Interleukin-6 aborts lymphopoiesis and elevates production of myeloid cells in systemic lupus erythematosus-prone B6.Sle1.Yaa animals.
We previously reported the inhibitory action of interleukin-6 (IL-6) on B lymphopoiesis with SHIP(-/-) mice and showed that IL-6 biases lineage commitment toward myeloid cell fates in vitro and in vivo. Because elevated IL-6 is a feature of chronic inflammatory diseases, we applied an animal model of systemic lupus erythematosus (SLE) to determine whether IL-6 has similar effects on hematopoiesis. We found that IL-6 levels were elevated in the B6.Sle1.Yaa mice, and the increase was accompanied by losses of CD19(+) B cells and more primitive B-lymphoid progenitors in bone marrow. Both the CD19(+) B-cell population and their progenitors recovered in an IL-6(-/-) background. The uncommitted progenitors, containing precursors for both lymphoid and myeloid fates, expressed IL-6 receptor-alpha chain and responded to IL-6 by phosphorylation of STAT3. IL-6 stimulation caused uncommitted progenitors to express the Id1 transcription factor, which is known to inhibit lymphopoiesis and elevate myelopoiesis, and its expression was MAPK dependent. We conclude that chronic inflammatory conditions accompanied by increased IL-6 production bias uncommitted progenitors to a myeloid fate by inducing Id1 expression.
Maeda
Kenichiro
K
Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA.
Malykhin
Alex
A
Teague-Weber
Brittany N
BN
Sun
Xiao-Hong
XH
Farris
A Darise
AD
Coggeshall
K Mark
KM
D000818:Animals; D018941:Antigens, CD19 / Q000378:metabolism; D001402:B-Lymphocytes / Q000378:metabolism / Q000473:pathology; D002454:Cell Differentiation; D002478:Cells, Cultured; D016895:Culture Media, Serum-Free; D004195:Disease Models, Animal; D004797:Enzyme-Linked Immunosorbent Assay; D005434:Flow Cytometry; D015850:Interleukin-6 / Q000502:physiology*; D008180:Lupus Erythematosus, Systemic / Q000209:etiology / Q000473:pathology*; D038041:Lymphopoiesis / Q000502:physiology*; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D022423:Myeloid Cells / Q000378:metabolism / Q000473:pathology*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction
D018941:Antigens, CD19; D016895:Culture Media, Serum-Free; D015850:Interleukin-6; D012333:RNA, Messenger