Distribution of LAP + CD 4 + T cells in pancreatic cancer

Objective: The purpose of this study was to investigate the role of LAP+CD4+ T cell in pancreatic cancer immunity. Methods: LAP and CD4 double staining was performed for tumor tissues and peri-tumor tissues from 35 patients with pancreatic cancer, and normal pancreatic tissues from 35 patients with benign lesions. Average number of the LAP+CD4+ T cell in each visual field was quantified. Results: The number of LAP+CD4+ T cell/high-magnification microscope field (400×) in the pancreatic cancer tissues was 8.38±1.44, which was significantly higher than that (5.21±1.24) in the peri-pancreatic cancer tissues and that (1.49±0.64) in the normal pancreatic tissues with benign lesions. Furthermore, in the pancreatic cancer tissues, LAP+CD4+ T cells were present as clusters in the tumor stroma and closely associated with CD4+ T lymphocytes. In contrast, in the peri-pancreatic cancer tissues and normal pancreatic tissues, LAP+CD4+ T cells were distributed sparsely. Conclusions: LAP+CD4+ T cells was increased in pancreatic cancer tissues and may inhibit local anti-tumor immunity.