Partial Rag Deficiency in Humans Induces Dysregulated Peripheral Lymphocyte Development and Humoral Tolerance Defect With Accumulation of T-Bet+ B Cells

Partial RAG deficiency in humans induces dysregulated peripheral lymphocyte development and humoral tolerance defect with accumulation of T-bet+ B cells

Krisztian Csomos, Boglarka Ujhazi, Peter Blazso, Jose L. Herrera, Christopher M. Tipton, Tomoki Kawai, Sumai Gordon, Maryssa Ellison, Kevin Wu, Matthew Stowell, Lauren Haynes, Rachel Cruz, Bence Zakota, Johnny Nguyen, Michelle Altrich, Christoph B. Geier, Svetlana Sharapova, Joseph F. Dasso, Jennifer W. Leiding, Grace Smith, Waleed Al-Herz, Mayra de Barros Dorna, Olajumoke Fadugba, Eva Fronkova, Veronika Kanderova, Michael Svaton, Sarah E. Henrickson, Joseph D. Hernandez, Taco Kuijpers, Snezhina Mihailova Kandilarova, Elizaveta Naumova, Tomas Milota, Anna Sediva, Despina Moshous, Benedicte Neven, Tara Saco, Ravishankar Sargur, Sinisa Savic, John Sleasman, Gauri Sunkersett, Brant R. Ward, Masanobu Komatsu, Stefania Pittaluga, Attila Kumanovics, Manish J. Butte, Michael P. Cancro, Shiv Pillai, Eric Meffre, Luigi D. Notarangelo & Jolan E. Walter. Nature Immunology. 2022 July 28. doi.org/10.1038/s41590-022-01271-6 IF: 30,153

doc. MUDr. Eva Froňková, Ph.D.

doc. MUDr. Eva Froňková, Ph.D., Klinika dětské hematologie a onkologie 2. LF UK a FN Motol

Abstract

The recombination-activating genes (RAG) 1 and 2 are indispensable for diversifying the primary B cell receptor repertoire and pruning self-reactive clones via receptor editing in the bone marrow; however, the impact of RAG1/RAG2 on peripheral tolerance is unknown. Partial RAG deficiency (pRD) manifesting with late-onset immune dysregulation represents an ‘experiment of nature’ to explore this conundrum. By studying B cell development and subset-specific repertoires in pRD, we demonstrate that reduced RAG activity impinges on peripheral tolerance through the generation of a restricted primary B cell repertoire, persistent antigenic stimulation and an inflammatory milieu with elevated B cell-activating factor. This unique environment gradually provokes profound B cell dysregulation with widespread activation, remarkable extrafollicular maturation and persistence, expansion and somatic diversification of self-reactive clones. Through the model of pRD, we reveal a RAG-dependent ‘domino effect’ that impacts stringency of tolerance and B cell fate in the periphery.

Created: 18. 1. 2023 / Modified: 11. 7. 2023 / Mgr. Stanislava Lindenthalová