Inflammation mediated by the peripheral infiltration of inflammatory cells plays an important role in intracerebral hemorrhage (ICH) induced secondary injury. Previous studies have indicated that regulatory T lymphocytes (Tregs) might reduce ICH-induced inflammation, but the precise mechanisms that contribute to ICH-induced inflammatory injury remain unclear. Our results show that the number of Tregs in the brain increases after ICH. Inducing Tregs deletion using a CD25 antibody or Foxp3 DTR -mice increased neurological deficient scores (NDS), the level of inflammatory factors, hematoma volumes, and neuronal degeneration. Meanwhile, boosting Tregs using a CD28 super-agonist antibody reduced the inflammatory injury. Furthermore, Tregs depletion shifted microglia/macrophage polarization toward the M1 phenotype while boosting Tregs shifted this transition toward the M2 phenotype. In vitro, a transwell co-culture model of microglia and Tregs indicated that Tregs changed the polarization of microglia, decreased the expression of MHC-II, IL-6, and TNF-a and increased CD206 expression. IL-10 originating from Tregs mediated the microglia polarization by increasing the expression of Glycogen Synthase Kinase 3 beta (GSK3b), which phosphorylates and inactivates Phosphatase and Tensin homologue (PTEN) in microglia, TGF-b did not participate in this conversion. Thus, Tregs ameliorated ICH-induced inflammatory injury by modulating microglia/macrophage polarization toward the M2 phenotype through the IL-10/GSK3b/PTEN axis.

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ABSTRACTHelicobacter pyloriinfection is thought to be involved in the development of several gastric diseases. TwoH. pylorivirulence factors (vacuolating cytotoxin A and cytotoxin-associated gene A) reportedly interact with lipid rafts in gastric epithelial cells. The role of Toll-like receptor (TLR)-mediated signaling in response toH. pyloriinfection has been investigated extensively in host cells. However, the receptor molecules in lipid rafts that are involved inH. pylori-induced innate sensing have not been well characterized. This study investigated whether lipid rafts play a role inH. pylori-induced ceramide secretion and TLR4 expression and thereby contribute to inflammation in gastric epithelial cells. We observed that both TLR4 and MD-2 mRNA and protein levels were significantly higher inH. pylori-infected AGS cells than in mock-infected cells. Moreover, significantly more TLR4 protein was detected in detergent-resistant membranes extracted fromH. pylori-infected AGS cells than in those extracted from mock-infected cells. However, this effect was attenuated by the treatment of cells with cholesterol-usurping agents, suggesting thatH. pylori-induced TLR4 signaling is dependent on cholesterol-rich microdomains. Similarly, the level of cellular ceramide was elevated and ceramide was translocated into lipid rafts afterH. pyloriinfection, leading to interleukin-8 (IL-8) production. Using the sphingomyelinase inhibitor imipramine, we observed thatH. pylori-induced TLR4 expression was ceramide dependent. These results indicate the mobilization of ceramide and TLR4 into lipid rafts byH. pyloriinfection in response to inflammation in gastric epithelial cells.

Upon infection of the gastric epithelial cells, the Helicobacter pylori cytotoxin-associated gene A (CagA) virulence protein is injected into the epithelial cells via the type IV secretion system (TFSS), which is dependent on cholesterol. Translocated CagA is targeted by the membrane-recruited c-Src family kinases in which a tyrosine residue in the Glu-Pro-Ile-Tyr-Ala (EPIYA)-repeat region, which can be phosphorylated, induces cellular responses, including interleukin-8 (IL-8) secretion and hummingbird phenotype formation. In this study, we explored the role of EPIYA-containing C-terminal domain (CTD) in CagA tethering to the membrane lipid rafts and in IL-8 activity. We found that disruption of the lipid rafts reduced the level of CagA translocation/phosphorylation as well as CagA-mediated IL-8 secretion. By CagA truncated mutagenesis, we identified that the CTD, rather than the N-terminal domain, was responsible for CagA tethering to the plasma membrane and association with detergent-resistant membranes, leading to CagA-induced IL-8 promoter activity. Our results suggest that CagA CTD-containing EPIYAs directly interact with cholesterol-rich microdomains that induce efficient IL-8 secretion in the epithelial cells.

Lennox-Gastaut syndrome (LGS) is a devastating and refractory generalized epilepsy affecting children and adolescents. In this study we report the results of resective surgery in 18 patients with LGS phenotype who underwent single-lobe/lesionectomy or multilobe resection plus multiple subpial transection and/or callosotomy. After surgery, seven patients became completely seizure-free (Engel Class I) and five almost seizure-free (Engel Class II). Additional four had significant seizure control (Engel Class III), and two had no change in seizure frequency (Engel Class IV). Of the 4 patients without any lesion on brain MRI, 2 ended with Engel Class II, 1 with III and the other with IV in Engels' classification. Mean intelligence quotient (IQ) increased from 56.1 ± 8.1 (mean ± SD) before operation to 67.4 ± 8.2 (mean ± SD) after operation, a significant improvement (P = 0.001). Results also indicated that the younger the patient at surgery, or the shorter the interval between onset of seizure and resective operation, the better the intellectual outcome. Our data suggest that resective epilepsy surgery can be successful in patients with LGS phenotype as long as the EEG shows dominance of discharges in one hemisphere and corresponding ipsilateral imaging findings, even with contralateral ictal discharges.