Antibody receptor

Binding proteins such as antibodies, receptors, and lectins may spontaneously aggregate in presence of bi- or multivalent specific ligands. This process, however, often results in assemblies that lack well-defined morphological and structural elements. 

The ProteinChip System from Ciphergen Biosystems uses patented SELDI (Surface-Enhanced Laser Desorption/Ionization) ProteinChip technology to rapidly perform the separation, detection, and analysis of proteins at the femtomole level directly from biological samples. ProteinChip Systems use ProteinChip Arrays which contain chemically (cationic, anionic, hydrophobic, hydrophilic, etc.) or biochemically (antibody, receptor, DNA, etc.) treated surfaces for specific interaction with proteins of interest. Selected washes create on-chip, high-resolution protein maps. This protein mass profile, or reten-tate map of the proteins bound to each of the ProteinChip Array surfaces, is quantitatively detected in minutes by the ProteinChip Reader. 

Drug Name Generic Name Company Antigen/ Antibody Receptor FDA Indication Approval ... 

A similar number of amino acids in other proteins are involved in binding specific molecules, e.g. an antigen to the antibody receptor protein on B lymphocytes, a neurotransmitter to the receptor in a postsynaptic nerve, a hormone or growth factor to a receptor on the surface of a cell. 

In any battle, when the defence is outnumbered by the enemy, more troops are brought into the battle from the reserve. However, in the immune system, there are initially no reserve troops. When an antigen binds to its complementary antibody-receptor on B-cells, these are strongly stimulated to proliferate (clonal expansion). In addition, not only does the number of daughter cells increase but each quickly develops into what is known as an effector (or plasma) cell, in which the protein synthetic machinery increases through the development of the rough endoplasmic reticulum, so that there is a large increase in the number of antibodies synthesised and secreted. A simple description of the sequence of events is as follows ... 

Next to the detection of enzyme inhibition, ESI-MS can also be used to monitor protein-ligand interaction, employing an assay format similar to fluorescence-based receptor assays. Using a similar continuous-flow analytical screening system as shown in Fig. 5.2, a competitive assay can be set up using ESI-MS to measure the interaction of the analyte(s) with an affinity protein such as an antibody, receptor or enzyme [28]. Figure 5.10 shows the equilibrium reactions that form the basis of the assay concept. In a first step, the sample was injected into a con-... 

Surface immobilization of the capture molecules follows standard procedures that are commonly practiced in many biosensor applications and some are discussed in the previous section. Layers of carboxymethyl dextran. Protein A or Protein G, streptavidin-coated surface, or EDC [N-ethyl-N-(diethylaminopropyl) carbidimide]/NHS (N-hydroxysuccmimide)-based amine coupling through amide bond are used for protein (antibody, receptor, etc.) cross-linking. 

As described in Part I, increases in affinity or avidity for antigen are characteristic features of the immune response. In antibody responses to well-defined haptenic determinants, the affinity of the antibodies for the hapten had been shown to increase during the period after immunization this was interpreted in terms of clonal selection, cells with antibody-receptors of higher affinity successfully competing for antigen against cells with receptors of lower affinity. 

Examination of presence of samples on array To verily that proteins, synthetic peptides, and carbohydrates are successfully printed, microarrays can be incubated with antibodies, receptors, or lectins known to react with the printed substance. The reaction is detected either by conjugating directly afluorochrome to the detector, or by a second-step staining procedure. 

A biosensor is a sensing device that is integrated within or intimately associated with a physical transducer. Such a system quantifies electronic signals arising from the interaction between a biosensor and an analyte of interest. Catalytic biosensors use enzymes, microorganisms, or whole cells to catalyze a reaction with the target analyte, while affinity biosensors utilize antibodies, receptors, or nucleic acids to bind with the target analyte. 

Gao, C., S. Mao and F. Ronca (2003). De novo identification of tumor-specific internalizing human antibody-receptor pairs by phage-display methods. J Immunol Methods 274(1-2) 185-198. 

Ngo, T. T., Khatter, N., and Avid, A. L. (1992). A synthetic ligand affinity gel mimicking immobilized bacterial antibody receptor for purification of immunoglobulin G.. Chromatogr. 597, 101-109. 

Biological Lectins, antibodies, receptors, DNA Enzymes, micro-organisms, abzymes, organelles, tissue... 

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