The DNA double-strand break (DSB) repair factor 53BP1 has long been implicated in V(D)J and class switch recombination (CSR) of mammalian lymphocyte receptors. However, the dissection of the underlying molecular activities is hampered by a paucity of studies [V(D)J] and plurality of phenotypes (CSR) associated with 53BP1 deficiency. Here, we revisit the currently accepted roles of 53BP1 in antibody diversification in view of the recent identification of its downstream effectors in DSB protection and latest advances in genome architecture. We propose that, in addition to end protection, 53BP1-mediated end-tethering stabilization is essential for CSR. Furthermore, we support a pre-DSB role during V(D)J recombination. Our perspective underscores the importance of evaluating repair of DSBs in relation to their dynamic architectural contexts.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/j.it.2023.08.004 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
RIF1 integrates DNA repair and transcriptional requirements during the establishment of humoral immune responses.
Nat Commun
January 2025
Laboratory of Genome Diversification & Integrity, Max Delbrück Center for Molecular Medicine in the Helmholtz Association, 13125, Berlin, Germany.
The establishment of protective immune responses relies on the ability of terminally differentiated B cells to secrete a broad variety of antigen-specific antibodies with different effector functions. RIF1 is a multifunctional protein that promotes antibody isotype diversification via its DNA end protection activity during class switch recombination. In this study, we showed that RIF1 ablation resulted in increased plasmablast formation ex vivo and enhanced terminal differentiation into plasma cells upon immunization.
View Article and Find Full Text PDFAntigen affinity and site of immunization dictate B cell recall responses.
Cell Rep
January 2025
Department of Microbiology, Tumor and Cell Biology, Division of Virology and Immunology, Karolinska Institutet, 171 65 Solna, Sweden. Electronic address:
Protective antibodies against HIV-1 require unusually high levels of somatic mutations introduced in germinal centers (GCs). To achieve this, a sequential vaccination approach was proposed. Using HIV-1 antibody knockin mice with fate-mapping genes, we examined if antigen affinity affects the outcome of B cell recall responses.
View Article and Find Full Text PDFMutability and hypermutation antagonize immunoglobulin codon optimality.
Mol Cell
January 2025
Drukier Institute for Children's Health, Department of Pediatrics, Weill Cornell Medicine, New York, NY, USA. Electronic address:
The efficacy of antibody responses is inherently linked to paratope diversity, as generated through V(D)J recombination and somatic hypermutation. Despite this, it is unclear how genetic diversification mechanisms evolved alongside codon optimality and affect antibody expression. Here, we analyze germline immunoglobulin (IG) genes, natural V(D)J repertoires, serum IgG, and monoclonal antibody (mAb) expression through the lens of codon optimality.
View Article and Find Full Text PDFProbing TCR Specificity Using Artificial In Vivo Diversification of CDR3 Regions.
Eur J Immunol
January 2025
Department of Developmental Immunology, Max Planck Institute of Immunobiology and Epigenetics, Freiburg, Germany.
The T-cell receptor sequences expressed on cells recognizing a specific peptide in the context of a given MHC molecule can be explored for common features that might explain their antigen specificity. However, despite the development of numerous experimental and bioinformatic strategies, the specificity problem remains unresolved. To address the need for additional experimental paradigms, we report here on an in vivo experimental strategy designed to artificially diversify a transgenic TCR by CRISPR/Cas9-mediated mutagenesis of Tcra and Tcrb chain genes.
View Article and Find Full Text PDFClonal Variant Analysis of Antibody Engineering Libraries.
Cold Spring Harb Protoc
January 2025
The Ragon Institute of Massachusetts General Hospital, Massachusetts Institute of Technology, and Harvard University, Cambridge, Massachusetts 02139, USA
In vitro antibody evolution is a powerful technique for improving monoclonal antibodies. This can be achieved by generating artificial diversity on an antibody template, which can be done using different in vitro diversification techniques. The resulting libraries consist of single- or multimutant variants of a defined antibody template that are screened for improved function using antibody display.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!