Comparison of macrophage phenotype between decidua basalis and decidua parietalis by flow cytometry.

The two regions of the maternal decidua, decidua basalis and decidua parietalis, differ in the extent of trophoblast invasion and consequently in cytokines and other biological mediators, extracellular matrix and cellular components. Our aim was to compare the phenotypic features of macrophages from the two decidual regions across a broad gestational age range. We isolated macrophages by enzymatic digestion from healthy decidua samples obtained after elective abortions, at 9-18-week and at 19-23-weeks, or after term deliveries (caesarean sections at term and spontaneous term vaginal deliveries). Macrophages were analysed by flow cytometry applying the same instrument settings to all the samples to allow semi-quantitative comparison of the expression of a particular marker between different samples. We found higher expressions of CD80, CD86 and HLA-DR, suggestive of a more activated phenotype of decidual macrophages, at early/mid pregnancy than at term. Marginal differences were found between term decidual macrophages obtained after spontaneous vaginal deliveries or caesarean sections which imply that the parturient process is not associated with decidual macrophage activation. The expressions of CD105, DC-SIGN and MMR were the strongest in decidua basalis of mid pregnancy and indicate the importance of decidual macrophages in tissue homeostasis at the uteroplacental interface.

Siramesine triggers cell death through destabilisation of mitochondria, but not lysosomes.

A sigma-2 receptor agonist siramesine has been shown to trigger cell death of cancer cells and to exhibit a potent anticancer activity in vivo. However, its mechanism of action is still poorly understood. We show that siramesine can induce rapid cell death in a number of cell lines at concentrations above 20 µM. In HaCaT cells, cell death was accompanied by caspase activation, rapid loss of mitochondrial membrane potential (MMP), cytochrome c release, cardiolipin peroxidation and typical apoptotic morphology, whereas in U-87MG cells most apoptotic hallmarks were not notable, although MMP was rapidly lost. In contrast to the rapid loss of MMP above 20 µM siramesine, a rapid increase in lysosomal pH was observed at all concentrations tested (5-40 µM); however, it was not accompanied by lysosomal membrane permeabilisation (LMP) and the release of lysosomal enzymes into the cytosol. Increased lysosomal pH reduced the lysosomal degradation potential as indicated by the accumulation of immature forms of cysteine cathepsins. The lipophilic antioxidant α-tocopherol, but not the hydrophilic antioxidant N-acetyl-cysteine, considerably reduced cell death and destabilisation of mitochondrial membranes, but did not prevent the increase in lysosomal pH. At concentrations below 15 µM, siramesine triggered cell death after 2 days or later, which seems to be associated with a general metabolic and energy imbalance due to defects in the endocytic pathway, intracellular trafficking and energy production, and not by a specific molecular event. Overall, we show that cell death in siramesine-treated cells is induced by destabilisation of mitochondria and is independent of LMP and the release of cathepsins into the cytosol. Moreover, it is unlikely that siramesine acts exclusively through sigma-2 receptors, but rather through multiple molecular targets inside the cell. Our findings are therefore of significant importance in designing the next generation of siramesine analogues with high anticancer potential.

Changes in Th1/Th2 cytokine balance in Graves' disease.

Graves' disease (GD) is characterised by hyperthyroidism, caused by stimulatory thyrotropin receptor (TSHR) antibodies. Recent research shows that an important factor in the pathogenesis of autoimmune diseases is the change in the balance between Th1 cytokines, which promote cell mediated immunity, and Th2 cytokines, which promote humoral immunity. There are contradictory data about this balance shift in GD. Our objective was to determine the Th1/Th2 cytokine balance shift in patients with newly diagnosed GD, when compared to the same balance in healthy controls. We isolated mononuclear cells (MNC) from the peripheral blood of healthy donors and from patients with newly diagnosed GD before treatment. The MNC were activated with ionomycin in combination with phorbol 12-myristate 13-acetate (PMA). After 40-hour incubation, the concentrations of the cytokines produced (IFN-gamma, IL-4, IL-10, IL-12) in the culture supernatants were measured by ELISA (Endogen, USA). The MNC cultures from patients with GD produced significantly less IL-12 and significantly more IL-10 and IL-4 than MNC cultures from healthy controls. All calculated ratios of Th1 against Th2 cytokines in MNC cultures from patients with GD were significantly lower than in MNC cultures from healthy controls. Our results show a systemic shift of cytokine production in patients with GD toward the Th2 cytokine response, thus confirming the key role of TSHR antibodies and humoral immunity in the pathogenesis of GD.