Nucleated red blood cells (NRBCs) are precursors of red blood cells (RBCs), but also possess variety of immunomodulatory effects. However, among the three types of NRBCs, the immunological effects of human CD45- NRBCs remain largely unknown. We have previously shown that cord blood-derived CD45- NRBCs and adult peripheral blood-derived monocytes cocultured in a lipopolysaccharide (LPS)-stimulated indirect coculture system that avoided cell-to-cell contact, increase IL-10 and decrease TNF-