Advanced

Conformational isomerism of IgG antibodies

Hansson, Ulla-Britt; Wingren, Christer LU and Alkner, Ulf (1997) In BBA - Protein Structure and Molecular Enzymology 1340(1). p.53-62
Abstract
The purpose of this study was to determine why apparently homogeneous IgG antibodies were, in some cases, fractionated into at least two components by liquid-liquid partition chromatography (LLPC) in an aqueous two-phase system. Four mouse monoclonal IgG antibodies, two against albumin, one against IgG and one against thyroxine, were shown to adopt different conformational isomeric forms. The four antibodies existed in an equilibrium between two or three conformational forms, the proportion of which could also be estimated by LLPC. Since LLPC detects mainly conformational differences within the antigen-binding sites of IgG antibodies, it could be concluded that the conformational forms differed with respect to their combining sites.... (More)
The purpose of this study was to determine why apparently homogeneous IgG antibodies were, in some cases, fractionated into at least two components by liquid-liquid partition chromatography (LLPC) in an aqueous two-phase system. Four mouse monoclonal IgG antibodies, two against albumin, one against IgG and one against thyroxine, were shown to adopt different conformational isomeric forms. The four antibodies existed in an equilibrium between two or three conformational forms, the proportion of which could also be estimated by LLPC. Since LLPC detects mainly conformational differences within the antigen-binding sites of IgG antibodies, it could be concluded that the conformational forms differed with respect to their combining sites. Moreover, the isomeric forms of an antibody directed against a protein antigen, formed antigen-antibody complexes with almost identical surface properties. In contrast, complexes with different surface properties were formed when the hapten or hapten conjugated to BSA was bound. Thus, both the conformational isomers could bind antigen, at least when the antigen was a small hapten or a hapten conjugated to a carrier protein. Our results suggest that six out of 57 monoclonal IgG antibodies exist in equilibrium between at least two conformational forms and the biological significance of this isomerism is discussed. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Antigen binding, Conformational isomerism, IgG antibody, Phase partition, Liquid-liquid partition chromatography, Surface property
in
BBA - Protein Structure and Molecular Enzymology
volume
1340
issue
1
pages
53 - 62
publisher
Elsevier
external identifiers
  • scopus:0030982015
ISSN
0167-4838
DOI
10.1016/S0167-4838(97)00028-9
language
English
LU publication?
yes
id
a1334d2a-fc43-449f-aa47-6f6710111c81 (old id 126164)
date added to LUP
2007-07-05 13:46:24
date last changed
2017-08-20 04:15:41
@article{a1334d2a-fc43-449f-aa47-6f6710111c81,
  abstract     = {The purpose of this study was to determine why apparently homogeneous IgG antibodies were, in some cases, fractionated into at least two components by liquid-liquid partition chromatography (LLPC) in an aqueous two-phase system. Four mouse monoclonal IgG antibodies, two against albumin, one against IgG and one against thyroxine, were shown to adopt different conformational isomeric forms. The four antibodies existed in an equilibrium between two or three conformational forms, the proportion of which could also be estimated by LLPC. Since LLPC detects mainly conformational differences within the antigen-binding sites of IgG antibodies, it could be concluded that the conformational forms differed with respect to their combining sites. Moreover, the isomeric forms of an antibody directed against a protein antigen, formed antigen-antibody complexes with almost identical surface properties. In contrast, complexes with different surface properties were formed when the hapten or hapten conjugated to BSA was bound. Thus, both the conformational isomers could bind antigen, at least when the antigen was a small hapten or a hapten conjugated to a carrier protein. Our results suggest that six out of 57 monoclonal IgG antibodies exist in equilibrium between at least two conformational forms and the biological significance of this isomerism is discussed.},
  author       = {Hansson, Ulla-Britt and Wingren, Christer and Alkner, Ulf},
  issn         = {0167-4838},
  keyword      = {Antigen binding,Conformational isomerism,IgG antibody,Phase partition,Liquid-liquid partition chromatography,Surface property},
  language     = {eng},
  number       = {1},
  pages        = {53--62},
  publisher    = {Elsevier},
  series       = {BBA - Protein Structure and Molecular Enzymology},
  title        = {Conformational isomerism of IgG antibodies},
  url          = {http://dx.doi.org/10.1016/S0167-4838(97)00028-9},
  volume       = {1340},
  year         = {1997},
}