Figure 4.

PLA2G4D protein expression in exosomes of the LAD mast cell–like line. (A) K562-CD1a cells were pulsed with PLA2G4D (1 µg/ml), LAD2 lysate (10 µg/ml protein content), LAD2 culture medium control (1 ml per 10⁶ cells), LAD2 supernatant (1 ml per 10⁶ cells), or LAD2 exosome (10 µg/ml protein content). Then, the cells were incubated with T cells from patients with psoriasis (n = 3) and controls (n = 3). IFN-γ production was measured by ELISPOT. Data are mean ± SEM and were analyzed using two-way ANOVA. (B) Cytosolic PLA₂ activity was measured in exosome fraction, culture supernatant, and culture medium of the LAD2 mast cell–like line using biochemical activity assay. Results represent one sample and are a typical representation of at least three individual experiments. Data are mean ± SEM and were analyzed using two-way ANOVA. (A and B) *, P < 0.05; **, P < 0.01; ***, P < 0.001; ****, P < 0.0001. (C) Protein expression of PLAG4D by LAD2 exosomes was detected using Western blotting, and intensity was evaluated by ImageJ and compared with CD63, a known exosomal marker. Results represent one sample and are a typical representation of at least three individual experiments. Data are mean ± SEM.