Abstract: FR-PO1219
Type 1 Interferon Signaling Inhibition Blocks Effects of Indoxyl Sulphate Exacerbation of Glomerular Endothelial Cell Injury In Vitro
Session Information
- CKD: Mechanisms - 2
October 25, 2024 | Location: Exhibit Hall, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: CKD (Non-Dialysis)
- 2303 CKD (Non-Dialysis): Mechanisms
Authors
- Seth, Asha, AstraZeneca PLC, Cambridge, Cambridgeshire, United Kingdom
- Stone, Heena S., AstraZeneca PLC, Cambridge, Cambridgeshire, United Kingdom
- Nanda, Sambit K., AstraZeneca US, Gaithersburg, Maryland, United States
- Lindholm, Catharina, AstraZeneca Swe, Gothenburg, Sweden
- Ferrari, Nicola, AstraZeneca PLC, Cambridge, Cambridgeshire, United Kingdom
- Woollard, Kevin, AstraZeneca PLC, Cambridge, Cambridgeshire, United Kingdom
Background
High levels of uremic toxins, including indoxyl sulphate (IS), are associated with poor outcomes in chronic kidney disease. Previous work by us has shown anifrolumab, a type I IFN receptor mAb approved for the treatment of moderate to severe systemic lupus erythematosus (SLE), reduces the levels of IS in patients with lupus nephritis (LN). To explore the mechanisms through which anifrolumab treatment and IS reduction may provide benefit in kidney disease we examined if IS has direct damaging effects on renal cells and explored whether interferon signalling is mediating these effects.
Methods
We used an in vitro model of human primary glomerular endothelial cells (HGECs) to investigate the effects of IS treatment on the activation of inflammatory signaling and markers of endothelial dysfunction (IL-1A, IL-6, IL-8 VCAM1, ICAM1) and on the induction of an interferon response (IFI27, RASD2). We first challenged the cells with LPS to prime the cells and mimic the increased vascular permeability that is seen in kidney disease. In further studies cells were treated with anifrolumab or human IgG1 isotype control, prior to the LPS and IS treatment. Cell lysates and supernatants were then collected for RNA and protein analysis respectively.
Results
Treatment of HGECs with IS significantly exacerbated the induction of the inflammatory markers IL-6, IL1A, and CXCL8 and the vascular dysfunction markers VCAM1 and ICAM1 caused by LPS priming. The treatment of the cells with IS alone had no effect on the markers assessed. The expression of type I IFN-responsive IFI27 and RASD2 genes following treatment with LPS was increased and no additional effects were seen when IS was added. The addition of anifrolumab prior to stimulation reduced IS mediated increases in injury and inflammation markers. In addition, anifrolumab prevented the increase in the type I IFN-response genes IFI27 and RASD2 in response to LPS treatment.
Conclusion
This study shows IS has a direct damaging effect on glomerular endothelial cells and this is mediated by type I IFN signalling. This mechanism may in part account for the link observed between increased IS levels and poor prognosis in CKD.
Funding
- Commercial Support – AstraZeneca