DEVELOPMENT OF AN IMMUNOMAGNETIC METHOD FOR SELECTIVE ISOLATION OF ACTINOBACILLUS-PLEUROPNEUMONIAE SEROTYPE-1 FROM TONSILS

An immunomagnetic separation technique (IMS) for the selective isolati on of Actinobacillus pleuropneumoniae serotype 1 was developed. Superp aramagnetic polystyrene beads (immunomagnetic beads [IMBs]) were coate d with purified rabbit immunoglobulin G specific for A. pleuropneumoni ae serotype 1. The antibody concentration, the number of IMBs, the inc ubation time, and the temperature of incubation influenced the recover y of the target bacteria. The sensitivity of the IMS technique was 1,0 00-fold higher than that of direct culture. When tonsils from animals from infected herds were tested, significantly more positive tonsils w ere detected by the IMS technique (68%) than by the standard procedure s (22%). The method represents an innovative and highly sensitive appr oach for the isolation of A. pleuropneumoniae from carrier animals.