Immunomodulatory Effect after Irreversible Electroporation in Patients with Locally Advanced Pancreatic Cancer

He, Chaobin; Wang, Jun; Sun, Shuxin; Zhang, Yu; Li, Shengping

. . Modulation of Circulating Immune Cells. To investigate how IRE influences circulating immune cells, these cells were phenotypically characterized by evaluating the absolute number of helper T cell (CD4 + T cell, identified as CD3 + CD4 + ), cytotoxic T cell (CD8 + T cell, identified as CD3 + CD8 + ), regulatory T cell (Treg, identified as CD4 + CD25 + FoxP3 + ), and natural killer cell (NK cell, identified as CD3 − CD16 + CD56 + ) before (preOP) and after IRE treatment (D3 and D7). It was shown that the absolute numbers of CD4 + T cell (p<0.05), CD8 + T cell (p<0.05), and NK cell (p<0.01) were decreased immediately after IRE (D3), followed by a steady increase in the next few days (D7) (p<0.001). However, the trend for Treg cell reversed between preOP and D7 (p<0.05). The NK cell showed the most dramatic inverse effect for each time interval. Huge alterations of CD4 + T cell and CD8 + T cell were observed while there was a significant decrease in the ratio of CD4 + T cell to CD8 + T cell from D3 to D7 (p<0.05) ( Figure 1 ).