Repression of the Aryl-hydrocarbon Receptor Prevents Oxidative Stress and Ferroptosis of Intestinal γδT Cells and Alleviates Systemic Lupus Erythematosus

Qiaolin Wang¹, Yutong Wu², Qianjin Lu¹ and Ming Zhao¹, ¹Hospital for Skin Diseases, Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing, China (People's Republic), ²Department of Dermatology, Hunan Key Laboratory of Medical Epigenomics, Second Xiangya Hospital, Central South University, Nanjing, China (People's Republic)

Meeting: ACR Convergence 2024

Keywords: autoimmune diseases, Systemic lupus erythematosus (SLE)

Session Information

Date: Monday, November 18, 2024

Title: Abstracts: SLE – Etiology & Pathogenesis

Session Type: Abstract Session

Session Time: 3:00PM-4:30PM

Background/Purpose: Dysregulation of intestinal γδT cells orchestrates the pathogenesis of various autoimmune disorders, however, its involvement in systemic lupus erythematosus (SLE) etiology remains elusive.

Methods: Employing single-cell sequencing, we delineated the landscape of intestinal γδT cells in SLE murine model, complemented by flow cytometry and in vivo and in vitro assays to corroborate the single-cell sequencing findings. Supplementation of selenium was administered to observe their impact on the oxidative stress of intestinal γδT cells, gut barrier and the development of SLE.

Results: Integration of single-cell sequencing with flow cytometry unveiled a significant reduction of intestinal γδT cells along with markedly decreased expression of tight junction proteins. Mechanistically, single-cell sequencing analysis revealed significantly decreased expression of aryl hydrocarbon receptor repressor (AHRR) in intestinal γδT cells, resulting in excessive activation of the aryl hydrocarbon receptor and subsequent oxidative stress and ferroptosis in intestinal γδT cells. Supplementation with selenium effectively suppressed oxidative stress-induced γδT loss, improved gut barrier, and significantly reduced levels of proteinuria and autoantibodies in SLE model, ultimately improving their survival.

Conclusion: Our investigation unveiled that excessive activation of the aryl hydrocarbon receptor (AHR) induces oxidative stress and ferroptosis, leading to γδT cell loss and subsequent gut barrier impairment in SLE model. The beneficial effects of antioxidant stress on improving gut barrier offer new insights for the treatment of SLE.

Figure 1. Significantly decreased epithelial γδT cells in the intestine of lupus. (A and B) Flow cytometry analyses were conducted in a supplementary group of 6 Mpj mice and 5 Lpr mice to examine γδT cell populations. Each dot denotes an individual mouse. (C) UMAP plot of γδT cells in intestinal epithelial layer. (D) Feature plots representing expression of Trdc, Cd8a, Cd8b1, Gzma, Gzmb, Tcf7, Stmn1, and Mki67. (E and F) UMAP plot of γδT subsets (E) and frequency of γδT subsets out of total γδT cells (F) in Mpj and Lpr mice. (G) Bubble diagrams display the Gene Ontology (GO) biological process (BP) terms that are enriched in total γδT cells of Mpj and Lpr mice. (H) Violin plot illustrating the expression of Ahrr and Uba52 in total γδT cells from Mpj and Lpr mice. Each dot represents one cell. (I) Ahrr and Cyp1b1 expression in ileal tissues of Mpj and Lpr mice analyzed by qPCR. (J) Quantification of C_11 BODIPY staining in γδT cells from Mpj and Lpr mice. (K) ZO_1 expression in ileal tissues of Mpj and Lpr mice analyzed by qPCR. Statistical significance in (B), (I), (J) and (K) was determined by student’s t-test. Each dot denotes an individual sample. *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001.

Figure 2. Dietary selenium supplementation rescues γδT loss and ameliorates the lupus symptoms in Lpr mice. (A) Lpr mice were administered drinking water supplemented with selenium at concentrations of 2 and 4 mg/L for 8 weeks, respectively. (B) Representative flow cytometry plots and quantification of γδT in CD3+T cells from Mpj and Lpr mice with and without dietary selenium supplementation. (C and D) Proteinuria (C) and anti-ANA (D) from Mpj and Lpr mice with and without dietary selenium supplementation. (E and F) Representative plot and quantification of ZO_1 expression based on immunohistochemical staining. (G) Representative plot and quantification of H&E staining, IgG and C3 deposition in the kidney. Statistical significance was determined by one-way ANOVA with dunnett post hoc test. Each dot denotes an individual mouse. *P < 0.05, **P < 0.01, ***P < 0.001.

Figure 3. IFN-γ contributed to the reduced expression of AHRR. (A) Inflammatory cytokines expression in ileal tissues of Mpj and Lpr mice analyzed by qPCR. (B) AHRR and CYP1B1 expression in Jurakt cell induced by different concentrations of IFN-γ. (C) Representative flow cytometry result and quantification of C_11 BODIPY staining in Jurkat cell induced by different concentrations of IFN-γ. Statistical significance in (A) was determined by student’s t-test and (B and C) was determined by a one-way ANOVA test with Dunnett’s multiple comparisons test. Each dot denotes an individual sample. *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001.

Disclosures: Q. Wang: None; Y. Wu: None; Q. Lu: None; M. Zhao: None.

To cite this abstract in AMA style:

Wang Q, Wu Y, Lu Q, Zhao M. Repression of the Aryl-hydrocarbon Receptor Prevents Oxidative Stress and Ferroptosis of Intestinal γδT Cells and Alleviates Systemic Lupus Erythematosus [abstract]. Arthritis Rheumatol. 2024; 76 (suppl 9). https://acrabstracts.org/abstract/repression-of-the-aryl-hydrocarbon-receptor-prevents-oxidative-stress-and-ferroptosis-of-intestinal-%ce%b3%ce%b4t-cells-and-alleviates-systemic-lupus-erythematosus/. Accessed .

« Back to ACR Convergence 2024

ACR Meeting Abstracts - https://acrabstracts.org/abstract/repression-of-the-aryl-hydrocarbon-receptor-prevents-oxidative-stress-and-ferroptosis-of-intestinal-%ce%b3%ce%b4t-cells-and-alleviates-systemic-lupus-erythematosus/