Studies on the formation and function of SFV proteins

1. The growth cycle of SFV in chick embryo fibroblasts, BHK-2l, HEL and 1-929 cells was described, as were the resultant effects on RNA and protein synthesis. The release of haemagglutinin and LDH from infected ,cells was assayed, and shown to parallel the release')of infectious virus. The effect of altering the temperature of incubation on the growth of the virus, and the concommitant change in macromolecular synthesis , were investigated. There was a substantial inhibition of host cell protein synthesis from .3h after:.1nfection ward , under all the conditions investigated. 2. Five proteins could be readily detected in any of the four cell types when they had been infected with SFV for at least .3h. These five proteins were present throughout the growth cycle, whether the temperature o 0 0 of incubation was .30 C, .37 C or .39 C. Five proteins of the same size were also present in chick cells infected with Sindbis virus. Two of the five were the structural proteins, the other three were NVP 95, NVP 72 and NVP 63. 3. On the basis of its amino acid composition, its carbohydrate composition, and its kinetics of labelling, NVP 6.3 appears to be a precursor of the envelope protein. NVP 95 also contains some carbohydrate. 4. Pulse-chase experiments were carried out in infected chick and BHK- 21 cells. The information from these experiments vas supplemented with results from pulse-chase experiments in which the cells had been treated with TPCK,or NaF, or with amino acid analogues, or subjected to the reversal of a temperature jump. From these results, two further high molecular weight proteins became detectable, NVP 165 and ~1TP 127. It was possible to demonstrate that NVP 165, NVP 127 and NVP 95 and NVP 6.3 were precursors to NVP 72 and the structural proteins. Two models were proposed, based on the presence or absence of a second envelope protein. 5. The proteins present in the plasma membrane and endoplasmic reticulum were investigated The only protein contained in the plasma membrane was the envelope protein, while all the proteins normally found in infected cells were present in the endoplasmic reticulum fraction. 6. On the basis of the proteins synthesised on inhibition with cycloheximide and puromycin, and because of the timing or their formation, it was suggested that none or the proteins so far identified was the RNA polymerase. 7. A method for obtaining a partially purified preparation of the RNA polymerase was described. The RNA and protein species associated with the enzyme were analysed. The M band technique vas also utilised to obtain a further fractionation. By a combination of these methods, it was shown that the replicative intermediate is the first RNA species formed, while only NVP72 vas associated with the RNA polymerase. 8. An in vitro assay for the RNA polymerase was described. The product was replicative intermediate and replicative form. It was shown that the assay was not sensitive to antiserum preparations that neutralised the core or envelope proteins. 9. A method for pulse labelling the RNA was described, using the inhibition of macromolecular synthesis caused by glucosamine. It was demonstrated that the replicative intermediate was the first RNA species formed

The Pattern Recognition Receptor (RAGE) Is a Counterreceptor for Leukocyte Integrins: A Novel Pathway for Inflammatory Cell Recruitment

The pattern recognition receptor, RAGE (receptor for advanced glycation endproducts), propagates cellular dysfunction in several inflammatory disorders and diabetes. Here we show that RAGE functions as an endothelial adhesion receptor promoting leukocyte recruitment. In an animal model of thioglycollate-induced acute peritonitis, leukocyte recruitment was significantly impaired in RAGE-deficient mice as opposed to wild-type mice. In diabetic wild-type mice we observed enhanced leukocyte recruitment to the inflamed peritoneum as compared with nondiabetic wild-type mice; this phenomenon was attributed to RAGE as it was abrogated in the presence of soluble RAGE and was absent in diabetic RAGE-deficient mice. In vitro, RAGE-dependent leukocyte adhesion to endothelial cells was mediated by a direct interaction of RAGE with the β2-integrin Mac-1 and, to a lower extent, with p150,95 but not with LFA-1 or with β1-integrins. The RAGE–Mac-1 interaction was augmented by the proinflammatory RAGE-ligand, S100-protein. These results were corroborated by analysis of cells transfected with different heterodimeric β2-integrins, by using RAGE-transfected cells, and by using purified proteins. The RAGE–Mac-1 interaction defines a novel pathway of leukocyte recruitment relevant in inflammatory disorders associated with increased RAGE expression, such as in diabetes, and could provide the basis for the development of novel therapeutic applications

Efficacy of 23-valent pneumococcal vaccine in preventing pneumonia and improving survival in nursing home residents: double blind, randomised and placebo controlled trial

Objective To determine the efficacy of a 23-valent pneumococcal polysaccharide vaccine in people at high risk of pneumococcal pneumonia

RAGE Mediates a Novel Proinflammatory Axis A Central Cell Surface Receptor for S100/Calgranulin Polypeptides

AbstractS100/calgranulin polypeptides are present at sites of inflammation, likely released by inflammatory cells targeted to such loci by a range of environmental cues. We report here that receptor for AGE (RAGE) is a central cell surface receptor for EN-RAGE (e xtracellular n ewly identified RAGE-binding protein) and related members of the S100/calgranulin superfamily. Interaction of EN-RAGEs with cellular RAGE on endothelium, mononuclear phagocytes, and lymphocytes triggers cellular activation, with generation of key proinflammatory mediators. Blockade of EN-RAGE/RAGE quenches delayed-type hypersensitivity and inflammatory colitis in murine models by arresting activation of central signaling pathways and expression of inflammatory gene mediators. These data highlight a novel paradigm in inflammation and identify roles for EN-RAGEs and RAGE in chronic cellular activation and tissue injury