SUPPRESSIVE EFFECT OF BRONCHOALVEOLAR LAVAGE FLUID FROM PIGS INFECTEDWITH MYCOPLASMA-HYOPNEUMONIAE ON CHEMILUMINESCENCE OF PORCINE PERIPHERAL NEUTROPHILS

Bronchoalveolar lavage fluid (BALF) from pigs experimentally infected with Mycoplasma hyopneumoniae suppressed the chemiluminescence (CL) re sponse of porcine polymorphonuclear neutrophils (PMN). The suppressive effect was significantly correlated with the concentration of prostag landin E2 (PGE2) in the BALF, Furthermore, purified human PGE2 suppres sed the CL response of porcine PMN. The increased level of PGE2 follow ing infection with M, hyopneumoniae may be responsible for the suppres sion of PMN function in the airway of infected pigs. The decrease of P MN function may be responsible for exacerbation of mycoplasmal pneumon ia by secondary infection with pulmonary bacterial pathogens.