Consistent with these results in biochemical experiments and animal models, two prospective clinical trials in healthy donors and in chronic hepatitis C patients revealed that DPP4 inhibitor (sitagliptin) treatment resulted in a significant decrease in the truncated CXCL10 (3–77) concentration and a reciprocal increase in CXCL10 (1–77), with only minimal effects on the total levels of the chemokine [47]. Here, DPP4 is linked to chronic hepatitis C virus infection.