#4208 CRP EXACERBATES SARS-COV-2-NUCLEOCAPSID PROTEIN-INDUCED ACUTE KIDNEY INJURY

Abstract Background and Aims COVID-19, caused by severe acute respiratory syndrome coronavirus (SARS-CoV-2), is a progressive viral pneumonia with a broad spectrum of clinical manifestations involving multiple organs. Acute kidney injury (AKI) is common in COVID-19, especially the critically ill patients. Our previous study proved that kidney-specifically overexpressing SARS-CoV-2 N protein induces AKI, which become worsen in mice under ischemic condition. Clinically, CRP is a risk factor for AKI in COVID-19 patients. Recent clinical study showed that CRP Apheresis is able to effectively remove the plasma CRP and thus improve the clinical outcome in critically ill COVID-19 patients. We thus hypothesize that CRP may not only be a biomarker or risk factor, but also a potential mediator or novel therapeutic target for COVID-19 AKI. Method The role of CRP in COVID-19 AKI was investigated in a mouse model of AKI induced by ultrasound-microbubble-mediated kidney-specifically transferring SARS-CoV-2 N-expressing plasmids in CRP wide-type (WT) and Transgenic (Tg) mice. We also developed a novel therapy for SARS-CoV-2 N-induced by targeting CRP signaling with a neutralizing anti-CD32 antibody both in vivo and in vitro. Results In COVID-19 patients with AKI, serum levels of CRP were significantly elevated when compared with non-AKI group. In mice, kidney-specifically overexpressing SARS-CoV-2 N protein caused AKI including tubular necrosis and elevated levels of serum creatinine and BUN in CRP WT mice, which became more severe in CRP Tg mice. Importantly, targeting CRP-CD32 signaling with a neutralizing antibody to CD32 significantly inhibited SARS-CoV-2 N protein-induced AKI in CRP Tg mice. Mechanistically, we uncovered that CRP promoted SARS-CoV-2-N protein-induced AKI via the Smad3-p21-dependent G1 cell cycle arrest and NF-κB/p-p65-driven renal inflammation, which was blocked by anti-CD32 antibody in vivo and in vitro. Conclusion CRP is not only a biomarker or risk factor, but also a mediator in SARS-CoV-2 N protein-induced AKI. CRP signals through CD32 mediate SARS-CoV-2 N-induced AKI via mechanisms associated with the Smad3-p21-dependent G1 cell-cycle arrest and NF-κB/p-p65-driven renal inflammation. Targeting CRP-CD32 signaling may represent as a novel therapy for COVID-19-associated AKI.