Perturbation of autocrine/paracrine loops of burst-forming units of erythroid-derived cells in rHuEPO-hyporesponsive hemodialysis patients.
BACKGROUND
Quantitative or qualitative abnormalities of erythroid progenitors in patients with chronic renal failure (CRF) could be the major factor for recombinant human erythropoietin (rHuEPO) hyporesponsiveness and severe anemia in hemodialysis (HD) patients receiving rHuEPO therapy.


METHODS
Purified 1 x 10(4) circulating CD34+ cells isolated from rHuEPO-hyporesponsive HD patients (EPO-H; n = 10), rHuEPO-responsive non-HD patients with CRF (EPO-R; n = 8), nonanemic HD patients without rHuEPO therapy (EPO-W/O; n = 10), and healthy volunteer controls (CON; n = 10) were subjected to a methylcellulose culture system supplemented with rHuEPO, recombinant human interleukin-3 (IL-3), recombinant human stem cell factor (SCF), and recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF) for 14 days.


RESULTS
The average number of burst-forming units of erythroids (BFU-Es) was significantly less in the EPO-H group compared with the CON and EPO-W/O groups. Furthermore, colony size also was significantly smaller in the EPO-H group. Total RNAs were extracted from approximately 100 colonies/patient and subjected to complementary DNA expression array studies of 268 growth factors, cytokines, chemokines, and their receptors. A characteristic cluster upregulated in the EPO-R and EPO-W/O groups and downregulated in the EPO-H group was identified that contained various cytokines and growth factors, including IL-6, GM-CSF, vascular endothelial growth factor B, IL-9, IL-3, leukemia inhibitory factor, and interferon alpha-2, and such receptors as thrombopoietin receptor, IL-9 receptor, and colony-stimulating factor 1 receptor.


CONCLUSIONS
These data suggest that the cross-talk network or autocrine/paracrine regulatory loop is critically impaired in BFU-E-derived cells in EPO-H patients, and investigation of these cluster genes would facilitate the development of novel therapeutic strategies for such patients.
Nakao
Kazushi
K
Department of Medicine and Clinical Science, Okayama University Graduate School of Medicine and Dentistry, Okayama, Japan.
Wada
Jun
J
Ota
Kosuke
K
Ichikawa
Haruo
H
Akagi
Shigeru
S
Okamoto
Akira
A
Hida
Kazuyuki
K
Nagake
Yoshio
Y
Makino
Hirofumi
H
D000368:Aged; D018952:Antigens, CD34 / Q000378:metabolism; D019898:Autocrine Communication / Q000187:drug effects* / Q000235:genetics; D002478:Cells, Cultured; D016000:Cluster Analysis; D003114:Colony-Forming Units Assay / Q000706:statistics & numerical data; D003199:Computer Systems / Q000706:statistics & numerical data; D015672:Erythroid Precursor Cells / Q000737:chemistry / Q000187:drug effects* / Q000378:metabolism* / Q000473:pathology; D004921:Erythropoietin / Q000378:metabolism* / Q000627:therapeutic use; D005260:Female; D020869:Gene Expression Profiling / Q000706:statistics & numerical data; D005786:Gene Expression Regulation / Q000187:drug effects / Q000235:genetics; D005796:Genes / Q000235:genetics; D006801:Humans; D007676:Kidney Failure, Chronic / Q000097:blood / Q000188:drug therapy / Q000235:genetics / Q000628:therapy; D008297:Male; D020411:Oligonucleotide Array Sequence Analysis / Q000706:statistics & numerical data; D019899:Paracrine Communication / Q000187:drug effects* / Q000235:genetics; D011994:Recombinant Proteins; D006435:Renal Dialysis; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000706:statistics & numerical data
D018952:Antigens, CD34; D011994:Recombinant Proteins; D004921:Erythropoietin