从异体和自体 CD34(+) 造血祖细胞生成人 ILC3 用于过继转移

Type 3 innate lymphoid cells (ILC3) are important in tissue homeostasis. In the gut, ILC3 repair damaged epithelium and suppress inflammation. In allogeneic hematopoietic cell transplantation (HCT), ILC3 protect against graft-versus-host disease (GvHD), most likely by restoring tissue damage and preventing inflammation.

We hypothesize that supplementing HCT grafts with interleukin-22 (IL-22)-producing ILC3 may prevent acute GvHD.

We therefore explored ex vivo generation of human IL-22-producing ILC3 from hematopoietic stem and progenitor cells (HSPC) obtained from adult, neonatal and fetal sources.

We established a stroma-free system culturing human cord blood-derived CD34 + HSPC with successive cytokine mixes for 5 weeks.

We analyzed the presence of phenotypically defined ILC, their viability, proliferation and IL-22 production (after stimulation) by flow cytometry and enzyme-linked immunosorbent assay (ELISA).

We found that the addition of recombinant human IL-15 and the enhancer of zeste homolog 1/2 inhibitor UNC1999 promoted ILC3 generation. Similar results were demonstrated when UNC1999 was added to CD34 + HSPC derived from healthy adult granulocyte colony-stimulating factor mobilized peripheral blood and bone marrow, but not fetal liver. UNC1999 did not negatively impact IL-22 production in any of the HSPC sources.

Finally, we observed that autologous HSPC mobilized from the blood of adults with hematological malignancies also developed into ILC3, albeit with a significantly lower capacity.

Together, we developed a stroma-free protocol to generate large quantities of IL-22-producing ILC3 from healthy adult human HSPC that can be applied for adoptive transfer to prevent GvHD after allogeneic HCT.