CCL2 and Sepsis: Along with these changes, the mRNA levels of inflammatory mediators such as tumor necrosis factor-α (Tnf-α), chemokine ligand 2 (Ccl2), interleukin-6 (Il-6), interleukin-1β (Il-1β), and nitric oxide synthase 2 (Nos2) also demonstrated a marked elevation in the sepsis group (Fig. 1, C and D).