PDCD1 and dysplasia: To further confirm the above-mentioned data indicating a shift from pro- to anti-inflammatory T cells in EAC, we analyzed the protein expression levels of CD4, FOXP3 and PD1 in paraffin-embedded specimens of healthy esophagus, Barrett’s esophagus, mucosa with low-grade and high-grade dysplasia and early stage (pT1) EACs (Fig. 5a).