Interleukin 3 promotes erythroid burst formation in "serum-free" cultures without detectable erythropoietin.

Abstract

Erythroid burst-forming units (BFU-E) from mouse bone marrow were grown for 7 days in agar or serumfree methylcellulose cultures in the presence or absence of erythropoietin (Ep) and/or interleukin 3 (IL-3). It was found that IL-3, even in the absence of serum and detectable Ep, was able to stimulate the full development of many erythroid bursts. This IL-3 effect was cell-dose dependent and did not appear to correlate with Ep dose. Spontaneous bursts and those stimulated by Ep only were rare and when seen were very small relative to those produced by IL-3 or IL-3 plus Ep. When addition of IL-3 or Ep to 7-day cultures was delayed, IL-3 but not Ep was shown to maintain BFU-E. No evidence was found by radioimmunoassay that Ep was produced or released in 7-day, "serum-free" cultures of bone marrow nor was Ep activity detected in culture media except those to which it had been added deliberately.Interleukin 3 (IL-3) began its interesting history as a factor believed to regulate early T-cell differentiation. This was based on the observation by Ihle that a factor in conditioned medium from activated T cells had the ability to induce expression of 20a-hydroxysteroid-dehydrogenase, an enzyme uniquely associated with the T-cell lineage, in splenic lymphocytes from athymic nude mice (1, 2). Ihle et al. (3) proposed that this factor, a glycoprotein of Mr 28,000, be called IL-3 and has since purified it to homogeneity (4). Activated T cells are believed to be the major source of IL-3, although WEHI-3, classified as a myelomonocytic leukemic cell line, produces it constitutively. In the short time since WEHI-3 was shown to produce IL-3, it has been found that the factor also has the ability to stimulate the growth in vitro of many kinds of hemopoietic cells (5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19) and it has been called by some a multispecific colony-stimulating factor (20).It has been shown to be identical with Schrader's P-cellstimulating factor (21) and with stem cell-activating factor (22).It has been recognized for some time that early erythroid progenitors require a second factor, burst-promoting activity (BPA), in addition to the hormone erythropoietin (Ep) for their full development in culture (23-26). The ability of IL-3 to stimulate erythropoiesis has been attributed to its activity as a burst promoter in the production of differentiated erythrocytes in vitro from the burst-forming progenitor or erythroid burst-forming units (BFU-E) (17, 27). It has been reported that under some circumstances "Ep-independent" BFU-E can develop (27-34). Evaluation of the site and nature of action of both BPA and Ep have, until recently, been burdened by the lack of highly purified material and by the presence of unknown quantities of BPA and Ep in constituents of culture media. Some crude preparations of Ep have been found to contain BPA as a contaminant (35). Now that a completely "serum-free" system has been devised (36) for the in vitro growth of erythroid bursts, it is possible to seek experimental answ...

Differential effects of an erythropoietin receptor gene disruption on primitive and definitive erythropoiesis.

“…Thus, our results show that signaling through the EpoR is not an obligatory step in the regulatory pathway leading to red cell differentiation, either in the definitive or in the primitive lineage. The ability of the mutant BFU-E and CFU-E to produce hemoglobinized red cells under these conditions is consistent with reports that SCF or IL-3 could support the differentiation of normal erythroid precursors in the absence of added Epo (Goodman et al 1985;Papayannopoulou et al 1993). On the other hand, the few EpoR-/-definitive erythrocytes that developed in vitro appeared to be smaller and less hemoglobinized than those in wild-type colonies.…”

Association between body size and selected hematological parameters in men and women aged 45 and above from a hospitalized population of older adults: an insight from the Polish Longitudinal Study of Aging (1960–2000)

“…Hematological parameters, such as RBC count, hematocrit level, and blood hemoglobin concentration, are partially related to each other by biochemical and physiological factors like oxygen deprivation (hypoxia), erythropoietin, interleukin-3, and other erythropoiesis-stimulating agents, including androgens, thyroid hormones, cortisol, and growth hormone (Meineke and Crafts 1968;Peschle et al 1972Peschle et al , 1978Golde et al 1977aGolde et al , 1977bGoodman et al 1985;Merchav et al 1988;Umemura et al 1989;Bijlani and Manjunatha 2011;Mathur et al 2011;Pimkin and Weiss 2012). Hypoxia is probably the most powerful physiological mechanism that promotes erythropoiesis, and the kidneys are the most sensitive oxygen sensors involved in mediating the hypoxic induction of the production of RBCs by the red bone marrow (Goldberg et al 1988(Goldberg et al , 1989Haase 2010).…”

Erythropoietin changes the globin program of an interleukin 3-dependent multipotential cell line.

“…Although it is widely accepted that the birth of erythroid lineage-committed progenitors is not dependent on Epo (30,31), the Epo-independent expression of a terminal erythroid differentiation program remains controversial (32)(33)(34). Our detection of globin in cells cultured in the presence of an Epo-neutralizing antibody suggests that IL-3 may be adequate to support terminal erythroid differentiation.…”