gave immediate hypersensitivity reactions in intradermal inoculation into rabbits which had previously been exposed to ticks. Antigens II and III also elicited a strong delayed hypersensitivity reaction. These results may help to explain the nature of the immune mechanisms which effect resistance against H. a. anatolicum.