Search results for "PLASMA"

Influence of antibody binding on oxygen binding behavior of Panulirus interruptus hemocyanin

1997

Oxygen binding behavior of monomeric subunit a and the hexameric form of this subunit of hemocyanin of Panulirus interruptus is influenced by the binding of various monoclonal antibodies. These antibodies react with other surface parts of the subunit than its second domain in which the oxygen binding site is located. The influence of three monoclonal antibodies and their antigen binding fragments (F-ab) has been investigated. Two antibodies increase the oxygen affinity of monomeric hemocyanin from that observed in its low affinity T-state, while the third has little influence on this property. F-ab fragments abolish almost completely the cooperativity of oxygen binding by the hexameric hemo…

Thin-layer affinity chromatography in analysis of protein-ligand affinity.

1996

Heparan sulfate proteoglycans interact exclusively with conformationally intact HPV L1 assemblies: basis for a virus-like particle ELISA.

2004

In this article, we demonstrate that interaction of human papillomavirus-like particles (HPV-VLPs) with the putative glucosaminoglycan binding receptor is strictly dependent on conformational integrity. Such conformations are present on VLPs and capsomeres but not on monomers of the major capsid protein, L1, confirming reports that capsomeres can induce virus-neutralizing antibodies. Furthermore, we show the suitability of this specific interaction for development of VLP-based enzyme-linked immunosorbent assays (ELISAs), using heparin for indirect coupling of VLPs to microtiter plates, which may add an intrinsic quality control. This avoids presentation of linear, often highly cross-reactiv…

Heavy Metals and Human Health: Possible Exposure Pathways and the Competition for Protein Binding Sites

2021

Heavy metals enter the human body through the gastrointestinal tract, skin, or via inhalation. Toxic metals have proven to be a major threat to human health, mostly because of their ability to cause membrane and DNA damage, and to perturb protein function and enzyme activity. These metals disturb native proteins’ functions by binding to free thiols or other functional groups, catalyzing the oxidation of amino acid side chains, perturbing protein folding, and/or displacing essential metal ions in enzymes. The review shows the physiological and biochemical effects of selected toxic metals interactions with proteins and enzymes. As environmental contamination by heavy metals is one of the most…

RNA-binding ability of PIPP in requires the entire protein

2003

Post-transcriptional fate of eukaryotic mRNAs depends on association with different classes of RNA-binding proteins (RBPs). Among these proteins, the cold-shock domain (CSD)-containing proteins, also called Y-box proteins, play a key role in controlling the recruitment of mRNA to the translational machinery, in response to environmental cues, both in development and in differentiated cells. We recently cloned a rat cDNA encoding a new CSD-protein that we called PIPPin. This protein also contains two putative double-stranded RNA-binding motifs (PIP(1) and PIP(2)) flanking the central CSD, and is able to bind mRNAs encoding H1 degrees and H3.3 histone variants. In order to clarify the role of…

The membrane proximal cytokine receptor domain of the human interleukin-6 receptor is sufficient for ligand binding but not for gp130 association.

1998

Interleukin-6 (IL-6) belongs to the family of the "four-helix bundle" cytokines. The extracellular parts of their receptors consist of several Ig- and fibronectin type III-like domains. Characteristic of these receptors is a cytokine-binding module consisting of two such fibronectin domains defined by a set of four conserved cysteines and a tryptophan-serine-X-tryptophan-serine (WSXWS) sequence motif. On target cells, IL-6 binds to a specific IL-6 receptor (IL-6R), and the complex of IL-6.IL-6R associates with the signal transducing protein gp130. The IL-6R consists of three extracellular domains. The NH2-terminal Ig-like domain is not needed for ligand binding and signal initiation. Here w…

Biological properties of extracellular vesicles and their physiological functions

2015

The authors wish to thank Dr R Simpson and Dr D Taylor for critical reading of the manuscript and acknowledge the Horizon 2020 European Cooperation in Science and Technology programme and its support of our European Network on Microvesicles and Exosomes in Health & Disease (ME-HaD; BM1202 www.cost.eu/COST_Actions/bmbs/Actions/BM1202). In the past decade, extracellular vesicles (EVs) have been recognized as potent vehicles of intercellular communication, both in prokaryotes and eukaryotes. This is due to their capacity to transfer proteins, lipids and nucleic acids, thereby influencing various physiological and pathological functions of both recipient and parent cells. While intensive invest…

Automated Cancer Marker Characterization in Human Plasma Using SUrface PLASMON Resonance in Array combined with Mass Spectrometry (SUPRA-MS)

2012

International audience; The combination of Surface Plasmon Resonance technology with Mass Spectrometry becomes a key method for the characterization of targeted proteins in the fields of diagnosis and functional proteomics. We demonstrated in this work the ability of our SPRi-chip to capture targeted protein in biological fluids and in situ analyze by MS and MS/MS modes through automated procedure to go beyond classical immunoassays. Here, we established a proof of concept of SUPRA-MS for the detection, the identification and the characterization of a potential breast cancer marker.

Nanoparticle Size Is a Critical Physicochemical Determinant of the Human Blood Plasma Corona: A Comprehensive Quantitative Proteomic Analysis

2011

In biological fluids, proteins associate with nanoparticles, leading to a protein "corona" defining the biological identity of the particle. However, a comprehensive knowledge of particle-guided protein fingerprints and their dependence on nanomaterial properties is incomplete. We studied the long-lived ("hard") blood plasma derived corona on monodispersed amorphous silica nanoparticles differing in size (20, 30, and 100 nm). Employing label-free liquid chromatography mass spectrometry, one- and two-dimensional gel electrophoresis, and immunoblotting the composition of the protein corona was analyzed not only qualitatively but also quantitatively. Detected proteins were bioinformatically cl…

The impact of whole blood processing and freezing conditions on the quality of therapeutic plasma prepared from whole blood

2014

Background The quality of whole blood (WB)-derived plasma preparations has been the subject of several studies, but there has been a lack of robust, comparative data for the different methods of processing and freezing. Study Design and Methods Six WB-derived plasma units were pooled and split (n = 16) and frozen within either 8 or 24 hours after WB collection, stored at 4°C or at room temperature (RT), and then frozen either slowly at −20°C or rapidly to below −30°C. Plasma units were tested for fibrinogen, Factor (F)V, FVII, FVIII, FXI, and von Willebrand factor (VWF), protein C (PC), protein S (PS) activity and free PS, prothrombin time, and partial thromboplastin time. Results FVIII was…