Isolation and identification of excretory-secretory and somatic antigens from the Oestrus ovis larvae by SDS-PAGE and immunoblotting

Oestrus ovis is an economically important parasite of small ruminants and a zoonotic parasite with many reports of ophthalmomyiasis in human from Iran and other countries. The aim of the peresent studywas the isolation and identification of excretory-secretory (ES) and somatic (S) antigens of O. ovis second and third stage larvae (L۲, L۳) collected from Arabi sheep breeds located in southwest of Iran. Positive sera were prepared by marking the sheep, taking blood sample and direct observation of the parasite in the head. Somatic antigens of the larvae (SL۲, SL۳) were prepared by sonication. Larval excretory-secretory antigens (ESL۲, ESL۳) were prepared by incubation the larvae in RPMI-۱۶۴۰ RPMI medium. Electrophoretic protein profiles of ESL۲ two, ESL۳ seven, SL۲ eight,SL۳ fifteen bands (from ۷۹.۰ to below ۱۴.۴ KDa) were shown. In immunoblotting with positive sera, four common bands in SL۲ and SL۳ at ۵۸, ۴۲.۰, ۲۹.۰ and ۲۸.۰ kDa, one specific band in SL۳ at ۴۷.۰ kDa and one band in ESL۲, at ۲۸.۰ kDa, and three bands in ESL۳ at ۵۸.۰, ۴۲.۰, ۲۹.۰ and ۲۸.۰ kDa were recognized. Among the profiles, the ۲۸ kDa protein was the most common antigenic component. Nevertheless, the antigenic proteins ۲۹, ۵۸ kDa were a common protein in electrophoretic patterns of both S and ES proteins of L۲ and L۳ but, ۴۲.۰ kDa antigen the only one detected in immunoblot but not in S and ES protein profiles of the larvae. Therefore, the antigens ۲۹.۰, ۴۲.۰ and ۵۸.۰ kDa can be used for further studies of protective effects and serological diagnostic methods.

Keywords:

Immunoblotting , Oestrus ovis , Sheep