Bone marrow production of lung cells: the impact of G-CSF, cardiotoxin, graded doses of irradiation, and subpopulation phenotype.
OBJECTIVE
Previous studies have demonstrated the production of various types of lung cells from marrow cells under diverse experimental conditions. Our aim was to identify some of the variables that influence conversion in the lung.


METHODS
In separate experiments, mice received various doses of total-body irradiation followed by transplantation with whole bone marrow or various subpopulations of marrow cells (Lin(-/+), c-kit(-/+), Sca-1(-/+)) from GFP(+) (C57BL/6-TgN[ACTbEGFP]1Osb) mice. Some were given intramuscular cardiotoxin and/or mobilized with granulocyte colony-stimulating factor (G-CSF).


RESULTS
The production of pulmonary epithelial cells from engrafted bone marrow was established utilizing green fluorescent protein (GFP) antibody labeling to rule out autofluorescence and deconvolution microscopy to establish the colocaliztion of GFP and cytokeratin and the absence of CD45 in lung samples after transplantation. More donor-derived lung cells (GFP(+)/CD45(-)) were seen with increasing doses of radiation (5.43% of all lung cells, 1200 cGy). In the 900-cGy group, 61.43% of GFP(+)/CD45(-) cells were also cytokeratin(+). Mobilization further increased GFP(+)/CD45(-) cells to 7.88% in radiation-injured mice. Up to 1.67% of lung cells were GFP(+)/CD45(-) in radiation-injured mice transplanted with Lin(-), c-kit(+), or Sca-1(+) marrow cells. Lin(+), c-kit(-), and Sca-1(-) subpopulations did not significantly engraft the lung.


CONCLUSIONS
We have established that marrow cells are capable of producing pulmonary epithelial cells and identified radiation dose and G-CSF mobilization as variables influencing the production of lung cells from marrow cells. Furthermore, the putative lung cell-producing marrow cell has the phenotype of a hematopoietic stem cell.
Aliotta
Jason M
JM
Roger Williams Medical Center, Center for Stem Cell Biology, Providence, RI 02908, USA. jason.aliotta@verizon.net
Keaney
Patrick
P
Passero
Michael
M
Dooner
Mark S
MS
Pimentel
Jeffrey
J
Greer
Deborah
D
Demers
Delia
D
Foster
Bethany
B
Peterson
Abigail
A
Dooner
Gerri
G
Theise
Neil D
ND
Abedi
Mehrdad
M
Colvin
Gerald A
GA
Quesenberry
Peter J
PJ
D000818:Animals; D001854:Bone Marrow Cells / Q000166:cytology / Q000187:drug effects / Q000528:radiation effects; D016026:Bone Marrow Transplantation; D002454:Cell Differentiation / Q000187:drug effects / Q000528:radiation effects; D004179:Cobra Cardiotoxin Proteins / Q000008:administration & dosage*; D004307:Dose-Response Relationship, Radiation; D005260:Female; D005451:Fluorescein Angiography; D016179:Granulocyte Colony-Stimulating Factor / Q000008:administration & dosage*; D049452:Green Fluorescent Proteins / Q000378:metabolism; D007273:Injections, Intramuscular; D008168:Lung / Q000166:cytology / Q000187:drug effects / Q000528:radiation effects; D051379:Mice; D008810:Mice, Inbred C57BL; D010641:Phenotype; D014916:Whole-Body Irradiation
D004179:Cobra Cardiotoxin Proteins; D016179:Granulocyte Colony-Stimulating Factor; D049452:Green Fluorescent Proteins