Open AccessGlycation of monoclonal antibodies impairs their ability to bind antigen
Author(s) -
KENNEDY D. M.,
SKILLBN A. W.,
SELF C. H.
Publication year - 1994
Publication title -
clinical & experimental immunology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.329
H-Index - 135
eISSN - 1365-2249
pISSN - 0009-9104
DOI - 10.1111/j.1365-2249.1994.tb06133.x
Subject(s) - glycation , chemistry , antigen , antibody , monoclonal antibody , surface plasmon resonance , dissociation constant , endocrinology , medicine , microbiology and biotechnology , biochemistry , immunology , receptor , biology , materials science , nanoparticle , nanotechnology
SUMMARY As elevated levels of glycated IgG have been detected in the plasma of patients with diabetes mellitus, a disease associated with increased susceptibility to infection, we have investigated whether glycation of MoAbs affects the kinetics and/or affinity of antigen binding. Three mouse MoAbs were incubated with 0.5 M glucose at pH 7.4 for 14‐1 days at 37°C. Control MoAbs were incubated using identical conditions but with no added glucose. Using a surface plasmon resonance technique we found that glycation significantly increased the rate of dissociation (k diss ) of the antigen‐antibody complex for all three MoAbs ( P < 0.05, n = 4), but had no significant effect on the rate of association (k ass ). For one of the MoAbs, against human IgG (Fab), we also measured k diss by an alternative method utilizing radiolabelled antigen, which confirmed that glycation of the antibody significantly increases k diss ( P < 0.001. n = 8). We also found using an ELISA‐based method that glycation of the same MoAb significantly increased (he equilibrium dissociation constant (k d ) ( P < 0.05, n = 6). A significant increase in k d was observed after glycation using glucose concentrations consistent with those found in poorly controlled diabetics ( P < 0.02, n = 5). We conclude that in vitro glycation can significantly lower the affinity of an antibody for its antigen, and significantly increases the rate of dissociation of the antigen antibody complex.