Fig. 4

Role of SOCS3 and TLR2 in mediating LIF inhibition. a-b LIF induction of SOCS3 is associated with a reduction in MOG expression (shown in Fig. 1). Cells cultured for 1 day in GM were switched to DM; after 3 h they were treated with the indicated concentrations of LIF (a), or with or without EPO (10 ng/ml) and LIF (10 ng/ml; b). After 1 h, SOCS3 mRNA was measured by RT-qPCR. Results, expressed as fold change (FC) vs one of the control (ctr) samples (no LIF in a) are the mean ± SD of quadruplicate samples assayed in duplicate and are representative of two independent experiments; * P < 0.05, ***P < 0.001 vs control (no LIF); § P < 0.001 vs EPO by two-tailed Student’s t-test. c OSM and CNTF inhibit EPO-induced MOG expression. Cells cultured as above were treated with or without EPO (10 ng/ml) and OSM or CNTF (both at 6.5 ng/ml, equimolar concentrations to LIF 10 ng/ml). MOG gene expression was measured by RT-qPCR at day 3. Results, expressed as above, are the mean ± SD of eight samples from two independent experiments assayed in duplicate; *** P < 0.001 vs EPO alone; § P < 0.001 vs untreated by two-tailed Student’s t-test. d TLR2 engagement inhibits EPO-induced MOG expression. Cells were differentiated in the absence or in the presence of EPO (10 ng/ml), with or without LIF (10 ng/ml) or Pam3 (1 μg/ml), a TLR2/1 ligand. MOG expression was measured at day 3 by RT-qPCR. Results, expressed as above, are the mean ± SD of quadruplicate samples assayed in duplicate and are representative of two independent experiments; ***P < 0.001 vs EPO alone; § P < 0.01 vs EPO + LIF by two-tailed Student’s t-test