Search results for "Receptor"

Tuning antiviral CD8 T-cell response via proline-altered peptide ligand vaccination

2019

AbstractViral escape from CD8+cytotoxic T lymphocyte responses correlates with disease progression and represents a significant challenge for vaccination. Here, we demonstrate that CD8+T cell recognition of the naturally occurring MHC-I-restricted LCMV-associated immune escape variant Y4F is restored following vaccination with a proline-altered peptide ligand (APL). The APL increases MHC/peptide (pMHC) complex stability, rigidifies the peptide and facilitates T cell receptor (TCR) recognition through reduced entropy costs. Structural analyses of pMHC complexes before and after TCR binding, combined with biophysical analyses, revealed that although the TCR binds similarly to all complexes, t…

Novel host-specific iron acquisition system in the zoonotic pathogenVibrio vulnificus

2015

Summary Vibrio vulnificus is a marine bacterium associated with human and fish (mainly farmed eels) diseases globally known as vibriosis. The ability to infect and overcome eel innate immunity relies on a virulence plasmid (pVvbt2) specific for biotype 2 (Bt2) strains. In the present study, we demonstrated that pVvbt2 encodes a host-specific iron acquisition system that depends on an outer membrane receptor for eel transferrin called Vep20. The inactivation of vep20 did not affect either bacterial growth in human plasma or virulence for mice, while bacterial growth in eel blood/plasma was abolished and virulence for eels was significantly impaired. Furthermore, vep20 is an iron-regulated ge…

The Receptor Functions of Endogenous C1q, a Subcomponent of the First Component of Complement, on Peritoneal Macrophages

1982

Abstract C1q, the Fc recognizing subcomponent of the first complement component was shown to be synthesized by peritoneal macrophages. Evidence is presented that C1q serves during the secretion phase as Fc binding protein on the membrane of these macrophages. A dose-dependent inhibition of Fc rosette formation occured when the macrophages were pretreated with anti-C1q -F(ab') 2 . The C3b rosette formation was not affected. In addition, preincubation of peritoneal macrophages with anti-C1q -F(ab') 2 abolished specifically the polyanion mediated stimulation to secrete dose and time dependently lysosomal enzymes. There was no polyanion-induced enzyme release after incubation of polyanions with…

Activation of liver x receptors promotes polyunsaturated fatty acid synthesis and eicosanoid secretion in human macrophages

2014

Novel Porphyrin-Cholic Acid Conjugates as Receptors for Biologically Important Anions

2005

A series of novel receptors showing high binding affinity in aqueous media for biologically important anions are reported. These naturally chromophoric porphyrin-based receptors contain cholic acids connected via quaternary alkyl ammonium amido linkages.

Ein Bindungsstellenmodell für H2-Antagonisten vom 4-Pyrimidinon-Typ

1985

In einer Reihe von 17 Histamin-H2-antagonistisch wirksamen 5-substituierten 4-Pyrimidinonen wird durch Berechnung von Wechselwirkungsenergien ein Modell fur die Rezeptorbindungsstelle des Substituenten am C-5 des Pyrimidinons vorgeschlagen. Als Bindungsstelle fungiert die Aminosaure Arginin. A Binding Site Model for H2-Receptor Antagonists of the 4-Pyrimidone Type Based on calculations of the energies of interaction for a series of seventeen 5-substituted 4-pyrimidones with H2-antagonistic activity, a receptor binding site model for substituents at C-5 of the pyrimidone ring is proposed. The binding site is modeled using the amino acid arginine.

Sex Differences in Mitochondrial Antioxidant Gene Expression

2020

Females live longer than males. This could be in part due to the higher levels of estrogens in females, which protect them against aging. Physiological concentrations of estrogens have antioxidant effects as they induce the expression of manganese superoxide dismutase and glutathione peroxidase by stimulating estrogen receptors and the mitogen-activated protein kinase and nuclear factor kappa B pathways. However, estrogens can have undesirable effects such as they are feminizing to males, so other alternatives need to be searched. Phytoestrogens are good candidates as they can also bind to estrogens receptors, and in fact, they are able to mimic the antioxidant properties of estrogens. It i…

PPARgamma agonist pioglitazone does not enhance performance in mice

2013

Peroxisome-proliferator-activated receptor (PPAR) delta and adenosine monophosphate (AMP)-activated protein kinases (AMPKs) regulate the metabolic and contractile characteristics of myofibres. PPAR proteins are nuclear receptors that function as transcription factors and regulate the expression of multiple genes. AMPK has been described as a master metabolic regulator which also controls gene expression through the direct phosphorylation of some nuclear proteins. Since it was discovered that both PPARdelta agonists (GW1516) and AMPK activators (5-aminoimidazole-4-carboxamide-1-β-D-ribofuranoside, known as AICAR) are very effective performance-enhancing substances in sedentary mice, the Worl…

Bovine lactoferrin pepsin hydrolysate exerts inhibitory effect on angiotensin I-converting enzyme-dependent vasoconstriction

2007

Abstract The inhibitory effect of a pepsin hydrolysate of bovine lactoferrin (LFH) on angiotensin I-converting enzyme (ACE) has been examined using in vitro and ex vivo functional assays. In vitro assays showed a LFH inhibitory effect on ACE activity with an IC 50 value of 0.95±0.06 mg mL −1 . Ex vivo functional assays using rabbit carotid artery segments showed a LFH inhibitory effect on ACE-dependent angiotensin I-induced contraction, but not on angiotensin II-induced contraction, suggesting that the effect of LFH is not due to antagonism of receptors for angiotensin II. LFH was shown to possess ACE inhibitory effect with potential to modulate hypertension, although the possible inhibitor…

Effects of Administration of Glycoprotein IIb/IIIa Receptor Antagonists in Patients with Failed Thrombolysis

2001

Aim To evaluate the effectiveness of glycoprotein (GP) IIb/IIIa receptor antagonists in patients with acute myocardial infarction (AMI) who have undergone unsuccessful thrombolysis.