Pathogen specific antibody responses need to be tightly regulated to generate protective but limit self-reactive immune responses. While loss of humoral tolerance has been associated with microbial infections, the pathways involved in balancing protective versus autoreactive antibody responses in humans are incompletely understood. Studies in classical mouse model systems have provided evidence that balancing of immune responses through inhibitory receptors is an important quality control checkpoint. Genetic differences between inbred mouse models and the outbred human population and allelic receptor variants not present in mice, however, argue for caution when directly translating these findings to the human system. By studying Borrelia burgdorferi infection in humanized mice reconstituted with human hematopoietic stem cells from donors homozygous for a functional or non-functional FcgRIIb allele, we show that the human inhibitory FcgRIIb is a critical checkpoint balancing protective and autoreactive immune responses, linking infection with induction of autoimmunity in the human immune system.
- Falk Nimmerjahn
- Falk Nimmerjahn
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Animal experimentation: All animal experiments were performed in strict accordance to the rules and regulations of the German animal welfare law. All animal experiments were approved by the government of lower Franconia (Permit Numbers: 2532-2-469 and 2532.2-817-11).
- Tomohiro Kurosaki, Osaka University, Japan
- Received: January 20, 2020
- Accepted: July 2, 2020
- Accepted Manuscript published: July 2, 2020 (version 1)
© 2020, Danzer et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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