Engraftment kinetics of human CD34+ cells from cord blood and mobilized peripheral blood co-transplanted into NOD/SCID mice.
We have reported short periods of post transplant neutropenia in human patients co-transplanted with cord blood (CB) and low numbers of haploidentical mobilized peripheral blood (MPB) CD34+ cells. To investigate the effect that the proportion of MPB to CB cells may have on engraftment kinetics, we have co-transplanted fixed numbers of human CB CD34+ cells mixed with different numbers of MPB CD34+ cells into NOD/SCID mice. We periodically quantified the proportion of human cells and the relative contribution of MPB and CB cells to the human engraftment on marrow aspirates. At the lowest MPB/CB ratios (5 : 1, 10 : 1), the contribution of CB cells predominated at all time points analyzed, and in three out of four experiments MPB cell contributions progressively decreased from day +15. At higher MPB/CB ratios, MPB cells had a more important contribution to both early and late engraftment, with the highest cell ratio resulting in only marginal CB cell engraftment. Therefore, our results showed greater potential, on a per cell basis, of human CB vs MPB cells for competitive sustained engraftment in the xenogeneic model used, which was only abrogated by the co-infusion of very high numbers of MPB cells.
Ramírez
M
M
Unidad de Hematopoyesis, CIEMAT, Hospital Puerta de Hierro, Universidad Autónoma de Madrid, Madrid, Spain.
Regidor
C
C
Marugán
I
I
García-Conde
J
J
Bueren
J A
JA
Fernández
M N
MN
D000818:Animals; D018952:Antigens, CD34; D036101:Cord Blood Stem Cell Transplantation; D006085:Graft Survival; D006801:Humans; D007700:Kinetics; D051379:Mice; D016688:Mice, Inbred NOD; D016513:Mice, SCID; D023421:Models, Animal; D009503:Neutropenia / Q000209:etiology; D036102:Peripheral Blood Stem Cell Transplantation; D014183:Transplantation, Heterologous
D018952:Antigens, CD34