352:
Human iPSC-derived MSC negatively modulates ILC2 by PDL1/2
Sunday, March 4, 2018
South Hall A2 (Convention Center)
Chenglin Li, Zhibin Xu, Zili Qin, Yaqi Pen, Qingling Fu
RATIONALE:

T helper 2 cells(Th2) and group 2 innate lymphoid cells (ILC2s) were reported to serve a critical role in allergic inflammation development by producing large amounts of IL-5 and IL-13 under allergen. Mesenchymal stem cells were reported to suppress Th2 and ease allergy inflammation. However, whether MSC negatively modulated ILC2 is unknown.

METHODS:

Human PBMC or ILC2 were isolated and stimulated with IL2/25/33. The effect of iPSC-MSCs on ILC2 in co-culture with or without transwell or by intravenous injection of iPSC-MSCs to IL-33 induced mice model. IL-5 and IL-13 expression were examined in protein and mRNA level. PDL1 and PDL2 expression in iPSC-MSCs were examined using flow cytometry.

RESULTS:

PBMCs from allergic rhinitis and asthma patients were more sensitive to epithelium-derived cytokines than health group. In co-culture, human induced pluripotent stem cells (iPSCs)-derived MSCs (iPSC-MSCs) significantly reduced IL2/25/33 induced IL-5 and IL-13 production by ILC2, which was reversed by transwell separation. iPSC-MSCs expressed higher PDL1 and PDL2 than control. Both PDL2 and PDL1 reduced IL2/25/33 induced IL-5 and IL13 expression in ILC2; however, PDL2 showed a stronger suppressive effect than PDL1. In IL-33 induced allergy inflammation mice model, MSC reduced IL-13 expression in bronchoalveolar lavage fluid and the score of PAS staining.

CONCLUSIONS:

Human iPSC-MSCs showed a suppressive effect on ILC2, which was dependent of cell-to-cell contact. These effect may be caused by PDL1 and PDL2.