Table 4.
Mechanism of action with MSCs and EVs on NK cell.
| Cell type | Immune cell | Mechanism | Effect | Reference |
|---|---|---|---|---|
| MSC | NK cell | regulating indoleamine-2, 3-dioxygenase (IDO) and prostaglandin E2 (PGE2) | inhibit the activity of NK cells | (103, 104) |
| BM-MSCs | NK cell | inhibit IL-12 and IL-21 | Suppression NK cell proliferation but increase IFN-γ and IFN-α production | (105, 106) |
| TLR4+MSC | NK cell | – | inhibitory effect on NK cells and the receptor NKG2D | (107) |
| FL-MSC-EXO | NK cell | regulating TGF-β | inhibit the proliferation, activation and cytotoxicity of NK cells | (108) |
MSC, Mesenchymal stem cells; FL-MSC, Fetal liver-derived Mesenchymal stem cells; BM-MSC, bone marrow Mesenchymal stem cells; UC-MSC, umbilical cord Mesenchymal stem cells; IDO, Indoleamine 2,3-dioxygenase; PGE2, Prostaglandin E2; TLR4, Toll-like Receptor 4; NK, Natural killer; TLR4+MSC, TLR4-positive MSC; IL-12, interleukin 12; IL-21, interleukin 21; NKG2D, type II integral membrane protein; IFN-γ, interferon-γ ; IFN-α, interferon-α.