Functional affinity

Borman, A. M., Michel, Y. M., and Kean, K. M. (2000). Biochemical characterization of cap-poly(A) synergy in rabbit reticulocyte lysates The eIF4G-PABP interaction increases the functional affinity of eIF4E for the capped mRNA 5r-end. Nucleic Acids Res. 28, 4068-4075. 

Antibodies from hyperimmunized animals not only differ with regard to the determinants they recognize on multivalent antigens, but also differ in their affinities for the same. The term affinity has been used to describe both intrinsic and functional affinities (4). 

The functional affinities of the humanized antibody for the target protein on human and cynomolgous cells were computed to be 0.05 and 0.03 nM, respectively. These results indicated that the humanized MAb bound with similar affinity to the target receptor on human and cynomolgus cells. 

Marzocchi-Machado CM, Polizello AC, Azzolini AE, Lucisano-Valim YM. The influence of antibody functional affinity on the effector functions involved in the clearance of circulating immune complexes anti-BSA IgG/BSA. Immunol Invest 1999 28(2-3) 89—101. 

The simultaneous interaction of multiple saccharide epitopes of polyvalent ligands with oligomeric receptors can lead to interactions of high functional affinity when the orientation of the saccharide recognition elements corresponds to that of the receptor (O Fig. 8). The mechanism of affinity increase is often described as the chelate effect [52,53]. This idea is... 

By appending sLe epitopes to an aromatic template and functionalizing the amino group of sLe with a large, hydrophobic residue 21 (O Fig. 15), a compound more effective (8-fold) than the aforementioned dimers was generated. The small increases in functional affinities obtained with these bivalent compounds suggest that they may make favorable contacts outside of the... 

Although some structural features can influence the activity of the dendrimers [111], Roy s studies identified few major differences between dendrimers of different structure. If the dendrimers were acting via the chelate effect, changes in the distance between epitopes would be expected to perturb their functional affinity significantly. As stated above, however, the dendrimers crosslink their target proteins. Because small variations in their structure are unlikely... 

For other tissues, in particular those of the lower urinary tract, the situation is, in our opinion, less clear. From one dde there is convincing evidence of the fimctional relevance for human prostate of the ttj -AR [17,18,73], in addition to analysis of mRNA expresdon [74,75] and to radioreceptor binding studies [20,76]. On the other hand, redstance to CEC and low afGnity for prazosin suggest that the functional affinity to this tissue could be due to the a -AR [8,77,46]. Listed in Table 2 are the fimctional and receptor binding results of some selected antagonists, in an attenq>t to clarify this issue. 

Affinity of selected Oj-AR antagonists for the recombinant animal a,-AR subtypes (pKi= -log,, nM) and functional affinity for the Oj-ARs of vascular and lower urinary tract tissues (pKb= -logj Kb, nM, for inhibition of NA-induced contraction). R.A.= rat aorta RB.A.= rabbit aorta RB.U.= rabbit urethra H.P.=human prostate. The in vivo effects after i.v. administration in the dog model are also listed. Data represent the doses (pg/kg) active in inhibiting by 50% the urethral contractions induced by NA (UP), the doses active in lowering diastolic blood pressure (DBP) by 25%, and the ratio between them. The ratios between the in vitro potency (Kb) on rabbit aorta and urethra are also reported (1/2). 

A number of specific components contribute to the complex energetics of lectin-ligand interactions. The observed affinities (functional affinities, see Section ll.B.l)... 

Figure 12 Kiessling s C-gluco- (8) and mannopyranosides (9) demonstrate increased functional affinity and specificity when displayed as bivalent mannose (13) and glucose (12) ligands.

Several groups have generated sialic acid substituted acrylamide polymers and investigated the abilities of these materials to inhibit influenza virus HA [101,162, 166,170,174]. In these investigations, the mole fraction of A-acetylneuraminic acid (NeuAc) residues displayed by the different acrylamide polymers has been varied. The potency of the materials generated depends on the degree of substitution on the polymers. Maximal polymer activity was observed when approximately 10-20% of the units were substituted with NeuAc. Lower amounts of substitution resulted in decreased functional affinities, presumably because these materials were less likely... 

Although low molecular weight displays have not exhibited high functional affinities for the selectins, larger multivalent ligands are more effective inhibitors. For exam-... 

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