Clonal Immune Responses of Mycobacterium-Specific γδ T Cells in Tuberculous and Non-Tuberculous Tissues during M. tuberculosis Infection

BACKGROUND: We previously demonstrated that unvaccinated macaques infected with large-dose M.tuberculosis(Mtb) exhibited delays for pulmonary trafficking of Ag-specific αβ and γδ T effector cells, and developed severe lung tuberculosis(TB) and "secondary" Mtb infection in remote organs such as liver and kidney. Despite delays in lungs, local immunity in remote organs may accumulate since progressive immune activation after pulmonary Mtb infection may allow IFNγ-producing γδ T cells to adequately develop and traffic to lately-infected remote organs. As initial efforts to test this hypothesis, we comparatively examined TCR repertoire/clonality, tissue trafficking and effector function of Vγ2Vδ2 T cells in lung with severe TB and in liver/kidney without apparent TB. METHODOLOGY/PRINCIPAL FINDINGS: We utilized conventional infection-immunity approaches in macaque TB model, and employed our decades-long expertise for TCR repertoire analyses. TCR repertoires in Vγ2Vδ2 T-cell subpopulation were broad during primary Mtb infection as most TCR clones found in lymphoid system, lung, kidney and liver were distinct. Polyclonally-expanded Vγ2Vδ2 T-cell clones from lymphoid tissues appeared to distribute and localize in lung TB granuloms at the endpoint after Mtb infection by aerosol. Interestingly, some TCR clones appeared to be more predominant than others in lymphocytes from liver or kidney without apparent TB lesions. TCR CDR3 spetratyping revealed such clonal dominance, and the clonal dominance of expanded Vγ2Vδ2 T cells in kidney/liver tissues was associated with undetectable or low-level TB burdens. Furthermore, Vγ2Vδ2 T cells from tissue compartments could mount effector function for producing anti-mycobacterium cytokine. CONCLUSION: We were the first to demonstrate clonal immune responses of mycobacterium-specific Vγ2Vδ2 T cells in the lymphoid system, heavily-infected lungs and lately subtly-infected kidneys or livers during primary Mtb infection. While clonally-expanded Vγ2Vδ2 T cells accumulated in lately-infected kidneys/livers without apparent TB lesions, TB burdens or lesions appeared to impact TCR repertoires and tissue trafficking patterns of activated Vγ2Vδ2 T cells

Facile solution-phase synthesis of γ-Mn3O4 hierarchical structures

<p>Abstract</p> <p>Background</p> <p>A lot of effort has been focused on the integration of nanorods/nanowire as building blocks into three-dimensional (3D) complex superstructures. But, the development of simple and effective methods for creating novel assemblies of self-supported patterns of hierarchical architectures to designed materials using a suitable chemical method is important to technology and remains an attractive, but elusive goal.</p> <p>Results</p> <p>The hierarchical structure of Mn₃O₄with radiated spherulitic nanorods was prepared via a simple solution-based coordinated route in the presence of macrocycle polyamine, hexamethyl-1,4,8,11-tetraazacyclotetradeca-4,11-diene (CT) with the assistance of thiourea as an additive.</p> <p>Conclusion</p> <p>This approach opens a new and facile route for the morphogenesis of Mn₃O₄material and it might be extended as a novel synthetic method for the synthesis of other inorganic semiconducting nanomaterials such as metal chalcogenide semiconductors with novel morphology and complex form, since it has been shown that thiourea can be used as an effective additive and the number of such water-soluble macrocyclic polyamines also makes it possible to provide various kinds of ligands for different metals in homogeneous water system.</p

Overexpression of CDC2/CyclinB1 in gliomas, and CDC2 depletion inhibits proliferation of human glioma cells in vitro and in vivo

