Fast hematopoietic recovery after bone marrow engraftment needs physiological proximity of stromal and stem cells.
Relatively slow hematopoietic recovery after isolated bone marrow (I-BM) engraftment is probably caused by a disrupted microenvironment of stromal and stem cells. Thus, we compared the kinetics of hematopoietic recovery of lethally irradiated rats that received I-BM versus vascularized BM (V-BM). Total body irradiated (TBI; 8 Gy) Lewis (LEW; RT1(1)) rats were either injected IV with syngeneic sex-mismatched 80 x 10(6) I-BM or transplanted with 80 x 10(6) V-BM in orthotopic hind limb grafts. Ten days later, peripheral blood (PB) and mesenteric lymph nodes (MLN) of these recipients were examined for the presence of donor-derived hematopoietic cells with a panel of monoclonal antibodies by FACS. To detect male cells in sex-mismatched female recipients, PCR was performed using male Y chromosome primers. When examined in PB and MLN, recipients transplanted with V-BM displayed significantly faster recovery of leukocytes (CD43+), monocytes (CD14+), and T cells (CD5+) in comparison with I-BM recipients. In addition, only V-BM (but not I-BM) groups contained stroma-like male-positive cells in PB and MLN. Our results suggest that V-BM transplants provided superior hematopoietic recovery in comparison to I-BM transplants. We postulated that close proximity between stromal and stem cells in V-BM is essential for efficient repopulation with progenitors of different lines of leukocytes.
Janczewska
Slawa
S
Surgical Research and Transplantology Department, Medical Research Center, Polish Academy of Sciences, Warsaw, Poland. Slawa.Janczewska@uth.tmc.edu
Wisniewski
Marcin
M
Stepkowski
Stanislaw M
SM
Lukomska
Barbara
B
D000818:Animals; D000906:Antibodies; D016026:Bone Marrow Transplantation / Q000379:methods*; D002450:Cell Communication / Q000276:immunology; D002455:Cell Division / Q000276:immunology; D005260:Female; D006085:Graft Survival / Q000276:immunology*; D006412:Hematopoietic Stem Cells / Q000276:immunology*; D008198:Lymph Nodes / Q000166:cytology / Q000276:immunology; D008297:Male; D009000:Monocytes / Q000166:cytology / Q000276:immunology; D051381:Rats; D011917:Rats, Inbred Lew; D012038:Regeneration / Q000276:immunology*; D013234:Stem Cells / Q000166:cytology / Q000276:immunology; D017154:Stromal Cells / Q000276:immunology*; D013601:T-Lymphocytes / Q000166:cytology / Q000276:immunology
D000906:Antibodies