Regulation of Proliferation, Differentiation and Survival by the IL-3/IL-5/GM-CSF Receptor Family

The receptors for the Il-3/IL-5/GM-CSF cytokine family are composed of a heterodimeric com-plex of a cytokine-specific a chain and a common ß chain (ßc). Binding of IL-3/IL-5/GM-CSF to their respective receptors rapidly induces activation of multiple intracellular signalling pathways, including the Ras-Raf-ERK, the JAK/STAT, the phosphatidylinositol 3-kinase PKB, and the JNK/SAPK and p38 signalling pathways. This re-view focuses on recent advancements in understanding how these different signalling pathways are activated by IL-3/IL-5/GM-CSF receptors, and how the individual pathways contribute to the pleiotropic effects of IL-3/IL-5/ GM-CSF on their target cells, including proliferation, differentiation, survival, and effector functions

Signal transducer and activator of transcription-1 localizes to the mitochondria and modulates mitophagy

The signal transducer and activator of transcription (STAT) proteins are latent transcription factors that have been shown to be involved in cell proliferation, development, apoptosis, and autophagy. STAT proteins undergo activation by phosphorylation at tyrosine 701 and serine 727 where they translocate to the nucleus to regulate gene expression. STAT1 has been shown to be involved in promoting apoptotic cell death in response to cardiac ischemia/reperfusion and has recently been shown by our laboratory to be involved in negatively regulating autophagy. These processes are thought to promote cell death and restrict cell survival leading to the generation of an infarct. Here we present data that shows STAT1 localizes to the mitochondria and co-immunoprecipitates with LC3. Furthermore, electron microscopy studies also reveal mitochondria from ex vivo I/R treated hearts of STAT1KO mice contained within a double membrane autophagosome indicating that STAT1 may be involved in negatively regulating mitophagy. This is the first description of STAT1 being localized to the mitochondria and also having a role in mitophagy

Activation of 12-O-Tetradecanoylphorbol-13-acetate Response Element- and Dyad Symmetry Element-dependent Transcription by Interleukin-5 Is Mediated by Jun N-terminal Kinase/Stress-activated Protein Kinase Kinases

Interleukin-5 (IL-5) is one of the major regulators of eosinophilic granulocytes in vivo. IL-5 exerts its pleiotropic effects by binding to the IL-5 receptor, which is composed of an IL-5-specific a chain and a common bc chain shared with the receptors for IL-3 and granulocyte- macrophage colony-stimulating factor. Previous studies have shown that binding of IL-5 to its receptor triggers the activation of multiple signaling cascades, including the Ras/mitogen-activated protein kinase, the phosphatidyl -3`-kinase, and the Janus kinase/signal transducer and activator of transcription pathways. Here we describe that IL-5 activates the serine/threonine protein kinase Jun N-terminal kinase/stress-activated protein kinase (JNK/SAPK) pathway. We show that IL-5 activates TPA response element (TRE)-dependent transcription in transfection experiments. TRE activation by IL-5 is mediated by a region of the bc (577- 581) that is also responsible for activation of JNK/SAPK and for activation of dyad symmetry element (DSE)-dependent transcription. Dominant-negative SAPK or ERK kinase-1 was used to demonstrate that JNK/SAPK activation is necessary for induction of DSE- and TREdependent transcription by IL-5, whereas extracellular signal-regulated kinase 2 was not essential for TRE- and DSE-dependent transcription. By contrast, IL-5-induced activation of the tyrosine kinase Janus kinase 2 seems to be a prerequisite for TRE- and DSE-dependent transcription. Taken together, we show for the first time that IL-5 activates kinases of the JNK/SAPK family, and that this activation is linked to IL-5-induced TRE- and DSE-dependent transcription

In Vitro Evaluation of Spider Silk Meshes as a Potential Biomaterial for Bladder Reconstruction

Reconstruction of the bladder by means of both natural and synthetic materials remains a challenge due to severe adverse effects such as mechanical failure. Here we investigate the application of spider major ampullate gland-derived dragline silk from the Nephila edulis spider, a natural biomaterial with outstanding mechanical properties and a slow degradation rate, as a potential scaffold for bladder reconstruction by studying the cellular response of primary bladder cells to this biomaterial. We demonstrate that spider silk without any additional biological coating supports adhesion and growth of primary human urothelial cells (HUCs), which are multipotent bladder cells able to differentiate into the various epithelial layers of the bladder. HUCs cultured on spider silk did not show significant changes in the expression of various epithelial-to-mesenchymal transition and fibrosis associated genes, and demonstrated only slight reduction in the expression of adhesion and cellular differentiation genes. Furthermore, flow cytometric analysis showed that most of the silk-exposed HUCs maintain an undifferentiated immunophenotype. These results demonstrate that spider silk from the Nephila edulis spider supports adhesion, survival and growth of HUCs without significantly altering their cellular properties making this type of material a suitable candidate for being tested in pre-clinical models for bladder reconstruction

Expression and DNA methylation of TNF, IFNG and FOXP3 in colorectal cancer and their prognostic significance.

