Table 2.

Regulation of the adaptive immune response by preconditioned human mesenchymal stem cells.

Preconditioning approach	The source of cells	Secreted factors or expressed genes	Immunomodulatory effects	Reference
Hypoxia	G-MSCs	↑ IL-10 and FasL	↓ PBMC proliferation and ↑ apoptosis of PBMC	[53]
Hypoxia	AT-MSCs	↑ IDO, PD-L1, and CXCL10	↓ PBMC, CD4+, and CD8+ T cell proliferation	[54, 57]
IFN-γ	BM-MSCs	↑ IDO	↓ T cell proliferation, degranulation, and Th1 cytokine (IFN-γ, TNF-α, and IL-2) production	[59]
IFN-γ	UC-MSCs	↑ IDO	↑ expansion of Tregs	[60]
IL1-β	UC-MSCs	↑ COX-2, IL-6, and IL-8	↑ Tregs and Th2 cell proliferation and ↓ numbers of Th1 and Th17 cells	[28]
IFN-γ and TNF-α	BM-MSCs	↑ IDO	↓ T cell proliferation	[63]
IFN-γ and TNF-α	Placenta-derived MSCs	↑ PD-L2	↑ differentiation of CD4+IL-10+ and CD8+IL19+ Treg subpopulations	[64]
IFN-γ or TNF-α	WJ-MSCs	↑ IDO, PGE-2, CIITA, and ↓ HGF	↓ lymphocyte proliferation in the MLR	[65]
IFN-γ or TNF-α	BM-MSCs	↑ IDO, PGE-2, and CIITA	↓ mitogen-induced proliferation of lymphocytes	[65]
IFN-γ, TNF-α, IL-1α, IL-1β, and TLR ligands	BM-MSCs	↑ galectin 9	↓ T cell proliferation	[67]
IL17A	BM-MSCs	↑ IDO	↓ T cell activation and proliferation and ↑ expansion of Tregs	[66]
Budesonide	BM-MSCs	↑ IDO	↓ T cell activation and proliferation	[69]