Expression of leukemia inhibitory factor and its receptors is increased during differentiation of human embryonic stem cells.
OBJECTIVE
To investigate gene expression profiles during the early spontaneous differentiation of human embryonic stem cells (hESCs), with particular emphasis on leukemia inhibitory factor (LIF)-induced pathways and the ultrastructural surface morphology of the undifferentiated and spontaneously differentiated hESCs.


METHODS
Prospective experimental study.


METHODS
University laboratory.


METHODS
Four hESC cell lines.


METHODS
The effect of LIF on receptor expression level was studied in cultures.


METHODS
Gene expression in the hESC line HS237 was analyzed using microarrays. Real-time reverse-transcription polymerase chain reaction was used to validate the microarray results in four hESC lines (HS181, HS235, HS237, HS293). Immunohistochemistry was used to assay LIF, LIF receptor, and gp130 protein expression. Cell surface morphology was studied using scanning electron microscopy.


RESULTS
The expression of LIF, LIF receptor, and gp130 messenger RNA and protein was increased in spontaneously differentiated HS237 cells compared with undifferentiated cells, with high expression of an inhibitor of LIF-mediated signaling, suppressor of cytokine signaling-1, in undifferentiated hESCs. Genes, those expressed specifically and those shared in undifferentiated hESCs, differentiated cells, and in fibroblasts, were identified. Supplementation with LIF did not affect the LIF receptor expression.


CONCLUSIONS
The expression of LIF and its receptors is low in undifferentiated hESCs but increases during differentiation. Added LIF does not prevent spontaneous differentiation. Suppressor of cytokine signaling-1 may prevent LIF signaling in hESCs.
Aghajanova
Lusine
L
Department of Obstetrics and Gynecology, CLINTEC, Karolinska Institute, Karolinska University Hospital Huddinge, Stockholm, Sweden. lusine.aghajanova@klinvet.ki.se
Skottman
Heli
H
Strömberg
Anne-Marie
AM
Inzunza
José
J
Lahesmaa
Riitta
R
Hovatta
Outi
O
D002454:Cell Differentiation / Q000502:physiology*; D002478:Cells, Cultured; D004622:Embryo, Mammalian / Q000166:cytology*; D005347:Fibroblasts / Q000378:metabolism; D020869:Gene Expression Profiling; D006023:Glycoproteins / Q000235:genetics / Q000378:metabolism; D006801:Humans; D015850:Interleukin-6 / Q000235:genetics / Q000378:metabolism*; D053605:Leukemia Inhibitory Factor; D053680:Leukemia Inhibitory Factor Receptor alpha Subunit; D008855:Microscopy, Electron, Scanning; D012333:RNA, Messenger / Q000378:metabolism; D018121:Receptors, Cytokine / Q000235:genetics / Q000378:metabolism*; D053606:Receptors, OSM-LIF; D015398:Signal Transduction; D013234:Stem Cells / Q000166:cytology* / Q000378:metabolism / Q000648:ultrastructure; D000071222:Suppressor of Cytokine Signaling 1 Protein; D050826:Suppressor of Cytokine Signaling Proteins / Q000378:metabolism
D006023:Glycoproteins; D015850:Interleukin-6; C507837:LIF protein, human; C507840:LIFR protein, human; D053605:Leukemia Inhibitory Factor; D053680:Leukemia Inhibitory Factor Receptor alpha Subunit; D012333:RNA, Messenger; D018121:Receptors, Cytokine; D053606:Receptors, OSM-LIF; C108944:SOCS1 protein, human; D000071222:Suppressor of Cytokine Signaling 1 Protein; D050826:Suppressor of Cytokine Signaling Proteins; C480482:glycoprotein 130, human