Divalent antibodies

Ismaili, A., Jalali-Javaran, M., Rasaee, M.J., Rahbarizadeh, E, Forouzandeh-Maghadam, M., and Memari, H.R. (2007). Production and characterization of anti-(mucin MUCl). single-divalent antibody in tobacco (Nicotiana tofcflCMm cultivarXanthi). Biotechnol. Appl. Biochem. 47(1) 11-19. 

It should also be noted that the valency of binding at equilibrium may also be influenced by antibody concentration (2). Thus, high divalent antibody concentrations drive binding to a predominantly monovalent state, whereas at lower concentrations, the binding may be predominantly divalent this obviously varies the antigen-antibody stoichiometry from near 2.1 to approaching 1 1. The best compromise when this effect is in operation may be to use an antibody concentration on the initial plateau of a saturation curve. Increases in... 

Fig. 28.15 The GnRH and GnRH receptor interaction. A dimer of the GnRH antagonist also serves as an antagonist, but when expressed linked to a divalent antibody it functions as an agonist. (Based on the work of Conn, see references 90 and 91.)...

Supramolecular Formation of Antibodies with Divalent Antigens 244... 

Here, we describe the design and preparation of antibody supramolecular complexes and their application to a highly sensitive detection method. The complex formation between antibodies (IgG) and multivalent antigens is investigated. When an antibody solution is mixed with divalent antigen, a linear or cyclic supramolecule forms [26-29]. With trivalent antigens, the antibody forms network structures. These supramolecular formations are utilized for the ampH-fication of detection signals on the biosensor techniques. 

Fig. 3. Haptens and multivalent antigens prepared in this syudy. The viologen derivative, 4,4 -bipyridinium, l-(carboxypentyl)-l -methyl-dichloride (1), divalent antigen 2, and trivalent antigen 3. Anti-porphyrin antibodies were elicited for [5-(4-carboxyphenyl)-10,15,20-tris-(4-methylpyridyl)]porphine (3MPylC) or meso-tetrakis(4-carboxyphenyl)porphine (TCPP). meso-Tetrakis(4-methylpyridyl)porphine (TMPyP) was used to investigate the specificity of the antibody dendrimer for porphyrins...

Scheme 1. Complex formation of antibodies (IgG) with divalent antigens...

An enhancement of SPR signal intensity was observed by the addition of the antibody to the divalent antigen-antibody complex immobilized onto the surface of the sensor chip, indicating the formation of linear supramolecules. An amplification method of the detection signals for a target molecule has been... 

An IgG-antibody against an individual ribosomal protein binds specifically only to this protein in a ribosomal subunit. Since the antibody is divalent it can form a bridge between the identical proteins in two subunits, leading to a dimer that can be examined under Ae electron microscope. The location of the bound antibody on the subunit surface can be determined, defining the position of the antigenic determinant of a particular protein. The method relies on the fact that IgG-antibodies are able to react with specific proteins within the intact ribosomal subunits and that both subunits have discernible shapes with recognizable morphological landmarks. 

It is very important in PAP techniques for the secondary antibody to be applied in excess. This way, one arm of the divalent Fab portion of the immunoglobulin molecule can bind the primary antibody, and the other arm is free to bind the PAP complex. If not in excess, both arms of the molecule may bind the primary antibody, creating a prozone-type of effect. Without a free secondary antibody Fab site to capture the PAP complex, the assay will not work. 

Unlike nickel, chromium metal does not produce allergic contact dermatitis. Some patients exhibit positive patch tests to divalent chromium compounds, but these compounds are considerably less potent as sensitizers than hexavalent chromium compounds. A case of chromium (chromic) sulfate-induced asthma in a plating worker, confirmed by specific challenge testing and the presence of IgE antibodies, has been reported. ... 

This immunometric assay employed an analog of the analyte (T2) as a ligand of immunosorbent, as in the example discussed in Section 3.1. The authors mentioned that the use of T2 molecules having low intrinsic affinity to the antibody but high avidity in the immobilized form on the CPG, through the use of divalent binding, obviated the need to prepare a monovalent labeled antibody. 

Fujisawa, K., Tani, P, and McMillan, R., Platelet-associated antibody to glycoprotein llb/Illa from chronic immune thrombocytopenia purpura patients often binds to divalent cation-dependent antigens. Blood l, 1284-1289 (1993). 

If the on rates for small hapten binding to antibody are close to diffusion limited, say, 108 //mole-s, then with k - 3 x 106 //mole we see that the lifetime of the state in which antibody is bound to lipid hapten is approximately 10 2 to 10 3 s. Thus for nitroxide hapten concentrations of the order of 0.3 mole %, each monovalent binding is expected to be followed by divalent binding, in the absence of steric restraints. This conclusion depends strongly on the assumptions, and the kinetics of divalent binding must decrease markedly for lower values of the hapten concentration and diffusion constant. 

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