Intra-bone marrow injection of bone marrow and cord blood cells: an alternative way of transplantation associated with a higher seeding efficiency.
OBJECTIVE
Intravenous (IV) injection is currently the normal method for transplanting hematopoietic cells. However, the problem of seeding efficiency and homing is relevant especially when a limited number of stem cells is available. Intra-bone marrow (IBM) injection of bone marrow cells (BMCs) may overcome this problem.


METHODS
Irradiated (750 cGy) C57BL/6J mice were transplanted with 1 x 10(5) BMCs harvested from transgenic mice expressing an enhanced version of the green fluorescent protein (EGFP+) via IBM or with 1 x 10(6) EGFP+ BMCs via IV. Irradiated (320 cGy) NOD/SCID mice were transplanted with 1 x 10(6) human cord blood (CB) cells via IBM or with 1 x 10(7) human CB cells via IV.


RESULTS
In C57BL/6J mice after 90 days, the fraction of EGFP+ cells harvested was 37% and 53% in IV-treated and IBM-treated (contralateral tibia and femur in the IBM) mice, respectively: the expansion folds were 114 and 1760, respectively. In NOD/SCID mice, the percentages of CD45+ cells and CD45+/CD34+ cells were, at 30 days, 3.3% and 0.3% in IV-treated mice, and 4.4% and 1.1% in IBM-treated mice. At 60 days, the percentages of CD45+ cells and CD45+/CD34+ cells were 2.1% and 0.3% in IV-treated mice and 1.4% and 0.4% in IBM-treated mice. At day 90 the percentages of CD45+ cells and CD45+/CD34+ cells were 3% and 0.3% in IV-treated mice and 2.3% and 0.4% in IBM-treated mice.


CONCLUSIONS
Our data demonstrate that IBM transplantation is associated with a seeding efficiency 15 times greater than IV transplantation. IBM transplantation may improve the results of transplant and may be useful in several settings: 1) when a limited number of hematopoietic progenitors are available; and 2) in experiments aiming to place in the bone marrow stem cells of other lineages (CNS, muscle, etc.).
Centro Cellule Staminali e Terapia Cellularee, Università di Pavia, Italy.
Sandra
S
Castello
Marina
M
Podestà
Vincenzo G
VG
Menditto
Adalberto
A
Ibatici
Anna
A
Pitto
Osvaldo
O
Figari
Daniele
D
Scarpati
Lorenzo
L
Magrassi
Andrea
A
Bacigalupo
Giovanna
G
Piaggio
Francesco
F
Frassoni
D000818:Animals; D002455:Cell Division; D036101:Cord Blood Stem Cell Transplantation / Q000379:methods*; D049452:Green Fluorescent Proteins; D018380:Hematopoietic Stem Cell Transplantation / Q000379:methods*; D006801:Humans; D008164:Luminescent Proteins / Q000032:analysis; D051379:Mice; D008810:Mice, Inbred C57BL
D008164:Luminescent Proteins; D049452:Green Fluorescent Proteins