Inhibition of inducible nitric oxide synthase production from macrophages by the paracrine effect of orbital fat-derived stem cells. (A) Lipopolysaccharide (LPS) dose-dependently enhanced CD68 expression and triggered inducible nitric oxide synthase (iNOS) and tumor necrosis factor alpha (TNFα) production. (B) Condition medium of orbital fat-derived stem cells (OFSCs-CM) inhibited LPS-induced iNOS production at a ratio of OFSCs/macrophages (MØ) of 1 and higher. (C) Neither LPS nor OFSCs-CM altered CD206 expression on MØ. t test, *P < 0.05, n = 3. TGFβ, transforming growth factor beta.