Chemokine expression in human erythroid leukemia cell line AS-E2: macrophage inflammatory protein-3alpha/CCL20 is induced by inflammatory cytokines.
OBJECTIVE
Normal and malignant hematopoietic cells are shown to express and secrete various cytokines and chemokines, some of which are believed to play an important role in normal and abnormal hematopoiesis in an autocrine/paracrine manner. To explore the possibility of a cytokine/chemokine network participating in the pathophysiology of anemic disorders, we evaluated the ability of inflammatory cytokines to induce chemokine expression using erythroid progenitor cells.


METHODS
Erythropoietin-dependent human leukemia cell line AS-E2 was used as a model of erythroid colony-forming unit (CFU-E) cells. The expression of mRNA of 8 chemokines was examined using RT-PCR, before and after TNF-alpha, IFN-gamma, and IL-1beta stimulation. For MIP-3alpha, the promoter activity was analyzed by luciferase assay and secretion was confirmed by ELISA. The expression of CCR6, the specific receptor for MIP-3alpha, was analyzed by RT-PCR and flow cytometry.


RESULTS
Unstimulated AS-E2 cells constitutively expressed transcripts for MCP-4, IP-10, PF-4, IL-8, and MIP-3alpha. Stimulation with TNF-alpha, IFN-gamma, and IL-1beta upregulated MIP-3alpha mRNA expression and induced its protein secretion. Luciferase assay revealed that these cytokines could upregulate promoter activity of the MIP-3alpha gene, possibly through the NF-kappaB pathway. CCR6 mRNA was detected and its intracellular expression was confirmed.


CONCLUSIONS
These data suggest that inflammatory cytokine-stimulated erythroid progenitors secrete MIP-3alpha, which may function in an autocrine/paracrine manner. Furthermore, the existence of intracellular CCR6 suggests the involvement in cytokine signaling of a MIP-3alpha-dependent internal autocrine mechanism. These mechanisms may play a role in pathophysiology of anemic disorders, such as secondary anemia and bone marrow failure syndromes.
Inoue
Yoriko
Y
Department of Hematology, Molecular Medicine Unit, Atomic Bomb Disease Institute, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan.
Tsushima
Hideki
H
Ando
Koji
K
Sawayama
Yasushi
Y
Sakai
Mari
M
Yamasaki
Reishi
R
Matsuo
Emi
E
Tsutsumi
Chizuko
C
Imaizumi
Yoshitaka
Y
Iwanaga
Masako
M
Imanishi
Daisuke
D
Taguchi
Jun
J
Miyazaki
Yasushi
Y
Tomonaga
Masao
M
D045744:Cell Line, Tumor; D054418:Chemokine CCL20; D018925:Chemokines / Q000096:biosynthesis / Q000235:genetics*; D019742:Chemokines, CC / Q000378:metabolism*; D016207:Cytokines / Q000494:pharmacology*; D004797:Enzyme-Linked Immunosorbent Assay; D015672:Erythroid Precursor Cells / Q000187:drug effects / Q000378:metabolism*; D004921:Erythropoietin / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects / Q000276:immunology; D006801:Humans; D007249:Inflammation; D007375:Interleukin-1 / Q000494:pharmacology; D004915:Leukemia, Erythroblastic, Acute / Q000378:metabolism*; D019402:Macrophage Inflammatory Proteins / Q000378:metabolism*; D011401:Promoter Regions, Genetic / Q000187:drug effects / Q000502:physiology; D012333:RNA, Messenger / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D054399:Receptors, CCR6; D019707:Receptors, Chemokine / Q000187:drug effects / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
C108355:CCL20 protein, human; C106311:CCR6 protein, human; D054418:Chemokine CCL20; D018925:Chemokines; D019742:Chemokines, CC; D016207:Cytokines; D007375:Interleukin-1; D019402:Macrophage Inflammatory Proteins; D012333:RNA, Messenger; D054399:Receptors, CCR6; D019707:Receptors, Chemokine; D014409:Tumor Necrosis Factor-alpha; D004921:Erythropoietin