IL10 and oral lichen planus: As a cytokine secreted by macrophages, monocytes, and T lymphocytes, IL10 is thought to be involved in the pathogenesis of OLP.[9,31] IL10 exhibits diverse functions in different T lymphocytes (such as T helper cell (Th) 1, Th2, and cluster of differentiation 4+ T lymphocytes), and high levels of serum and saliva IL10 were also found in the OLP patients.