Antibody-binding domain

The minimum antibody binding domain, Fv, has also been linked to toxin to produce a more compact, recombinant immuno-toxin. The recombinant F -toxin appears to be more stable and exhibits less liver accumulation [27,28]. The immunogenicity of Fv-toxin as a consequence of the highly antigenic determinants of bacterial toxin remains a barrier to development. 

The affinity of the antibody binding domain, Fv, displayed by phage can be directly measured by determining the affin-... 

MFE23 (Fv) TNF-a MFE23 contains Fv amino-acid sequences of antibody binding domain Binds to carcinoembryonic antigen (CEA) expressed on many cancer cells TNF-a Tumoricidal activity and associated inflammatory responses The F, domain of MFE23 antibody fragment increases the target selectivity of TNF in mice [107,108]... 

Henning P, Andersson K M, Frykholm K, et al. (2005). Tumor cell targeted gene delivery by adenovirus 5 vectors carrying knobless fibers with antibody-binding domains. Gene Ther. 12 211-224. 

T-cell receptors (TCR) are heterodimeric transmembrane glycoproteins found exclusively in T cells, with extracellular domains that closely resemble antibody Fab structures. Each of the TCR a and p chains forms half of an extracellular antigen-binding domain, and in addition has one transmembrane... 

FIGURE 1.11 Three -dimensional spacefilling representation of part of a protein molecule, the antigen-binding domain of immunoglobulin G (IgG). Immunoglobulin G is a major type of circulating antibody. Each of the spheres represents an atom in the structure. 

FIGURE 1.12 Van der Waals packing is enhanced in molecules that are structurally complementary. Gln represents a surface protuberance on the protein lysozyme. This protuberance fits nicely within a pocket (formed by Tyr , Tyr , Phe and Trp ) in the antigen-binding domain of an antibody raised against lysozyme. (See also Figure 1.16.)... 

In another study, the original repetitive Cio, (AGAGAGPEG)io, center was reconstructed into nine repeats of AGAGAGPEG with three distributed repeats of the RGD sequence. The new triblock protein, composed of acidic and basic terminal domains in addition to the reconstructed central block, has been shown to support adhesion, spreading, and polarization of human fibroblast cells [82]. Triblock polypeptides that facilitate antibody binding have also been reported [83]. 

Callahan LN, Phelan M, Mallinson M, Norcross MA. Dextran sulfate blocks antibody binding to the principal neutralizing domain of human immunodeficiency virus type 1 without interfering with gpl20-CD4 interactions. J Virol 1991 65 1543-1550. 

The conformation and orientation of adsorbed proteins has been examined with monoclonal antibodies that recognize a specific site in a protein of interest. Keselowsky et al. examined the conformation of Fn adsorbed to SAMs that carried methyl, hydroxyl, carboxyl, and amine groups [79]. They used monoclonal antibodies that recognized the central cell-binding domain of Fn near the RGD motif. Different SAM functionalities differentially modulated the binding affinities of the monoclonal antibodies (OH > COOH = NH2 > CH3). The strength of cell adhesion to these... 

In an immune response, antibodies are produced and secreted by the B-lymphocytes in conjunction with the T, cells. In the majority of hapten-carrier systems, the B cells end up producing antibodies that are specific for both the hapten and the carrier. In these cases, the T lymphocytes will have specific-binding domains on the carrier, but will not recognize the hapten alone. In a kind of synergism, the B- and T-cells cooperate to induce a hapten-specific antibody response. After such an immune response has taken place, if the host is subsequently challenged with only the hapten, usually it will respond by producing hapten-specific antibodies from memory cells formed after the initial immunization. For a review of immunobiology (see Janeway, 2004). 

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