Fig. 6
NK cells promoted macrophage M1 polarization through secreting exosomes. 1 × 107 NK cells or 30 μg NK cell-derived exosomes were injected into the NK cell-depleted mice infected with PA in lung. Subsequently, a and b the percentage of M1- and M2-polarized macrophage in lung tissues was measured by flow cytometry, and then analyzed. c The expression of iNOS and Arg-1 in lung tissues was ensured by qRT-PCR. d ELISA assay was carried out to determine the production of cytokines in lung tissues. **P < 0.01 compared with NK (-) group