<p>Abstract</p> <p>Background</p> <p>Gliomas are the most common and aggressive primary brain tumors for which unfortunately no effective treatment modalities exist despite advances in molecular biology as the knowledge base to unravel the extremely complex molecular mechanisms of tumorigenesis is limited. In this study an attempt has been made to understand the molecular pathological basis of tumorigenesis which led to an identification of an oncogene, CDC2, and an epigenetic strategy has been evaluated to control the tumorigensis by downregulating this oncogene.</p> <p>Methods</p> <p>Tissue microarrays were utilized to investigate the expression of genes in a large number of tumor samples and to identify overexpressed genes which could be potentially causing tumorigenesis. Retroviral vectors expressing short hairpin RNAs (shRNAs) targeted against CDC2 were designed and transducted into human glioma cell line ex vivo in order to downregulate the expression of CDC2. Real-Time PCR was used to determine the level of CDC2 mRNA. Western Blotting was used to determine the level of expression of CDC2 protein as measure to quantify down regulation of CDC2 expression along with use of flow cytometry to investigate effect of shRNAs on cell cycles and detection of apoptosis. Following ex vivo study, viral particles containing small interfering RNA for CDC2 were subsequently injected into xenogeneic graft tumor of nude mice and the weight of human glioma xenografts, survival and resulting phenotypic changes of target gene were investigated.</p> <p>Results</p> <p>Human glioma tissue microarrays indicated the positive expression rates of CDC2/CyclinB1 with a positive correlation with pathologic grades (r = 0.982, r = 0.959, respectively). Retroviral vectors expressing short hairpin RNAs (shRNAs) against CDC2 caused efficient deletion of CDC2, cellular G2/M arrest concluding in apoptosis and inhibition of proliferation in human glioma cells U251 and SHG-44 cell lines ex vivo. And the viral particles containing small interfering RNA for CDC2 were subsequently injected into subcutaneous and intracranial xenogeneic graft tuomrs of nude mice. For subcutaneous tumors, injection of CDC2-shRNA retroviruses significantly decreased tumor weight and volume compared with control. Immunohistochemistry indicated that CDC2 are negative and TUNEL are positive in tumors treated with recombinant retrovirus. For mice implanted with intracranial gliomas, treatment of CDC2-shRNA retroviruses increased survival times compared with control.</p> <p>Conclusion</p> <p>CDC2 gene plays an important role in the proliferation of human gliomas. Downregulation of CDC2 could potentialy inhibit human gliomas cells growth ex vivo and in vivo. From these results, it was suggested that CDC2 might be a potential target on gene therapy of human gliomas.</p

MicroRNA Expression Analysis: Clinical Advantage of Propranolol Reveals Key MicroRNAs in Myocardial Infarction

BACKGROUND: As playing important roles in gene regulation, microRNAs (miRNAs) are believed as indispensable involvers in the pathogenesis of myocardial infarction (MI) that causes significant morbidity and mortality. Working on a hypothesis that modulation of only some key members in the miRNA superfamily could benefit ischemic heart, we proposed a microarray based network biology approach to identify them with the recognized clinical effect of propranolol as a prompt. METHODS: A long-term MI model of rat was established in this study. The microarray technology was applied to determine the global miRNA expression change intervened by propranolol. Multiple network analyses were sequentially applied to evaluate the regulatory capacity, efficiency and emphasis of the miRNAs which dysexpression in MI were significantly reversed by propranolol. RESULTS: Microarray data analysis indicated that long-term propranolol administration caused 18 of the 31 dysregulated miRNAs in MI undergoing reversed expression, implying that intentional modulation of miRNA expression might show favorable effects for ischemic heart. Our network analysis identified that, among these miRNAs, the prime players in MI were miR-1, miR-29b and miR-98. Further finding revealed that miR-1 focused on regulation of myocyte growth, yet miR-29b and miR-98 stressed on fibrosis and inflammation, respectively. CONCLUSION: Our study illustrates how a combination of microarray technology and functional protein network analysis can be used to identify disease-related key miRNAs

TNFR1 and TNFR2 regulate the extrinsic apoptotic pathway in myeloma cells by multiple mechanisms

The huge majority of myeloma cell lines express TNFR2 while a substantial subset of them failed to show TNFR1 expression. Stimulation of TNFR1 in the TNFR1-expressing subset of MM cell lines had no or only a very mild effect on cellular viability. Surprisingly, however, TNF stimulation enhanced cell death induction by CD95L and attenuated the apoptotic effect of TRAIL. The contrasting regulation of TRAIL- and CD95L-induced cell death by TNF could be traced back to the concomitant NFκB-mediated upregulation of CD95 and the antiapoptotic FLIP protein. It appeared that CD95 induction, due to its strength, overcompensated a rather moderate upregulation of FLIP so that the net effect of TNF-induced NFκB activation in the context of CD95 signaling is pro-apoptotic. TRAIL-induced cell death, however, was antagonized in response to TNF because in this context only the induction of FLIP is relevant. Stimulation of TNFR2 in myeloma cells leads to TRAF2 depletion. In line with this, we observed cell death induction in TNFR1-TNFR2-costimulated JJN3 cells. Our studies revealed that the TNF-TNF receptor system adjusts the responsiveness of the extrinsic apoptotic pathway in myeloma cells by multiple mechanisms that generate a highly context-dependent net effect on myeloma cell survival

