The cytokine production by human erythroid nuclear cells

It was demonstrated earlier that murine erythroid nuclear cells are capable of expressing the mRNA of multiple cytokine genes. The purpose of this research was to study the ability of erythroid cells to produce various cytokines. Enriched population of erythroid cells was obtained from the human fetal liver by negative and positive selection methods using antibodies against erythroblast antigenes (HAE-9 or Glycophorin A). Quantitative production of the cytokines was measured by electrochemiluminescence. We have found that the human erythroid nuclear cells produce cytokines such as IL-1β, IL-2, IL-4, IL-6, TNF-α and IFN-γ. It is known that production of these cytokines can change qualitatively and quantitatively after mitogen (LPS, ConA) and Epo stimulation. The level of IL-1β produced by cells after cultivation with Epo was significantly reduced, but increased after addition of mitogens. Conversely the production of IL-2 and IL-4 significantly increased after Epo cultivation and was reduced after mitogen stimulation. IL-6 production decreased under the influence of Epo and decreased even more after adding mitogen to the culture medium. Low IFN-γ and TNF-α production was shown for the erythroid cells; however it increased sharply after Epo stimulation. The negative feedback in regulation of erythropoiesis can be achieved through TNF-α and IFN-γ. Levels of cytokine production by erythroid cells were comparable with cytokine production by human PBMC after mitogen stimulation. The cytokine-synthetic activity of erythroid cells led us to consider it along with other immunopoietic cell lines, and to take a new look on the role of erythroid cells in self-renewal and regulation of haemo- and immunopoiesis.