The effect of reduced oxygen tension on colony formation of erythropoietic cells in vitro

Abstract

The effect of reduced oxygen tension and the role of cellular components known to protect the cell against oxygen toxicity has been studied with respect to erythropoietic colony formation in vitro. Alphathioglycerol can be partially replaced by vitamin E and completely replaced by reduced glutathione (GSH) at physiological concentrations. Incubation of bone marrow and fetal liver early (BFU-E) and late (CFU-E) erythropoietic progenitor cells, in the presence of GSH, in an atmosphere containing 5% oxygen, 5% carbon dioxide and 90% nitrogen, as opposed to air supplemented with 5% carbon dioxide, resulted in an increase in colony numbers and response to erythropoietin (Epo). The number of colonies derived from bone marrow and fetal liver CFU-E increased by 1.2--2.8-fold with a relative Epo sensitivity increase of 3.5--4-fold. Bursts obtained from bone marrow and fetal liver BFU-E increased from 2.6- to 3.8-fold with an increased response to Epo of 2--3-fold. The effects of GSH and low oxygen tension are interpreted as causing a reduction in oxygen toxicity of the cells, thereby increasing the life span in vitro and so increasing the number of cells capable of forming colonies. The heightened response of BFU-E to Epo, analogous to the effect seen for CFU-E, implies that BFU-E may be responsive to physiological Epo concentrations at physiological oxygen tensions.

Modulation of tumour cell colony growth in soft agar by oxygen and its mechanism

“…The formation of hydrogen peroxide, hydroxyl radicals and lipid peroxidation did not appear to be of major importance since chemical scavengers of these reaction products did not influence EAT cell colony formation. These data with EAT cells are similar to the results reported for the beneficial effect of GSH at 20% 02 on erythroid colony forming units (Rich & Kuanek, 1982) and oc-thioglycerol on granulocytic precursors (Bradley et al, 1978). The results with EAT cells are different from that reported for beneficial effect of Vitamin E on erythroid cells (Rich & Kuanek, 1982).…”

“…This effect has been reported for solid tumour cells, lymphoma, lymphoblastic leukaemia stem cells, fibroblasts, granulocyte-macrophage precursors, and erythroid colony forming units (Bradley et al, 1978;Izaguirre et al, 1981;Smith et al, 1981;Gupta & Krishan, 1982;Rich & Kuanek, 1982). The concept for use of low 02 concentration for colony formation relates to the observation that physiological 02 level in normal and tumour tissues are in the range of 2-5% 02 (15-40mmHg) and 0.1-5%02 (2-40mmHg) respectively, white arterial values are in the range of 10-15%02 (80-100mmHg) (Carter & Silver, 1960;Van den Brenk, 1964 and1965; Kolstad, 1968;and Vaupel et al, 1981).…”

Enhanced growth of myelodysplastic colonies in hypoxic conditions

“…Such a lesion would permit unlimited self-renewal of MDS-initiating cells, provided these cells stayed at an oxygen tension comparable to that of the HSC niche. Consistent with our hypothesis, we demonstrate here that MDS progenitor cells cultured in both 3% O 2 and 1% O 2 demonstrate an augmentation of colony-forming unit (CFU) yield far in excess of what has previously been described in normal progenitors [67][68][69][70][71][72][73][74][75][76]. This degree of augmentation with physiologic oxygen was not observed in either acute or chronic myelogenous leukemias, but was maintained following the removal of CD34 − accessory cells.…”

Role of the plasma membrane ROS-generating NADPH oxidase in CD34+ progenitor cells preservation by hypoxia

“…It is known that oxygen concentration is one of the important factors for proliferation and differentiation of HSPCs ex vivo (McAdams et al, 1996). For cultivation ex vivo, low levels of oxygen favored the proliferation of colony-forming cells (CFCs) (Broxmeyer et al, 1990;Rich and Kubanek, 1982), HSPCs (Koller et al, 1992a,b), and mature granulocytes (Hevehan et al, 2000). However, high…”