Single Systemic Transfer Of A Human Gene Associated With Exceptional Longevity Halts The Progression Of Atherosclerosis And Inflammation In Apoe Knockout Mice Through A Cxcr4-Mediated Mechanism

Aims Here, we aimed to determine the therapeutic effect of longevity-associated variant (LAV)-BPIFB4 gene therapy on atherosclerosis.Methods and results ApoE knockout mice (ApoE(-/-)) fed a high-fat diet were randomly allocated to receive LAV-BPIFB4, wild-type (VN1)-8P1F84, or empty vector via adeno-associated viral vector injection. The primary endpoints of the study were to assess (i) vascular reactivity and (ii) atherosclerotic disease severity, by Echo-Doppler imaging, histology and ultrastructural analysis. Moreover, we assessed the capacity of the LAV-BPIFB4 protein to shift monocyte-derived macrophages of atherosclerotic mice and patients towards an anti-inflammatory phenotype. LAV-BPIFB4 gene therapy rescued endothelial function of mesenteric and femoral arteries from ApaE(-/-) mice; this effect was blunted by AMD3100, a CXC chemokine receptor type 4 (CXCR4) inhibitor. LAV-BPIF84-treated mice showed a CXCR4mediated shift in the balance between Ly6C(high)/Ly6C(low) monocytes and M2/M1 macrophages, along with decreased T cell proliferation and elevated circulating levels of interteukins IL-23 and IL-27. In vitro conditioning with LAV-BPIFB4 protein of macrophages from atherosclerotic patients resulted in a CXCR4-dependent M2 polarization phenotype. Furthermore, LAV-BPIFB4 treatment of arteries explanted from atherosclerotic patients increased the release of atheroprotective IL-33, while inhibiting the release of pro-inflammatory IL-1 beta, inducing endothelial nitric oxide synthase phosphorylation and restoring endothelial function. Finally, significantly lower plasma BPIFB4 was detected in patients with pathological carotid stenosis (>25%) and intima media thickness >2mm.Conclusion Transfer of the LAV of BPIFB4 reduces the atherogenic process and skews macrophages towards an M2-resolving phenotype through modulation of CXCR4, thus opening up novel therapeutic possibilities in cardiovascular disease.