T cell-monocyte interactions in the production of humoral factors regulating human granulopoiesis in vitro.
A variety of monocyte functions are modulated by the T cell lymphokine interferon-gamma (IFN-gamma). We assessed the capacity of IFN-gamma to induce release of granulocyte-monocyte stimulating factors (CSF-GM) from highly purified monocyte preparations. Whereas secretion of CSF-GM by monocytes is negligible in the absence of T cells, CSF-GM secretion is inducible when concentrations of IFN-gamma as low as 10 U/ml are present. This effect could be abrogated by specific neutralizing monoclonal antibody to IFN-gamma and was restricted to monocytes, as resting T cells failed to secrete detectable CSF-GM in response to IFN-gamma. The response of monocyte preparations to IFN-gamma was biphasic in that concentrations greater than 250 U/ml did not induce detectable CSF-GM activity. However, this was shown to be due to the release of a humoral inhibitor of G/M-progenitor cells, and not necessarily due to a lack of CSF-GM secretion.
Herrmann
F
F
Cannistra
S A
SA
Griffin
J D
JD
D002450:Cell Communication; D003115:Colony-Stimulating Factors / Q000096:biosynthesis* / Q000502:physiology; D006098:Granulocytes / Q000166:cytology; D006410:Hematopoiesis; D006412:Hematopoietic Stem Cells / Q000378:metabolism; D006801:Humans; D007371:Interferon-gamma / Q000494:pharmacology; D007399:Interphase; D009000:Monocytes / Q000166:cytology / Q000378:metabolism / Q000502:physiology*; D011506:Proteins / Q000378:metabolism; D013601:T-Lymphocytes / Q000502:physiology*
D003115:Colony-Stimulating Factors; D011506:Proteins; C016313:colony inhibiting factor; D007371:Interferon-gamma