Mutations in topoisomerase IIβ result in a B cell immunodeficiency
- Nat Commun. 2019 Aug 13;10(1):3644. doi: 10.1038/s41467-019-11570-6.
- 1. Department of Pediatrics, University of California at San Diego, La Jolla, CA, 92093, USA. [email protected].
- 2. Rady Children's Hospital of San Diego, San Diego, CA, 92123, USA. [email protected].
- 3. Department of Pediatrics, University of California at San Diego, La Jolla, CA, 92093, USA.
- 4. Division of Genetics and Epidemiology, Institute of Cancer Research, London, SM2 5NG, UK.
- 5. Center for Applied Genomics, Children's Hospital of Philadelphia, Philadelphia, PA, 19104, USA.
- 6. Department of Medicine, University of California at San Diego, La Jolla, CA, 92093, USA.
- 7. Regeneron Pharmaceuticals, Inc., Tarrytown, NY, 10591, USA.
- 8. Laboratory of Molecular Immunology, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, 92093, USA.
- 9. Department of Pediatrics, Levine Children's Hospital, Atrium Health, Charlotte, NC, 28203, USA.
- 10. Department of Genetics, Children's Hospital of Philadelphia, Philadelphia, PA, 19104, USA.
- 11. Department of Pediatrics, University of Pennsylvania School of Medicine, Philadelphia, PA, 19104, USA.
- 12. Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK.
- 13. German Center for Pediatric and Adolescent Rheumatology, Garmisch-Partenkirchen, 82467, Germany.
- 14. Division of Neonatology, University Hospital for Children and Adolescents, University of Leipzig, Leipzig, 04109, Germany.
- 15. BGI-Shenzhen, Beishan Industrial Zone, Shenzhen, 518083, China.
- 16. China National GeneBank, BGI-Shenzhen, Jinsha Road, Shenzhen, 518120, China.
- 17. Rady Children's Hospital of San Diego, San Diego, CA, 92123, USA.
- 18. Institute for Genomic Medicine, University of California San Diego, La Jolla, CA, 92093, USA.
- 19. San Diego Branch, Ludwig Institute of Cancer Research, La Jolla, CA, 92093, USA.
B cell development is a highly regulated process involving multiple differentiation steps, yet many details regarding this pathway remain unknown. Sequencing of patients with B cell-restricted immunodeficiency reveals autosomal dominant mutations in TOP2B. TOP2B encodes a type II Topoisomerase, an essential gene required to alleviate topological stress during DNA replication and gene transcription, with no previously known role in B cell development. We use Saccharomyces cerevisiae, and knockin and knockout murine models, to demonstrate that patient mutations in TOP2B have a dominant negative effect on enzyme function, resulting in defective proliferation, survival of B-2 cells, causing a block in B cell development, and impair humoral function in response to immunization.