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1.
Human RSV is one of the most prevalent viral pathogens of early childhood for which no vaccine is available. Herein we provide an analysis of RSV epitope data to examine its application to vaccine design and development. Our objective was to provide an overview of antigenic coverage, identify critical antibody and T cell determinants, and then analyze the cumulative RSV epitope data from the standpoint of functional responses using a combinational approach to characterize antigenic structure and epitope location. A review of the cumulative data revealed, not surprisingly, that the vast majority of epitopes have been defined for the two major surface antigens, F and G. Antibody and T cell determinants have been reported from multiple hosts, including those from human subjects following natural infection, however human data represent a minority of the data. A structural analysis of the major surface antigen, F, showed that the majority of epitopes defined for functional antibodies (neutralizing and/or protective) were either shown to bind pre-F or to be accessible in both pre- and post-F forms. This finding may have has implications for on-going vaccine design and development. These interpretations are in agreement with previous work and can be applied in the larger context of functional epitopes on the F protein. It is our hope that this work will provide the basis for further RSV-specific epitope discovery and investigation into the nature of antigen conformation in immunogenicity. 相似文献
2.
Senescence-induced alteration in cell surface carbohydrates correlated using proton NMR spectroscopy and a lectin-based affinity-binding assay 总被引:1,自引:0,他引:1
Changes in the cell surface oligosaccharides in human fetal lung fibroblasts (IMR-90) are studied as the cells progress to senescence using nuclear magnetic resonance spectroscopy (NMR) and a biochemical assay. A lectin-based affinity-binding technique is used which measures the organization of carbohydrates on the cell surface. Proton NMR studies of the water in samples of frozen cell suspensions of young and old cells provide information on the local dynamics of the cell surface by monitoring the motion of bound water. Changes in the lectin binding density and affinity class distribution correlate with a decrease in the water proton linewidth in frozen cells. These observations reflect alterations in the conformation or structure of the cell surface oligosaccharides and local constituent water. 相似文献
3.
Generation of nitric oxide by human neutrophils 总被引:25,自引:0,他引:25
C D Wright A Mülsch R Busse H Osswald 《Biochemical and biophysical research communications》1989,160(2):813-819
Human neutrophils were evaluated for their ability to generate nitric oxide. Neutrophils incubated with superoxide dismutase at 37 degrees C produce nitrite anion at a rate of 1.8 nmols/2 x 10(6) cells/30 min, providing indirect evidence of nitric oxide production. Incubation of the neutrophils with concentrations of serum-opsonized zymosan, N-formyl-methionyl-leucyl-phenylalanine, or phorbol myristate acetate sufficient to stimulate the respiratory burst and lysosomal enzyme release caused no additional nitrite anion production. Glass wool-adherent neutrophils exhibited a similar dissociation of nitrite anion production from the respiratory burst and lysosomal enzyme release. Direct evidence for nitric oxide production was also obtained using nitric oxide-specific chemiluminescence. These results demonstrate that human neutrophils are capable of generating nitric oxide. 相似文献
4.
The phagovar variability of Listeria strains under the influence of virulent and temperate bacteriophages 总被引:1,自引:1,他引:0
Selected strains of Listeria spp. were challenged against a variety of bacteriophages usually employed for phage typing. The resistant mutants derived were characterized by the loss of sensitivity to defined groups of phages. When different phages were used in succession multiple mutants could be obtained. They eventually became insensitive to all phages employed. Our results indicate the possibility of shifting phagovars among Listeria strains grown in mixed culture, due to the potential action of free bacteriophages. 相似文献
5.
Long term oscillation in glycolysis 总被引:3,自引:0,他引:3
To increase the period of glycolytic oscillations in yeast extracts (Saccharomyces uvarum), the dependence of the period on pH, on concentrations of phosphate and enzymes, and on temperature has been studied. Stable oscillatory trans were obtained at a pH value of about 6.5. Increasing the phosphate and decreasing the enzyme concentrations as well as decreasing temperature lengthened the period. By dilution of the extract with buffer while maintaining the metabolite concentrations at their initial level the period could be successively prolonged from 20 min to about 6 h. 相似文献
6.
Induction and activity of NO synthase in bone-marrow-derived macrophages are independent of Ca2+. 下载免费PDF全文
S Hauschildt A Lückhoff A Mülsch J Kohler W Bessler R Busse 《The Biochemical journal》1990,270(2):351-356
The aim of the present study was to analyse whether an increase in the intracellular free Ca2+ concentration ([Ca2+]i) plays a role as a signal mediating synthesis of nitric oxide (NO) in bone-marrow-derived macrophages, either by stimulating induction of NO synthase or by regulating the activity of the enzyme. Therefore we compared the effects of various synthetic analogues of bacterial lipopeptide and of lipopolysaccharide (LPS) on NO production (assessed as nitrite formation during an incubation for 24 h) and on [Ca2+]i [measured with the fluorescent probe indo-1 (1-[2-amino-5-(6-carboxyindol-2-yl)phenoxy]-2- 2-(2'-amino-5'-methylphenoxy)ethane-NNN'N'-tetra-acetic acid)]. Strongly dissociating effects were evoked on nitrite formation and on [Ca2+]i by the stimuli. LPS was preferentially effective on nitrite formation, whereas the Ca2+ ionophore ionomycin and AlF3 induced increases only in [Ca2+]i. The lipopeptides N-palmitoyl-(S)-[2,3-bis(palmitoyloxy)-(2RS)- propyl]-(R)-cysteinylalanylglycine, N-palmitoyl-(S)-[2,3-bis(palmitoyloxy)- (2RS)-propyl]-(R)-cysteinylseryl-lysyl-lysyl-lysine and (S)-(1,2- dicarboxyhexadecyl)ethyl-N-palmitoylcysteinylseryl-lysyl-lys yl-lysine stimulated both parameters, but the maximal effects on nitrite formation and the shape of the dose-response curves did not parallel the effects on [Ca2+]i. Reduction of extracellular Ca2+ with EGTA significantly inhibited increases in [Ca2+]i, but did not change nitrite formation. Furthermore, NO synthesis in the cytosolic fraction of stimulated macrophages was not affected by Ca2+ over the concentration range 10 nM-2 microM. We conclude that increases in [Ca2+]i are not required for NO production in bone-marrow-derived macrophages. Thus the cellular regulation of NO production strikingly differs from that in the vascular endothelium, brain and adrenal gland. 相似文献
7.
8.
Paracrine functions of the coronary vascular endothelium 总被引:5,自引:0,他引:5
Ingrid Fleming Johann Bauersachs Rudi Busse 《Molecular and cellular biochemistry》1996,157(1-2):137-145
9.
Tail raising by baboon mothers toward immigrant males 总被引:1,自引:0,他引:1
C D Busse 《American journal of physical anthropology》1984,64(3):255-262
Behavioral responses of adult females to recently immigrated adult males were examined in two groups of chacma baboons in the Moremi Wildlife Reserve, Botswana. Mothers carrying infants respond negatively by raising their tails, avoiding, and screaming when in proximity to immigrant males. These responses are not given by mothers when their infants are away from them or by females who do not have infants. Also, the negative responses by mothers carrying infants are given only to immigrant males and not to long-term resident males. These observations are in concordance with the growing evidence of infanticide in savanna baboon societies: mothers would be expected to show negative responses to potentially aggressive males, particularly immigrants. There was evidence to suggest that mothers respond negatively to immigrants only insofar as these males could not have sired their infants. If confirmed by subsequent observations, this result would lend support to the sexual selection model of infanticide. 相似文献
10.