Preparation and Purification of Polyclonal Antibodies against Mycobacterium Avium Paratuberculosis Antigens in Rabbit

Johne’s disease is the chronic granulomatous enteritis of ruminants، and a major health hazard worldwide. In recent years، researchers have focused on mycobacterium avium subsp. paratuberculosis (MAP) antigens in diagnostic tests. Identification of antibodies against MAP antigens is، therefore، effective for the diagnosis or preparation of vaccine. The aim of this study was to prepare and purify polyclonal antibodies against MAP antigens. A New Zealand white rabbit was immunized at a certain time period with MAP antigens and Freund’s adjuvant. After the immunization of the animal، the rabbit was bled to obtain enriched serum. Immunoglobulins were obtained via sedimentation with ammonium sulfate 35% and then IgG was purified by ion exchange (DEAE-cellulose) chromatography. Serologic test was used to evaluate the interaction of antigens and antibodies. Ion exchange chromatography of IgG showed one peak، and SDS_PAGE of IgG showed a single band. Serologic test was applied and clear precipitation lines were appeared up to 1:16 dilution، which indicated the high quality of the product. In this study، the humoral immune response was induced well by immunization with MAP antigens in a New Zealand white rabbit and polyclonal antibodies were produced in high titers. Polyclonal antibodies are relatively inexpensive and easy to produce in large quantities and can connect to the more connective sites، resulting in better sensitivity. Identification of polyclonal antibodies via immunological tests can play a significant role in studying MAP disorders.