Table 1.

Overview of peripheral immune cell contribution to pain development and recovery.

Immune cell	Role	Mediators (Therapeutic target)
CD4+ Th1 cells	Promote pain development and maintenance	IL17A, leukocyte elastase
CD4+ Th2 cells	Promote pain recovery	IL-10, IL-4
CD8+ T cells (educated)	Promote pain recovery	IL-10
Tregs	Promote pain recovery	IL-10, IL-35, TGF-β, TNFR2
Inflammatory macrophages	Promote pain development and maintenance	CX3CL1, ROS
Anti-inflammatory macrophages	Alleviate pain	Endogenous opioids, TGF-β, IL-10