BACKGROUND: Colorectal cancer (CRC) progression is associated with suppression of host cell-mediated immunity and local immune escape mechanisms. Our aim was to assess the immune function in terms of expression of TNF, IFNG and FOXP3 in CRC. METHODS: Sixty patients with CRC and 15 matched controls were recruited. TaqMan quantitative PCR and methylation-specific PCR was performed for expression and DNA methylation analysis of TNF, IFNG and FOXP3. Survival analysis was performed over a median follow-up of 48 months. RESULTS: TNF was suppressed in tumour and IFNG was suppressed in peripheral blood mononuclear cells (PBMCs) of patients with CRC. Tumours showed enhanced expression of FOXP3 and was significantly higher when tumour size was >38 mm (median tumour size; P=0.006, Mann-Whitney U-test). Peripheral blood mononuclear cell IFNG was suppressed in recurrent CRC (P=0.01). Methylated TNFpromoter (P=0.003) and TNFexon1 (P=0.001) were associated with significant suppression of TNF in tumours. Methylated FOXP3cpg was associated with significant suppression of FOXP3 in both PBMC (P=0.018) and tumours (P=0.010). Reduced PBMC FOXP3 expression was associated with significantly worse overall survival (HR=8.319, P=0.019). CONCLUSIONS: We have detected changes in the expression of immunomodulatory genes that could act as biomarkers for prognosis and future immunotherapeutic strategies

Investigation of a Mesoporous Silicon Based Ferromagnetic Nanocomposite

A semiconductor/metal nanocomposite is composed of a porosified silicon wafer and embedded ferromagnetic nanostructures. The obtained hybrid system possesses the electronic properties of silicon together with the magnetic properties of the incorporated ferromagnetic metal. On the one hand, a transition metal is electrochemically deposited from a metal salt solution into the nanostructured silicon skeleton, on the other hand magnetic particles of a few nanometres in size, fabricated in solution, are incorporated by immersion. The electrochemically deposited nanostructures can be tuned in size, shape and their spatial distribution by the process parameters, and thus specimens with desired ferromagnetic properties can be fabricated. Using magnetite nanoparticles for infiltration into porous silicon is of interest not only because of the magnetic properties of the composite material due to the possible modification of the ferromagnetic/superparamagnetic transition but also because of the biocompatibility of the system caused by the low toxicity of both materials. Thus, it is a promising candidate for biomedical applications as drug delivery or biomedical targeting

Thermodynamics of Nonstoichiometric Nickel Tellurides. I. Heat Capacity and Thermodynamic Functions of the δ Phase from 5 to 350°K

Heat capacities of the nickel tellurides were measured at compositions NiTe1.1 and NiTe2.0 (near limits of homogeneity of the δ phase) and at one intermediate composition, NiTe1.5, from 5 to 350°K. Heat capacity values and entropy and enthalpy increments are tabulated. No evidence of order‐disorder transitions, or thermal anomalies, or of contributions to the thermal properties from the anisotropy or phonon scattering by the holes in the structure on approaching the composition NiTe2 was observed. Although simple additivity of the heat capacities of the constituent elements failed to represent that of the solution compositions adequately, a Kopp‐Neumann treatment in terms of the limiting compositions of the δ phase gives good agreement with the experimental heat capacity and entropy of NiTe1.5 and hence is useful in interpolating to other intermediate compositions.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/70090/2/JCPSA6-28-3-497-1.pd

Contrast Enhancement in Spinal MR Imaging 633

We evaluated 44 patients with suspected spinal tumors or previous laminectomies with gadolinium-DTPA MR imaging in order to characterize the enhancement in normal, postoperative, and neoplastic intraspinal tissue. Using the signal intensity of CSF as an internal control, we calculated the percentage increase in signal intensity from pre-to postgadolinium studies. Tumors (astrocytoma, ependymoma, schwannoma) enhanced 70-350%; epidural scar, normal epidural venous plexus, and dorsal root ganglion enhanced up to 200%. Contrast enhancement does not per se distinguish neoplastic from normal tissue. Enhancement with gadolinium-DTPA appeared to increase the conspicuousness of intramedullary tumors but not intraosseous metastases. We believe that gadolinium-enhanced MR imaging is a valuable adjunct to routine MR imaging in the evaluation of intraspinal neoplastic processes and may be useful in delineating normal and postoperative structures in the spinal canal. Gadolinium (Gd)-DTPA is under evaluation by the FDA as a contrast medium tor MR imaging of the spine. Enhancement of spinal tumors has been shown previously Materials and Methods Forty-two patients were studied under two different phase Ill protocol s. In one protocol (group 1), 22 patients with suspected spinal tumors were studied. Of the 22 enrolled, 15 had surgical or postmortem verification of the diagnosis. Among these patients there were th ree astrocytomas, three ependymomas, three schwannomas, two metastases , and four cysts not associated with a tumor. One of the 15 patients had previously undergone resection of an ependymoma and was evaluated for a presumed recurrence but has not yet been reoperated . Four of the 22 patients had negative MR studies without anatomic confirmation, and three had positive studies . In a second protocol (group II), 20 patients who had previously undergone laminectomy were studied to investigate possible scar tissue or recurrent disk herniations. Eight patients with MR evidence of epidural scar at one or more levels had surgical confirmation of epidural scar (with or without herniated disk). Measurements of contrast enhancement were made in the 14 tumor tissues in group I, in epidural scar in group II , and in normal tissues in both groups. MR was performed on a 1.5-T cryogenic imager with surface coil s. Each patient had sagittal or axial images with 800/20/2 (TR /TE jexcitations) , then with 2500/25/2 and 2500/ 80/2 plus additional images as needed. Gd-DTPA was injected intravenously in a dose of 0.1 mmjkg body weight. The 800/20 images were then repeated in the same planes with the same number of acquisitions, field of view , and so on. Transmit and receive attenuation were optimized with the system 's automatic tuning software for both pre-and post-Gd-DTPA acquisitions. The signal intensity was measured in reg ions of interest in the images pre-and post-Gd-DTPA. The signal intensity of CSF (which was assumed not to enhanc