Evaluation of NFκB-dependent inflammatory responses induced by TNFα in 3D human microvessels

Endothelial inflammation underlies the development of cardiovascular complications. Recently, advances in three-dimensional (3D) in vitro models that recapitulate human microvessel functions have been increasingly described. However, the pathological mechanisms of endothelial cells (ECs) in 3D microvessels remain to be elucidated. Here, we examined the involvement of nuclear factor κB (NFκB) in vascular inflammation of 3D microvessels. Human umbilical vein ECs were cultured in a microfluidic device (OrganoPlate) under luminal flow. 3D microvessels were highly stable and exhibited tubular structures with low permeability to different sized macromolecules. Tumor necrosis factor (TNF) α stimulation increased vascular leakage, which was associated with disruption of VE-cadherin and F-actin. Moreover, marked induction of monocyte adhesion, VCAM-1, and IL-6 was observed following TNFα treatment in the 3D microvessels. These effects of TNFα were significantly abrogated by pretreatment of microvessels with NFκB inhibitor, BAY 11–7082. TNFα also increased nuclear translocation of NFκB p65 in endothelial tubes, which was partially blunted by BAY 11–7082. We concluded that NFκB signaling remained intact and drove the inflammatory responses to TNFα in 3D microvessels. Our study demonstrates the feasibility of using a 3D platform to investigate inflammation-related pathogenesis of microvasculature diseases in a more physiological context.