TLR7 gain-of-function genetic variation causes human lupus
- Nature. 2022 May;605(7909):349-356. doi: 10.1038/s41586-022-04642-z.
- 1. Centre for Personalised Immunology, Department of Immunology and Infectious Disease, John Curtin School of Medical Research, Australian National University, Canberra, Australian Capital Territory, Australia.
- 2. Research School of Biology, Australian National University, Canberra, Australian Capital Territory, Australia.
- 3. China Australia Centre for Personalised Immunology, Shanghai Renji Hospital, Shanghai Jiaotong University, Shanghai, China.
- 4. Centre for Tropical Bioinformatics and Molecular Biology, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, Queensland, Australia.
- 5. Centre for Cancer Biology, SA Pathology and the University of South Australia, Adelaide, South Australia, Australia.
- 6. Division of Structural Biology, Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia.
- 7. Sección de Nefrología, Hospital Infantil Universitario Niño Jesús, Madrid, Spain.
- 8. Unidad de Terapias Avanzadas, Oncología, Hospital Infantil Universitario Niño Jesús, Madrid, Spain.
- 9. Fundación de Investigación Biomédica, Hospital Infantil Universitario Niño Jesús, Madrid, Spain.
- 10. Unidad de Reumatología, Hospital del Niño Jesus, Madrid, Spain.
- 11. Department of Pediatrics, Drukier Institute for Children's Health, Weill Cornell Medical College, New York, NY, USA.
- 12. Seaver Autism Center for Research and Treatment, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
- 13. Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
- 14. Division of Child Neurology, Weill Cornell Medical College, New York-Presbyterian Hospital, New York, NY, USA.
- 15. Division of Pediatric Neurology and Developmental Neuroscience, Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA.
- 16. Texas Children's Hospital, Houston, TX, USA.
- 17. Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA.
- 18. Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX, USA.
- 19. Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA.
- 20. Shanghai Institute of Rheumatology, Renji Hospital, School of Medicine, Shanghai, Jiao Tong University (SJTUSM), Shanghai, China.
- 21. Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical Research, Clayton, Victoria, Australia.
- 22. Department of Molecular and Translational Science, Monash University, Clayton, Victoria, Australia.
- 23. Department of Renal Medicine, The Canberra Hospital, Canberra, Australian Capital Territory, Australia.
- 24. Department of Anatomical Pathology, The Canberra Hospital, Canberra, Australian Capital Territory, Australia.
- 25. Center for Autoimmune Genomics and Etiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA.
- 26. Departamento de Pediatría. Facultad de Medicina, Universidad Autónoma de Madrid (UAM), Madrid, Spain.
- 27. Centre for Personalised Immunology, Department of Immunology and Infectious Disease, John Curtin School of Medical Research, Australian National University, Canberra, Australian Capital Territory, Australia. [email protected].
- 28. Centre for Cancer Biology, SA Pathology and the University of South Australia, Adelaide, South Australia, Australia. [email protected].
- 29. Francis Crick Institute, London, UK. [email protected].
- # Contributed equally.
Although circumstantial evidence supports enhanced Toll-like Receptor 7 (TLR7) signalling as a mechanism of human systemic autoimmune disease1-7, evidence of lupus-causing TLR7 gene variants is lacking. Here we describe human systemic lupus erythematosus caused by a TLR7 gain-of-function variant. TLR7 is a sensor of viral RNA8,9 and binds to guanosine10-12. We identified a de novo, previously undescribed missense TLR7Y264H variant in a child with severe lupus and additional variants in Other patients with lupus. The TLR7Y264H variant selectively increased sensing of guanosine and 2',3'-cGMP10-12, and was sufficient to cause lupus when introduced into mice. We show that enhanced TLR7 signalling drives aberrant survival of B cell receptor (BCR)-activated B cells, and in a cell-intrinsic manner, accumulation of CD11c+ age-associated B cells and germinal centre B cells. Follicular and extrafollicular helper T cells were also increased but these phenotypes were cell-extrinsic. Deficiency of MyD88 (an adaptor protein downstream of TLR7) rescued autoimmunity, aberrant B cell survival, and all cellular and serological phenotypes. Despite prominent spontaneous germinal-centre formation in TLR7Y264H mice, autoimmunity was not ameliorated by germinal-centre deficiency, suggesting an extrafollicular origin of pathogenic B cells. We establish the importance of TLR7 and guanosine-containing self-ligands for human lupus pathogenesis, which paves the way for therapeutic TLR7 or MyD88 inhibition.