PURPOSE: Many researchers have tried to develop animal models that mimic the human immune system, e.g. a humanized mouse model, to improve the engraftment of hematopoietic stem cells and develop human immune cells in an animal model. This study evaluated the feasibility of the cultured human umbilical cord blood (hUCB)-derived CD34(+) cells for cell expansion, in Rag2(-/-)gamma(c)(-/-) mice, and establish co-transplantation with human fetal thymus/liver tissue (Thy/Liv) under the kidney capsule. METHODS: Co-transplantation of hUCB-derived CD34(+) cells with Thy/Liv was performed. The hUCB-derived CD34(+) cells were prepared by freshly thawing (G1) and culturing for 7 days with two types of cytokine combinations (G2, G3). The CD45(+) cell populations were measured at 6, 8, 10 and 16 weeks in the peripheral blood. The splenocytes were cultured with mitogenic stimuli (PHA -L or IL-2) at 20 weeks post- transplantation, and the proliferation of human immune cells was evaluated. RESULTS: There were no significant differences in the human CD45(+) cell populations at 6, 8, 10 and 16 weeks post-transplantation between the groups. In the cultured splenocytes at 20 weeks post-transplant with PHA-L or IL-2, there was remarkable expansion of CD3(+) cells in the three groups. Although no CD19(+) cells were detected in the spleen, human Ig G was detected in the sera of these mice. CONCLUSION: The cultured and expanded hUCB-derived cells with cytokine combinations might be a feasible cell source in humanized mouse modeling. In addition, human immune cells can be reconstituted from the co-transplantation of Thy/Liv and cultured hUCB-derived CD34(+) cells.
Animals ; Fetal Blood ; Hematopoietic Stem Cells ; Humans ; Hydrazines ; Immune System ; Interleukin-2 ; Kidney ; Mice ; Models, Animal ; Phytohemagglutinins ; Spleen ; Transplants ; Umbilical Cord

BACKGROUND: While the number of deceased donor donations has increased in Korea, the organ shortage remains a major limitation for kidney transplantation. Donation after circulatory death (DCD) can be an option to expand the donor pool. In this study we evaluated the short and long term survival of grafts and patients and assessed the risk factors for graft failure. METHODS: In a single center, from August 1997 to December 2013, 28 cases of recipients who received kidney transplantation from DCD were enrolled. Information about donor and recipient factors, graft conditions, and transplant outcomes was collected through review of medical records. We calculated overall graft and patient survival rates and the risk factors for graft failure according to donor criteria and whether or not delayed graft function (DGF) occurred. RESULTS: There was no primary non-function, but DGF developed in 67.9% (19/28). Graft losses occurred in five patients during a median follow-up period of 68.2 months (4~204). There was no significant difference in graft survival rates depending on the donor criteria and the occurrence of DGF. In addition, there were no noteworthy risk factors for graft failure among donor age, donor creatinine, extended criteria donor, recipient age, warm ischemic time, cold ischemic time, and DGF. CONCLUSIONS: In this study, despite the high incidence of DGF, the long-term graft and patient survival in kidney transplantation from DCD were acceptable. Therefore, DCD can be an alternative to expand the donor pool and to shorten the waiting time.
Brain Death* ; Brain* ; Cold Ischemia ; Creatinine ; Delayed Graft Function ; Follow-Up Studies ; Graft Survival ; Humans ; Incidence ; Kidney Transplantation* ; Kidney* ; Korea* ; Medical Records ; Risk Factors ; Survival Rate ; Tissue Donors* ; Transplants ; Warm Ischemia