The effects of rM-CSF and rIL-6 therapy on immunosuppressed antiorthostatically suspended mice.
Antiorthostatically suspended mice had suppressed macrophage development in both unloaded and loaded bones, indicating a systemic effect. Bone marrow cells from those mice secreted less macrophage colony-stimulating factor (M-CSF) and interleukin-6 (IL-6) than did control mice. Because M-CSF and IL-6 are important to bone marrow macrophage maturation, we formulated the hypothesis that suppressed macrophage development occurred as a result of the depressed levels of either M-CSF or IL-6. To test the hypothesis, mice were administered recombinant M-CSF or IL-6 intraperitoneally. We showed that recombinant M-CSF therapy, but not recombinant IL-6 therapy, reversed the suppressive effects of antiorthostatic suspension on macrophage development. These data suggest that bone marrow cells that produce M-CSF are affected by antiorthostatic suspension and may contribute to the inhibited maturation of bone marrow macrophage progenitors.
Armstrong
J W
JW
Division of Biology, Kansas State University, Manhattan 66506, USA.
Kirby-Dobbels
K
K
Chapes
S K
SK
D000818:Animals; D001854:Bone Marrow Cells; D002455:Cell Division; D016922:Cellular Senescence; D016207:Cytokines / Q000378:metabolism; D006410:Hematopoiesis / Q000502:physiology; D007165:Immunosuppression Therapy; D015850:Interleukin-6 / Q000494:pharmacology*; D016173:Macrophage Colony-Stimulating Factor / Q000494:pharmacology*; D008264:Macrophages / Q000502:physiology; D008297:Male; D051379:Mice; D008809:Mice, Inbred C3H; D011187:Posture; D011994:Recombinant Proteins; D013312:Stress, Physiological / Q000503:physiopathology; D013601:T-Lymphocytes / Q000166:cytology; D016474:Weight-Bearing
D016207:Cytokines; D015850:Interleukin-6; D011994:Recombinant Proteins; D016173:Macrophage Colony-Stimulating Factor