CCL2 and peripheral nerve injury: Due to the secretion of cytokines and chemokines such as monocyte chemoattractant protein-1 (MCP-1), tumor necrosis factor alpha (TNF-α), interleukin (IL) 1 beta (IL-1β), interleukin 6 (IL-6), and leukemia inhibitory factor (LIF) by de-differentiated Schwann cells following peripheral nerve injury, monocytes are recruited from the blood compartment into the distal segment of damaged axons within 2–3 days post-injury [1–4].