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-γ (IFNγ), 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 IFNγ 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/IFNγ/IDO axis that mediates the therapeutic effects of allogeneic MSCs in lupus patients.

PROBLEM: Context: To describe the findings of enhanced depth imaging (EDI) optical coherence tomography (OCT) of the lamina cribrosa (LC) in glaucoma and pachychoroid spectrum diseases associated with peripapillary retinoschisis.', 'Retrospective, observational case series.', 'A total of 16 patients from 1 institution.', 'Detailed medical case histories, optic disc and retinal imaging with EDI using the Spectralis OCT (Heidelberg Engineering, Heidelberg, Germany), and clinical course were reviewed for patients with peripapillary retinoschisis without a known predisposing condition.', 'Clinical features and findings of the EDI OCT.', 'Among the 16 eyes with peripapillary retinoschisis that had abnormal findings on EDI of the LC, 8 had glaucoma and 8 had pachychoroid spectrum diseases, including chronic central serous chorioretinopathy (CSC) (6 eyes), small pigment epithelium detachment (1 eye), and polypoidal choroidal vasculopathy (PCV) (1 eye). The abnormal LC findings were central or peripheral focal LC defects in eyes with glaucoma and LC disinsertions or peripheral focal LC defects in eyes with pachychoroid spectrum diseases. Central LC defects were related to inner layer retinoschisis, whereas LC disinsertions and peripheral LC defects were related to outer layer retinoschisis. The peripapillary retinoschisis did not show a topographic association with the underlying chronic CSC- or PCV-associated lesions. In 6 treated eyes with pachychoroid, peripapillary retinoschisis resolved along with subretinal fluid after anti-vascular endothelial growth factor injection in 4 eyes, whereas retinoschisis persisted after the resolution of subretinal fluid in 2 eyes.\Question: Do alterations of the Lamina Cribrosa Are Associated with Peripapillary Retinoschisis in Glaucoma and Pachychoroid Spectrum Disease?

SOLUTION: Enhanced depth imaging OCT of the LC demonstrated alterations associated with peripapillary retinoschisis, pachychoroid spectrum diseases, and glaucoma.

PROBLEM: Context: Insulin resistance is a major risk factor for type 2 diabetes in women with polycystic ovary syndrome (PCOS). The molecular mechanisms underlying reduced insulin-mediated glycogen synthesis in skeletal muscle of patients with PCOS have not been established.', 'We investigated protein content, activity, and phosphorylation of glycogen synthase (GS) and its major upstream inhibitor, GS kinase (GSK)-3 in skeletal muscle biopsies from 24 PCOS patients (before treatment) and 14 matched control subjects and 10 PCOS patients after 16 wk treatment with pioglitazone. All were metabolically characterized by euglycemic-hyperinsulinemic clamps and indirect calorimetry.', 'Reduced insulin-mediated glucose disposal (P < 0.05) was associated with a lower insulin-stimulated GS activity in PCOS patients (P < 0.05), compared with controls. This was, in part, explained by absent insulin-mediated dephosphorylation of GS at the NH2-terminal sites 2+2a, whereas dephosphorylation at the COOH-terminal sites 3a+3b was intact in PCOS subjects (P < 0.05). Consistently, multiple linear regression analysis showed that insulin activation of GS was dependent on dephosphorylation of sites 3a+3b in women with PCOS. No significant abnormalities in GSK-3alpha or -3beta were found in PCOS subjects. Pioglitazone treatment improved insulin-stimulated glucose metabolism and GS activity in PCOS (all P < 0.05) and restored the ability of insulin to dephosphorylate GS at sites 2 and 2a.\Question: Is impaired insulin activation and dephosphorylation of glycogen synthase in skeletal muscle of women with polycystic ovary syndrome reversed by pioglitazone treatment?

SOLUTION:
Impaired insulin activation of GS including absent dephosphorylation at sites 2+2a contributes to insulin resistance in skeletal muscle in PCOS. The ability of pioglitazone to enhance insulin sensitivity, in part, involves improved insulin action on GS activity and dephosphorylation at NH2-terminal sites.