FIG 1.

Immunosuppressive effects of PGE₂. (a to d) PBMCs from uninfected cattle (n = 6 [a to c] or 8 [d]) were cultured with PGE₂ in the presence of anti-CD3 and anti-CD28 MAbs for 72 h. The proliferation of CD4⁺ cells (a) and CD8⁺ cells (b) was assayed by flow cytometry. IFN-γ (c) and TNF-α (d) production was determined by ELISA. (e to k) PBMCs from uninfected cattle (n = 6 [e to i] or 7 [j and k]) were cultured with PGE₂ for 24 h. Real-time PCR was performed in duplicate to quantitate the mRNA expression of IFN-γ (e), IL-2 (f), TNF-α (g), IL-10 (h), STAT3 (i), and PD-L1 (j). The expression of PD-L1 protein was measured by flow cytometry (k). Statistical significance was determined by the Steel-Dwass test (a to c) or the Wilcoxon signed-rank test (d to k).