Isotype switching in human memory B cells sets intrinsic antigen-affinity thresholds that dictate antigen-driven fates

Memory B cells (MBCs) play a critical role in protection against homologous and variant pathogen challenge by either differentiating to plasma cells (PCs) or to germinal center (GC) B cells. The human MBC compartment contains both switched IgG+ and unswitched IgM+ MBCs; however, whether these MBC subpopulations are equivalent in their response to B cell receptor cross-linking and their resulting fates is incompletely understood. Here, we show that IgG+ and IgM+ MBCs can be distinguished based on their response to κ-specific monoclonal antibodies of differing affinities. IgG+ MBCs responded only to high-affinity anti-κ and differentiated almost exclusively toward PC fates. In contrast, IgM+ MBCs were eliminated by apoptosis by high-affinity anti-κ but responded to low-affinity anti-κ by differentiating toward GC B cell fates. These results suggest that IgG+ and IgM+ MBCs may play distinct yet complementary roles in response to pathogen challenge ensuring the immediate production of high-affinity antibodies to homologous and closely related challenges and the generation of variant-specific MBCs through GC reactions.

Medienart:

E-Artikel

Erscheinungsjahr:

2024

Erschienen:

2024

Enthalten in:

Zur Gesamtaufnahme - volume:121

Enthalten in:

Proceedings of the National Academy of Sciences of the United States of America - 121(2024), 13 vom: 26. März, Seite e2313672121

Sprache:

Englisch

Beteiligte Personen:

Ambegaonkar, Abhijit A [VerfasserIn]
Holla, Prasida [VerfasserIn]
Sohn, Haewon [VerfasserIn]
George, Rachel [VerfasserIn]
Tran, Tuan M [VerfasserIn]
Pierce, Susan K [VerfasserIn]

Links:

Volltext

Themen:

Affinity thresholds
Antigens
B cell receptor isotype
Immunoglobulin G
Immunoglobulin M
Journal Article
Memory B cells

Anmerkungen:

Date Completed 21.03.2024

Date Revised 05.04.2024

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1073/pnas.2313672121

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM369923332