Variable region identical immunoglobulins differing in isotype express different paratopes

The finding that the antibody (Ab) constant (C) region can influence fine specificity suggests that isotype switching contributes to the generation of Ab diversity and idiotype restriction. Despite the centrality of this observation for diverse immunological effects such as vaccine responses, isotype-restricted antibody responses, and the origin of primary and secondary responses, the molecular mechanism(s) responsible for this phenomenon are not understood. In this study, we have taken a novel approach to the problem by probing the paratope with (15)N label peptide mimetics followed by NMR spectroscopy and fluorescence emission spectroscopy. Specifically, we have explored the hypothesis that the C region imposes conformational constraints on the variable (V) region to affect paratope structure in a V region identical IgG(1), IgG(2a), IgG(2b), and IgG(3) mAbs. The results reveal isotype-related differences in fluorescence emission spectroscopy and temperature-related differences in binding and cleavage of a peptide mimetic. We conclude that the C region can modify the V region structure to alter the Ab paratope, thus providing an explanation for how isotype can affect Ab specificity.

Medienart:

E-Artikel

Erscheinungsjahr:

2012

Erschienen:

2012

Enthalten in:

Zur Gesamtaufnahme - volume:287

Enthalten in:

The Journal of biological chemistry - 287(2012), 42 vom: 12. Okt., Seite 35409-35417

Sprache:

Englisch

Beteiligte Personen:

Janda, Alena [VerfasserIn]
Eryilmaz, Ertan [VerfasserIn]
Nakouzi, Antonio [VerfasserIn]
Cowburn, David [VerfasserIn]
Casadevall, Arturo [VerfasserIn]

Links:

Volltext

Themen:

Antibodies, Monoclonal, Murine-Derived
Immunoglobulin Constant Regions
Immunoglobulin G
Immunoglobulin Variable Region
Journal Article
Research Support, N.I.H., Extramural

Anmerkungen:

Date Completed 31.12.2012

Date Revised 01.02.2024

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1074/jbc.M112.404483

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM22058284X