IFNy-induced expression of HLA-DP, DQ, DR in meningeal fibroblasts is completely blocked by TGFβ₁.

<p>A) In vehicle-treated leptomeningeal explant cultures only leptomeningeal/perivascular macrophages express HLA-DP, DQ, DR (indicated by arrows). B) IFNy increases intensity of HLA expression on macrophage cells and greatly induces HLA expression in meningeal fibroblasts. C) TGFβ₁ has no effect on basal leptomeningeal/perivascular macrophage or meningeal fibroblast HLA expression. D) However, TGFβ₁ completely inhibits IFNy-induced meningeal fibroblast HLA expression, without affecting leptomeningeal/perivascular macrophage HLA expression. DAB brightfield images have been inverted for image analysis. Scale bar = 100 µm. E) Quantification of HLA expression shows a massive increase in HLA expression in leptomeningeal explant cultures with IFNy but not with TGFβ₁ + IFNy (N = 12).