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The CD40/CD40L system is a binding key for co-stimulation of immune cells. Soluble form of CD40L has been widely studied as marker of inflammatory and autoimmune diseases. Here we analyze serum concentrations of sCD40L, as well as 14 cytokines, in patients with Multiple Sclerosis (MS) treated with Glatiramer acetate or Interferon beta. In the healthy control group, we found in serum a highly positive correlation between sCD40L and Interleukin (IL)-31, an anti-inflammatory Th2 cytokine. Additionally, an important reduction in IL-31 and sCD40L serum levels, as well as a significant reduction in CD40 mRNA expression and complete depletion of CD40L mRNA, detected from peripheral blood cells, was found in treated patients with MS. Therefore, sCD40L and IL-31 must be taken into account as possible prognostic markers when analyzing the disease progress of MS in order to provide more personalized treatment.  相似文献   
66.

Objective

N6-isopentenyladenosine (iPA) is an intermediate of the mevalonate pathway that exhibits various anti-cancer effects. However, studies on its anti-inflammatory activity are scarce and underlying molecular mechanisms are unknown. Therefore, we aimed to investigate the ability of iPA to exert anti-inflammatory effects in the human cystic fibrosis (CF) cell model of exacerbated inflammation.

Materials and methods

TNFα-stimulated CF cells CuFi-1 and its normal counterpart NuLi-1 were pre-treated with increasing concentrations of iPA and cell viability and proliferation were assessed by MTT and BrdU assays. The effect of iPA on IL-8 and RANTES secretion was determined by ELISA, and the activation and expression of signaling molecules and selenoproteins were studied by Western blot. To assess the direct effect of iPA on NFκB activity, luciferase assay was performed on TNFα-stimulated HEK293/T cells transfected with a NFκB reporter plasmid.

Results

We demonstrated for the first time that iPA prevents IL-8 and RANTES release in TNFα-stimulated CF cells and this effect is mediated by increasing the expression of the direct NFκB inhibitor IκBα and decreasing the levels of STAT3. Consistent with this, we showed that iPA inhibited TNFα-mediated NFκB activation in HEK/293T cells. Finally, we also found that iPA improved the levels of glutathione peroxidase 1 and thioredoxin reductase 1 only in CF cells suggesting its ability to maintain sufficient expression of these anti-oxidant selenoproteins.

Conclusions

Our findings indicate that iPA can exert anti-inflammatory activity especially in the cases of excessive inflammatory response as in CF.
  相似文献   
67.
Parasitology Research - Amphibians are hosts for a wide variety of micro- and macro-parasites. Chigger mites from the Hannemania genus are known to infect a wide variety of amphibian species across...  相似文献   
68.

Background

Over-activated microglia play a central role during neuroinflammation, leading to neuronal cell death and neurodegeneration. Reversion of over-activated to neuroprotective microglia phenotype could regenerate a healthy CNS-supporting microglia environment. Our aim was to identify a dataset of intracellular molecules in primary microglia that play a role in the transition of microglia to a ramified, neuroprotective phenotype.

Methods

We exploited the anti-inflammatory and neuroprotective properties of conditioned medium of adipose-derived mesenchymal stem cells (CM) as a tool to generate the neuroprotective phenotype of microglia in vitro, and we set up a microscopy-based siRNA screen to identify its hits by cell morphology.

Results

We initially assayed an array of 157 siRNAs against genes that codify proteins and factors of cytoskeleton and activation/inflammatory pathways in microglia. From them, 45 siRNAs significantly inhibited the CM-induced transition from a neurotoxic to a neuroprotective phenotype of microglia, and 50 siRNAs had the opposite effect. As a proof-of-concept, ten of these targets were validated with individual siRNAs and by downregulation of protein expression. This validation step resulted essential, because three of the potential targets were false positives. The seven validated targets were assayed in a functional screen that revealed that the atypical RhoGTPase RhoE/Rnd3 is necessary for BDNF expression and plays an essential role in controlling microglial migration.

Conclusions

Besides the identification of RhoE/Rnd3 as a novel inducer of a potential neuroprotective phenotype in microglia, we propose a list of potential targets to be further confirmed with selective activators or inhibitors.
  相似文献   
69.
Chronic graft-versus-host disease (cGVHD) is a major complication after stem cell transplantation (HSCT). Several randomized studies already demonstrated that anti-T lymphoglobulin (ATLG) is effective in preventing GVHD after myeloablative unrelated and HLA-identical sibling transplants. However, the issue of doses and the potential increase of relapses still remain unsolved. Here we report data on 190 patients with acute leukemia and myelodysplastic syndrome who underwent an unrelated HSCT with low-dose ATLG (15 to 30 mg/kg) given at an earlier timing (days –6 to –2). HSCT was performed from HLA 10/10 (n?=?62, 33%), 9/10 (n?=?91, 48%), 8/10 (n?=?30, 16%), and <8/10 (n?=?7, 4%) identical unrelated donor. Peripheral blood was the stem cell source in 42% (n?=?80). Median follow-up was 51 months. Grades II to IV and III to IV acute GVHD were 26% and 9%, respectively, and 2-year overall and moderate to severe cGVHD were 23% and 14%, respectively. The 3-year incidences of relapse and nonrelapse mortality were 26% and 18%, respectively. The rates of 3-year overall survival (OS), disease-free survival (DFS), and GVHD-free and relapse-free survival (GRFS) were 60%, 56% and 44%, respectively. Factors such as younger donor, good performance status, and early disease were associated with better outcome in terms of OS, DFS, and GRFS. Our data indicate that doses of ATLG lower that those used in randomized clinical trials can be used for GVHD prevention, even in the adult setting, without clear increases in relapse and infections; these findings need to be further validated by a prospective randomized study.  相似文献   
70.
Patients with blood-related diseases often cannot identify a matched related donor and must seek donors in unrelated donor registries. These registries face the challenge of ensuring that potential donors are available when contacted. Donor attrition is especially problematic when there is only a single perfectly matched potential donor. One way to improve donor availability might be to present perfectly matched donors (high-priority donors [HPDs]) with more precise information about their match status. This project evaluated the impact of providing such information to HPDs at the National Marrow Donor Program (NMDP)/Be The Match. Objectives were to determine the acceptability of the new messaging to both HPDs and the donor contact representatives (DCRs) who delivered the message, consistency of message delivery, and whether the new messaging was associated with improved donor availability. Mixed methods were used to collect telephone interview data from HPDs, matched samples of non-HPDs, and DCRs. Donor availability data came from NMDP records. Key findings were as follows: (1) the HPD message was acceptable to potential donors and did not seem to produce undue pressure, (2) the message was acceptable to DCRs who became more comfortable and consistent in delivering the message over time, but (3) the new messaging did not significantly increase availability. Despite the lack of evidence for increased availability, there may be ethical benefits and little harm to providing well-matched donors with more information about their degree of matching. Research should examine stronger match status messages and delivery of new messaging to additional highly-matched donor groups.  相似文献   
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