Radiation-induced increase in plasma Flt3 ligand concentration in mice: evidence for the implication of several cell types.
Circulating T lymphocytes were proposed as the main producer of Flt3 ligand. However, during aplasia, there is a drastic reduction in the number of T lymphocytes, while plasma Flt3 ligand concentration is increased. This contradiction prompted us to compare variations in plasma Flt3 ligand during radiation-induced aplasia in BALB/c mice and in T-lymphocyte-deficient NOD-SCID mice to delineate the role of T lymphocytes in the increase in Flt3 ligand concentration. The results showed that plasma Flt3 ligand concentration was increased similarly in the two strains of mice, and that Flt3 ligand concentration was negatively correlated to the number of residual hematopoietic progenitors. Moreover, the Flt3 ligand mRNA expression and Flt3 ligand protein concentration were similar in the two strains of mice in all organs tested, i.e. thymus, spleen, bone marrow, liver, brain and blood cells. These results confirm that Flt3 ligand concentration in the blood is a reflection of bone marrow function and that T lymphocytes are not the main regulator of Flt3 ligand variations during aplasia.
Prat
Marie
M
Institut de Radioprotection et de Sûreté Nucléaire, DRPH/SRBE, Fontenay aux roses, France. marie.prat@irsn.fr
Demarquay
Christelle
C
Frick
Johanna
J
Thierry
Dominique
D
Gorin
Norbert-Claude
NC
Bertho
Jean Marc
JM
D000818:Animals; D004307:Dose-Response Relationship, Radiation; D008297:Male; D008565:Membrane Proteins / Q000097:blood*; D008657:Metabolic Clearance Rate; D051379:Mice; D008807:Mice, Inbred BALB C; D009928:Organ Specificity; D011829:Radiation Dosage; D011832:Radiation Injuries / Q000209:etiology* / Q000378:metabolism*; D012010:Red-Cell Aplasia, Pure / Q000209:etiology* / Q000378:metabolism*; D014018:Tissue Distribution; D014916:Whole-Body Irradiation / Q000009:adverse effects*
D008565:Membrane Proteins; C084881:flt3 ligand protein