Cytokine-Synthesizing Activity of Erythroid Cells.
The presence of mRNA of cytokines IL-1alpha, IL-1beta, IL-4, IL-6, IFN-gamma, TGF-beta, GM-CSF and the absence of mRNA of IL-2, IL-3 and IL-5 were identified in erythroid cells isolated from spleen of mice subjected to erythropoiesis-stimulating actions (treated with phenylhydrazine, acute hypoxia) and from spleen of newborn mice. Gene expression of cytokines in erythroid cells therewith differed both qualitatively and quantitatively depending on erythropoiesis-stimulating action. Erythroid cells of newborn mice contained mRNA of GM-CSF, but did not contain mRNA of IFN-gamma, whereas erythroid cells of mice under acute hypoxia or treated with phenylhydrazine had mRNA of IFN-gamma, but no mRNA of GM-CSF. After cell cultivation with erythropoietin, qualitative and quantitative changes in gene expression of cytokines were observed including the appearance of mRNA of IL-2, IL-3 but not of IL-5. The fact of gene expression of cytokines was confirmed on cells from single erythroid colonies. The level of mRNA expression of cytokines in erythroid cells was comparable with, and for a number of cytokines even higher than in splenocytes of mice immunized with T-dependent antigen. Moreover, it was demonstrated that erythroid cells are capable of translating proteins themselves. The production of GM-CSF and IFN-gamma by erythroid cells extracted from spleen of newborn mice, as well as from mice after erythropoiesis-stimulating actions (treatment with phenylhydrazine, acute hypoxia, acute blood loss) was detected. The level of IFN-gamma production was comparable with the level of production of this cytokine by mitogen-stimulated splenocytes. Thus, erythroid cells, as well as the cells of practically all hemopoietic lineages are capable to express and produce a number of hemo- and immunoregulatory cytokines by means of which they can participate in the regulation of hemo- and immunopoiesis, as well as exert a self-regulatory lineage restricted effect on cell proliferation and differentiation.
Sennikov
Sergey V.
SV
Institute of Clinical Immunology, Siberian Branch of Russian Academy of Medical Sciences, Novosibirsk, Russia.
Eremina
Larissa V.
LV
Injelevskaya
Tatajana V.
TV
Krysov
Sergey V.
SV
Silkov
Alexandr N.
AN
Kozlov
Vladimir A.
VA