Geometric mean fluorescence intensities of macrophages, without and without CCD, after incubation with GFP-labelled M. hyopneumoniae and E. coli. The green fluorescence intensity of PAMs following incubation with GFP-labelled M. hyopneumoniae (M. hyopneumoniae (pMHGFP-P97)) or GFP-labelled E. coli (E. coli (pKENmut2)) was measured and normalised against uninoculated PAMs. Error bars show standard error of the mean from two separate experiments, 6 replicates in total. Significant mean differences were determined by independent T-test (PAMs ± CCD and E. coli) and Mann–Whitney U test (PAMs ± CCD and M. hyopneumoniae), ***p < 0.001. Porcine alveolar macrophages (PAMs), cytochalasin D (CCD).