Embodiments disclosed here provide engineered modified hematopoietic stem cells (HSCs), artificially prostaglandin E2 (PGE2)-stimulated HSCs, compositions comprising these HSCs, methods of using these modified HSCs for treating autoimmune diseases and disorders and for suppressing the immune system. In particular, the engineered modified HSCs or PGE2-stimulated HSCs express the surface marker, programmed cell death-1 ligand 1 (PD-L1).