Transient impedance changes in venous endothelial monolayers as a biological radiation dosimetry response

In March of 2011, a magnitude 9.0 earthquake and subsequent 14 meter high tsunami caused major damage to the Fukushima Daiichi nuclear power plant in Japan. The release of radiation, along with other uncontrolled releases elsewhere, revealed the necessity of a portable high throughput minimally invasive biological dosimetry modality. Immediate and early radiation effects on vasculature could be used as a dosimetry modality. To test whether non-coronary vasculature exhibited transient perturbation in barrier function, video microscopy studies and electric cell-substrate impedance sensing (ECIS) technology were used to probe very subtle changes in primary human vascular endothelium. In our studies, human umbilical vein endothelial cell (HUVEC) monolayers exhibited a transient, significant decrease (p = 0.017) in monolayer resistance three hours after irradiation with 5.0 Gy of γ rays. Radiation induced perturbations in HUVEC monolayer permeability are similar in magnitude and kinetics to those observed in coronary arterial endothelium. Therefore, at least two types of endothelia respond to radiation on ECIS arrays with an early transient disruption in permeability. This finding supports the use of early passage HUVECs for use in bioelectric dosimetry studies of vasculature and suggests that permeability changes in superficial vessels and sequellae could potentially serve as biological dosimetry tools.