Mesenchymal stem cell-derived microRNAs: Key immunomodulators to prevent ocular tissue degeneration

Table 2 Effects of mesenchymal stem cell-derived microRNAs in dry eye disease

Type of MSC	MiRNA	Target	Expression pattern	Function	Ref.
Human umbilical cord-MSC	MiR-204	IL-6R	Upregulated	Downregulated IL-6/IL-6R/STAT3 signaling responsible for macrophage phenotypes and alleviated dry eye (prospective clinical trial)	Zhou et al[63]
Human umbilical cord-MSC	MiR-100-5p	mTOR	Upregulated	Attenuated by skewed macrophages into a M2 phenotype and increased Treg proportion	Li et al[66]
Human umbilical cord-MSC	MiR-125b, let-7b, miR-6873	IRAK1	Upregulated	Inhibited ocular surface inflammation by multitargeting the IRAK1/TAB2/NF-κB signaling pathway	Wang et al[65]
Rat bone marrow-MSC	MiR-21-5p	TLR4	Upregulated	Decreased production of inflammatory and promoted synthesis of immunosuppressive cytokines and enhanced Tregs-driven suppression of inflammatory Th17 cells	Zhao et al[67]
Mouse adipose-derived MSC	MiR-223-3p	Fbxw7	Upregulated	Alleviated ocular surface damage and decreased pro-inflammatory cytokines or chemokines by targeting Fbxw7	Wang et al[68]

Fbxw7: F-box and WD repeat domain containing 7; IL: Interleukin; IL-6R: Interleukin 6 receptor; IRAK1: Interleukin 1 receptor-associated kinase 1; miRNA: MicroRNA; MSC: Mesenchymal stem cell; mTOR: Mechanistic target of rapamycin; NF-κB: Nuclear factor kappa B; STAT3: Signal transducer and activator of transcription 3; TAB2: TGF-beta activated kinase 1; Th17: T helper type 17; TLR4: Toll-like receptor 4; Treg: Regulatory T cell.