Allogeneic non-adherent bone marrow cells facilitate hematopoietic recovery but do not lead to allogeneic engraftment.
BACKGROUND
Non adherent bone marrow derived cells (NA-BMCs) have recently been described to give rise to multiple mesenchymal phenotypes and have an impact in tissue regeneration. Therefore, the effects of murine bone marrow derived NA-BMCs were investigated with regard to engraftment capacities in allogeneic and syngeneic stem cell transplantation using transgenic, human CD4(+), murine CD4(-/-), HLA-DR3(+) mice.


RESULTS
Bone marrow cells were harvested from C57Bl/6 and Balb/c wild-type mice, expanded to NA-BMCs for 4 days and characterized by flow cytometry before transplantation in lethally irradiated recipient mice. Chimerism was detected using flow cytometry for MHC-I (H-2D[b], H-2K[d]), mu/huCD4, and huHLA-DR3). Culturing of bone marrow cells in a dexamethasone containing DMEM medium induced expansion of non adherent cells expressing CD11b, CD45, and CD90. Analysis of the CD45(+) showed depletion of CD4(+), CD8(+), CD19(+), and CD117(+) cells. Expanded syngeneic and allogeneic NA-BMCs were transplanted into triple transgenic mice. Syngeneic NA-BMCs protected 83% of mice from death (n = 8, CD4(+) donor chimerism of 5.8+/-2.4% [day 40], P<.001). Allogeneic NA-BMCs preserved 62.5% (n = 8) of mice from death without detectable hematopoietic donor chimerism. Transplantation of syngeneic bone marrow cells preserved 100%, transplantation of allogeneic bone marrow cells 33% of mice from death.


CONCLUSIONS
NA-BMCs triggered endogenous hematopoiesis and induced faster recovery compared to bone marrow controls. These findings may be of relevance in the refinement of strategies in the treatment of hematological malignancies.
Fricke
Stephan
S
Fraunhofer Institute for Cell Therapy and Immunology (IZI), Leipzig, Germany. stephan.fricke@izi.fraunhofer.de
Ackermann
Manuela
M
Stolzing
Alexandra
A
Schimmelpfennig
Christoph
C
Hilger
Nadja
N
Jahns
Jutta
J
Hildebrandt
Guido
G
Emmrich
Frank
F
Ruschpler
Peter
P
Pösel
Claudia
C
Kamprad
Manja
M
Sack
Ulrich
U
D000818:Animals; D015703:Antigens, CD / Q000276:immunology; D001854:Bone Marrow Cells / Q000166:cytology* / Q000276:immunology; D016026:Bone Marrow Transplantation; D002448:Cell Adhesion; D002455:Cell Division; D003470:Culture Media; D005434:Flow Cytometry; D016130:Immunophenotyping; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D014184:Transplantation, Homologous
D015703:Antigens, CD; D003470:Culture Media