Table 3.

Paracrine effectors of MSCs in the regulation of T cells and NK cells.

Factors	Effectiveness	Mechanisms	Reference
PD-L1	Inhibit T cells proliferation	Interact with PD-1 on T cells	[66]
FASL	Induce T cells apoptosis	Interact with FAS on T cells	[67]
Galectin-1	Downregulate inflammation	Inhibit cytotoxicity of T cells and restore the proliferation of CD4+ and CD8+ T cells.	[68]
TGF-β1	Inhibit T cells activation	Activate TGF-β signal pathway and arrest T cells in G0 phase	[69, 70]
S1P in MSCs-Exo	Regulate the balance of Tregs and Th17 cells	Regulate expression of Foxp3 in CD4+ T cells	[73]
IL-10	Promote the expansion of Treg cells	Induce KYN expression	[38]
LIF	Induce Th17 cells differentiation	Activate ERKs signal and deactivate STAT3 signal	[39]