Ultraconserved Elements in the Olig2 Promoter

. basal promoter and found that it represses expression in undifferentiated embryonic stem cells. expression during development

An Alpha-Catulin Homologue Controls Neuromuscular Function through Localization of the Dystrophin Complex and BK Channels in Caenorhabditis elegans

The large conductance, voltage- and calcium-dependent potassium (BK) channel serves as a major negative feedback regulator of calcium-mediated physiological processes and has been implicated in muscle dysfunction and neurological disorders. In addition to membrane depolarization, activation of the BK channel requires a rise in cytosolic calcium. Localization of the BK channel near calcium channels is therefore critical for its function. In a genetic screen designed to isolate novel regulators of the Caenorhabditis elegans BK channel, SLO-1, we identified ctn-1, which encodes an α-catulin homologue with homology to the cytoskeletal proteins α-catenin and vinculin. ctn-1 mutants resemble slo-1 loss-of-function mutants, as well as mutants with a compromised dystrophin complex. We determined that CTN-1 uses two distinct mechanisms to localize SLO-1 in muscles and neurons. In muscles, CTN-1 utilizes the dystrophin complex to localize SLO-1 channels near L-type calcium channels. In neurons, CTN-1 is involved in localizing SLO-1 to a specific domain independent of the dystrophin complex. Our results demonstrate that CTN-1 ensures the localization of SLO-1 within calcium nanodomains, thereby playing a crucial role in muscles and neurons

α1A-Adrenergic Receptor Induces Activation of Extracellular Signal-Regulated Kinase 1/2 through Endocytic Pathway

G protein-coupled receptors (GPCRs) activate mitogen-activated protein kinases through a number of distinct pathways in cells. Increasing evidence has suggested that endosomal signaling has an important role in receptor signal transduction. Here we investigated the involvement of endocytosis in α1A-adrenergic receptor (α1A-AR)-induced activation of extracellular signal-regulated kinase 1/2 (ERK1/2). Agonist-mediated endocytic traffic of α1A-AR was assessed by real-time imaging of living, stably transfected human embryonic kidney 293A cells (HEK-293A). α1A-AR was internalized dynamically in cells with agonist stimulation, and actin filaments regulated the initial trafficking of α1A-AR. α1A-AR-induced activation of ERK1/2 but not p38 MAPK was sensitive to disruption of endocytosis, as demonstrated by 4°C chilling, dynamin mutation and treatment with cytochalasin D (actin depolymerizing agent). Activation of protein kinase C (PKC) and C-Raf by α1A-AR was not affected by 4°C chilling or cytochalasin D treatment. U73122 (a phospholipase C [PLC] inhibitor) and Ro 31–8220 (a PKC inhibitor) inhibited α1B-AR- but not α1A-AR-induced ERK1/2 activation. These data suggest that the endocytic pathway is involved in α1A-AR-induced ERK1/2 activation, which is independent of Gq/PLC/PKC signaling

Unusual synergistic effect in layered Ruddlesden-Popper oxide enables ultrafast hydrogen evolution

Efficient electrocatalysts for hydrogen evolution reaction are key to realize clean hydrogen production through water splitting. As an important family of functional materials, transition metal oxides are generally believed inactive towards hydrogen evolution reaction, although many of them show high activity for oxygen evolution reaction. Here we report the remarkable electrocatalytic activity for hydrogen evolution reaction of a layered metal oxide, Ruddlesden-Popper-type Sr2RuO4 with alternative perovskite layer and rock-salt SrO layer, in an alkaline solution, which is comparable to those of the best electrocatalysts ever reported. By theoretical calculations, such excellent activity is attributed mainly to an unusual synergistic effect in the layered structure, whereby the (001) SrO-terminated surface cleaved in rock-salt layer facilitates a barrier-free water dissociation while the active apical oxygen site in perovskite layer promotes favorable hydrogen adsorption and evolution. Moreover, the activity of such layered oxide can be further improved by electrochemistry-induced activation

The Kerr-Schild double copy in curved spacetime

We thank Tim Adamo, Ricardo Monteiro and Donal O’Connell for discussions and / or comments on the manuscript. CDW and NBA are supported by the U.K. Science and Technology Facilities Council (STFC). AL is funded by a Conacyt studentship, and thanks Queen Mary University of London for hospitalit