Mage program (developed at the U.S. National Institutes of Health and available on the internet at http://rsb.info.nih.gov/ nih-image/).RNA extraction and TaqMan real-time RT-PCRTotal RNA was isolated with TRIzol Reagent (Invitrogen Corp, Carlsbad, CA) and RNeasy Kit (Qiagen Inc., Valencia, CA) according to the manufacture’s protocol. Primers used for realtime reverse-transcription polymerase chain reaction (real-time RT-PCR) include IL-6, LIF, Ciliary neurotrophic factor (CNTF) and Glyceraldehyde 3-phosphate dehydrogenase (GAPDH, part # 4310884E, Applied Biosystems Inc). Real-time RT-PCR was carried 22948146 out using the one-step quantitative TaqMan assay in a StepOneTM Real-Time PCR system (Applied Biosystems Inc.). Relative IL-6, LIF, and CNTF mRNA levels were determined and standardized with a GAPDH internal control using comparative DDCT method. All primers used in the study were tested for amplification efficiencies and the results were similar.Human neural progenitor cell differentiationNeuronal differentiation of NPCs was performed as Methionine enkephalin previously described [19]. Briefly, dissociated NPCs were plated on poly-Dlysine-coated cell culture dishes in NPIM for 24 h. Cells were subsequently changed to serum-free Neurobasal medium (Gibco BRL) supplemented with B27 (NB27 medium) (Gibco BRL) with or without TNF-a. For the inhibition of releasing factors in response of TNF-a treatment, cells were pre-incubated with neutralizing antibodies 
for LIF or IL-6 
for 1 h at 37uC and then treated with TNF-a. Cells were 1662274 collected for protein, or fixed for immunocytochemical staining 6 days after TNF-a treatment.Enzyme-linked immunosorbent assay (ELISA)Supernatants were collected for IL-6 and LIF determination by an in house ELISA. Briefly, 96-well micro titer plates (Costar) were coated overnight at room temperature with capture antibodies (R D Systems) in PBS. Non-specific Tubastatin A binding was blocked for 2 h with 1 BSA in PBS. Triplicate samples of cell supernatants or a serial dilution of standards of human recombinant IL-6 or LIF were applied to the wells and incubated overnight at 4uC. Samples were removed and wells were incubated with the biotinylated detection antibodies, followed by 1 h incubation with HRPconjugated streptavidin (R D Systems). TMB Substrate Solution (Sigma) was added and the absorbance was determined using a microplate reader (Rio-Rad Laboratories, Hercules, CA) set at 450 nm.ImmunocytochemistryCells were fixed in 4 PFA and washed in PBS as previously described [19]. Cells were then incubated overnight with primary antibodies, followed by Alexa Fluor secondary antibodies, goat anti-mouse IgG Alexa Fluor 488 and goat anti-rabbit IgG Alexa Fluor 594 (Molecular Probes, Eugene, OR, 1:800) for 1 h at room temperature. Primary antibodies included mouse anti-b-IIItubulin (Sigma-Aldrich, 1:400), rabbit anti-GFAP (glial fibrillary acidic protein, Dako, Carpinteria, CA, 1:1000), mouse anti-nestin (Chemicon, 1:600), rabbit anti-phospho STAT3 (P-STAT3, Cell Signaling Technologies, 1:1000), and mouse anti-LIF (R D Systems, 1:400). All antibodies were diluted in 0.1 Triton X-100, 2 BSA in PBS. Cells were counterstained with DAPI (SigmaStatistical analysesData were presented as means 6 standard deviation (SD) unless otherwise noted. All experiments were repeated at least three timesTNF-a Induces Astrogliogenesis via LIFwith different donors with triplicate or quadruplicate samples in each assay. All data were evaluated statistically by the analysis of v.Mage program (developed at the U.S. National Institutes of Health and available on the internet at http://rsb.info.nih.gov/ nih-image/).RNA extraction and TaqMan real-time RT-PCRTotal RNA was isolated with TRIzol Reagent (Invitrogen Corp, Carlsbad, CA) and RNeasy Kit (Qiagen Inc., Valencia, CA) according to the manufacture’s protocol. Primers used for realtime reverse-transcription polymerase chain reaction (real-time RT-PCR) include IL-6, LIF, Ciliary neurotrophic factor (CNTF) and Glyceraldehyde 3-phosphate dehydrogenase (GAPDH, part # 4310884E, Applied Biosystems Inc). Real-time RT-PCR was carried 22948146 out using the one-step quantitative TaqMan assay in a StepOneTM Real-Time PCR system (Applied Biosystems Inc.). Relative IL-6, LIF, and CNTF mRNA levels were determined and standardized with a GAPDH internal control using comparative DDCT method. All primers used in the study were tested for amplification efficiencies and the results were similar.Human neural progenitor cell differentiationNeuronal differentiation of NPCs was performed as previously described [19]. Briefly, dissociated NPCs were plated on poly-Dlysine-coated cell culture dishes in NPIM for 24 h. Cells were subsequently changed to serum-free Neurobasal medium (Gibco BRL) supplemented with B27 (NB27 medium) (Gibco BRL) with or without TNF-a. For the inhibition of releasing factors in response of TNF-a treatment, cells were pre-incubated with neutralizing antibodies for LIF or IL-6 for 1 h at 37uC and then treated with TNF-a. Cells were 1662274 collected for protein, or fixed for immunocytochemical staining 6 days after TNF-a treatment.Enzyme-linked immunosorbent assay (ELISA)Supernatants were collected for IL-6 and LIF determination by an in house ELISA. Briefly, 96-well micro titer plates (Costar) were coated overnight at room temperature with capture antibodies (R D Systems) in PBS. Non-specific binding was blocked for 2 h with 1 BSA in PBS. Triplicate samples of cell supernatants or a serial dilution of standards of human recombinant IL-6 or LIF were applied to the wells and incubated overnight at 4uC. Samples were removed and wells were incubated with the biotinylated detection antibodies, followed by 1 h incubation with HRPconjugated streptavidin (R D Systems). TMB Substrate Solution (Sigma) was added and the absorbance was determined using a microplate reader (Rio-Rad Laboratories, Hercules, CA) set at 450 nm.ImmunocytochemistryCells were fixed in 4 PFA and washed in PBS as previously described [19]. Cells were then incubated overnight with primary antibodies, followed by Alexa Fluor secondary antibodies, goat anti-mouse IgG Alexa Fluor 488 and goat anti-rabbit IgG Alexa Fluor 594 (Molecular Probes, Eugene, OR, 1:800) for 1 h at room temperature. Primary antibodies included mouse anti-b-IIItubulin (Sigma-Aldrich, 1:400), rabbit anti-GFAP (glial fibrillary acidic protein, Dako, Carpinteria, CA, 1:1000), mouse anti-nestin (Chemicon, 1:600), rabbit anti-phospho STAT3 (P-STAT3, Cell Signaling Technologies, 1:1000), and mouse anti-LIF (R D Systems, 1:400). All antibodies were diluted in 0.1 Triton X-100, 2 BSA in PBS. Cells were counterstained with DAPI (SigmaStatistical analysesData were presented as means 6 standard deviation (SD) unless otherwise noted. All experiments were repeated at least three timesTNF-a Induces Astrogliogenesis via LIFwith different donors with triplicate or quadruplicate samples in each assay. All data were evaluated statistically by the analysis of v.