Role of Interferon-γ-Producing Th1 Cells in a Murine Model of Type I Interferon-Independent Autoinflammation Resulting From DNase II Deficiency.

Abstract

OBJECTIVE:

Patients with hypomorphic mutations in DNase II develop a severe and debilitating autoinflammatory disease. This study was undertaken to compare the disease parameters in these patients to those in a murine model of DNase II deficiency, and to evaluate the role of specific nucleic acid sensors and identify the cell types responsible for driving the autoinflammatory response.

METHODS:

To avoid embryonic death, Dnase2-/- mice were intercrossed with mice that lacked the type I interferon (IFN) receptor (Ifnar-/- ). The hematologic changes and immune status of these mice were evaluated using complete blood cell counts, flow cytometry, serum cytokine enzyme-linked immunosorbent assays, and liver histology. Effector cell activity was determined by transferring T cells from Dnase2-/- × Ifnar-/- double-knockout (DKO) mice into Rag1-/- mice, and 4 weeks after cell transfer, induced changes were assessed in the recipient mice.

RESULTS:

In Dnase2-/- × Ifnar-/- DKO mice, many of the disease features found in DNase II-deficient patients were recapitulated, including cytopenia, extramedullary hematopoiesis, and liver fibrosis. Dnase2+/+ × Rag1-/- mice (n > 22) developed a hematologic disorder that was attributed to the transfer of an unusual IFNγ-producing T cell subset from the spleens of donor Dnase2-/- × Ifnar-/- DKO mice. Autoinflammation in this murine model did not depend on the stimulator of IFN genes (STING) pathway but was highly dependent on the chaperone protein Unc93B1.

CONCLUSION:

Dnase2-/- × Ifnar-/- DKO mice may be a valid model for exploring the innate and adaptive immune mechanisms responsible for the autoinflammation similar to that seen in DNASE2-hypomorphic patients. In this murine model, IFNγ is required for T cell activation and the development of clinical manifestations. The role of IFNγ in DNASE2-deficient patient populations remains to be determined, but the ability of Dnase2-/- mouse T cells to transfer disease to Rag1-/- mice suggests that T cells may be a relevant therapeutic target in patients with IFN-related systemic autoinflammatory diseases.

• Authors: Sudesh Pawaria, Kerstin Nündel, Kevin M Gao, Stephanie Moses, Patricia Busto, Kevin Holt, Rohit B Sharma, Michael A Brehm, Ellen M Gravallese, Merav Socolovsky, Anette Christ, Ann Marshak-Rothstein
• Journal: Arthritis & rheumatology (Hoboken, N.J.) (Arthritis Rheumatol) Vol. 72 Issue 2 Pg. 359-370 (02 2020) ISSN: 2326-5205 [Electronic] United States
• PMID: 31464028 (Publication Type: Journal Article, Research Support, N.I.H., Extramural)
• Copyright: © 2019, American College of Rheumatology.

Chemical References

• Interferon Type I
• Interferon-gamma
• Endodeoxyribonucleases
• deoxyribonuclease II

Topics

• Animals
• Autoimmune Diseases (etiology)
• Disease Models, Animal
• Endodeoxyribonucleases (deficiency)
• Inflammation (immunology)
• Interferon Type I
• Interferon-gamma (biosynthesis)
• Mice
• Mice, Inbred C57BL
• Th1 Cells (metabolism)