TASK DEFINITION: In this task, you are given a passage which has a question and the context. You have to generate an answer to the question based on the information present in the context.
PROBLEM: Context: Allogeneic mesenchymal stem cells (MSCs) exhibit therapeutic effects in human autoimmune diseases such as systemic lupus erythematosus (SLE), but the underlying mechanisms remain largely unknown. The aim of this study was to investigate how allogeneic MSCs mediate immunosuppression in lupus patients.', 'The effects of allogeneic umbilical cord-derived MSCs (UC-MSCs) on inhibition of T cell proliferation were determined. MSC functional molecules were stimulated with peripheral blood mononuclear cells from healthy controls and SLE patients and examined by real-time polymerase chain reaction. CD4+ and CD8+ T cells were purified using microbeads to stimulate MSCs in order to determine cytokine expression by MSCs and to further determine which cell subset(s) or which molecule(s) is involved in inhibition of MSC-mediated T cell proliferation. The related signaling pathways were assessed. We determined levels of serum cytokines in lupus patients before and after UC-MSC transplantation.', 'Allogeneic UC-MSCs suppressed T cell proliferation in lupus patients by secreting large amounts of indoleamine 2,3-dioxygenase (IDO). We further found that interferon- (IFN), which is produced predominantly by lupus CD8+ T cells, is the key factor that enhances IDO activity in allogeneic MSCs and that it is associated with IFNGR1/JAK-2/STAT signaling pathways. Intriguingly, bone marrow-derived MSCs from patients with active lupus demonstrated defective IDO production in response to IFN and allogeneic CD8+ T cell stimulation. After allogeneic UC-MSC transplantation, serum IDO activity increased in lupus patients.\Question: Is a CD8 T cell/indoleamine 2,3-dioxygenase axis required for mesenchymal stem cell suppression of human systemic lupus erythematosus?

SOLUTION: We found a previously unrecognized CD8+ T cell/IFN/IDO axis that mediates the therapeutic effects of allogeneic MSCs in lupus patients.

PROBLEM: Context: Stem cell factor (SCF) has well-known proliferative effects on hematopoietic cells. SCF also has effects on differentiation and proliferation in other cell types. Interleukin-6 (IL-6) and tumor necrosis factor (TNF)-alpha have proliferative effects in the liver. Recent studies in our laboratory have linked SCF's hepatoproliferative actions to those of IL-6, demonstrating that IL-6-induced hepatocyte proliferation depends, at least in part, on SCF. We now hypothesize that TNF-alpha's hepatoproliferative effects are also dependent on SCF.", 'In vitro studies using primary mouse hepatocytes show that SCF is induced by TNF-alpha; anti-SCF antibody treatment in this system inhibits TNF-alpha-induced hepatocyte proliferation, suggesting that TNF-alpha-induced hepatocyte proliferation is also SCF dependent. Additional in vivo experiments were performed in which wild type and/or TNF-alpha receptor-1 knockout mice (TNFR1(-/-)) were subjected to 70% hepatectomy or sham laparotomy. TNFR1(-/-) mice are known to have delayed hepatic regeneration after partial hepatectomy. Initial experiments demonstrated that the SCF receptor, c-kit, is upregulated after partial hepatectomy in wild-type mice, further emphasizing the importance of this system in the restoration of hepatic mass. SCF administration to TNFR1(-/-) mice in the context of partial hepatectomy restores hepatocyte proliferation to normal. Further, SCF administration to TNFR1(-/-) mice before hepatectomy increases phosphotyrosine signal transducer and activator (p-stat-3) levels, suggesting that SCF-induced increases in hepatocyte proliferation may also be stat-3 mediated.\Question: Are stem cell factor and its receptor , c-kit , important for hepatocyte proliferation in wild-type and tumor necrosis factor receptor-1 knockout mice after 70 % hepatectomy?

SOLUTION: These data suggest that TNF-alpha-induced hepatocyte proliferation depends, at least in part, on SCF and that SCF and its receptor, c-kit, are important for the liver's regenerative processes.

PROBLEM: Context: The Wada test is a diagnostic method to anesthetize 1 cerebral hemisphere and assess the language and memory functions of awake contralateral hemisphere before temporal lobectomy in patients with epilepsy. The effects of an ipsilateral injection of etomidate on the functional properties of contralateral hemisphere are not known. Our aim was to characterize the electroencephalographic (EEG) effects after intracarotid injection of etomidate and to determine the changes in synchronization between the ipsilateral and contralateral hemispheres.', 'We retrospectively analyzed EEG data from 15 patients who underwent Wada test with etomidate. Continuous EEG data from 4 electrodes (2 anterior [F3, F4] and 2 posterior [P3, P4]) were analyzed. After artifact rejection, we measured the amplitudes of delta (1 to 4 Hz) and alpha (7 to 13 Hz) waves and the changes in the interhemispheric synchronization before, during, and after etomidate injection.', 'Ipsilateral injection of etomidate causes EEG changes in both hemispheres with increased amplitude of delta waves anteriorly and the alpha waves posteriorly. However this effect of etomidate is not uniform. Although there was a decrease in the interhemispheric synchronization of delta waves, there was no change in the synchronization of the alpha waves.\Question: Does intracarotid Etomidate decrease the Interhemispheric Synchronization in Electroencephalogram ( EEG ) During the Wada Test?

SOLUTION:
Our study showed that the EEG effects of intracarotid ipsilateral injection of etomidate is not uniform in both hemispheres. Decrease in the interhemispheric synchronization of delta waves might serve as an indicator of ipsilateral effect of etomidate on the brain. Additional studies are needed to confirm our findings.