The Tween 80 Toxicity in Chicken Embryos and Effect on the Kinetics of Newcastle Disease Virus Replication

Background: Non-ionic surfactant, Tween-80 (TW80) is commonly used for drug delivery due to its effect on the cell membrane permeation. The change in permeability can also increase viral infectivity in cells. This study was undertaken to improve upon Newcastle disease virus (NDV) titer cultivated with embryonic chicken eggs. Methods: The toxicity of TW80 was investigated against chicken embryos at varying concentrations, and changes in the morphology and weights of the heart, liver, and spleen of 4-day old chicken embryos were analyzed. Also, the effect of non-toxic concentrations of TW80 was examined on the infectivity of NDV. The virus was titrated in the allantoic fluid, using a 50% embryo infectious dose (EID50). Results: At high concentrations of TW80, hemorrhage-induced mortality was observed in embryos at the early stages of incubation. The embryos’ viability was not affected at low TW80 concentrations, indicating that its toxicity to the chicken embryos was dose-dependent. The infectivity titer of NDV was increased in the presence of TW80 compared to those inoculated with NDV only. Conclusions: The data suggest that TW80 is toxic to chicken embryos at high concentrations, but it enhances cell membrane permeability for NDV particles at low concentrations without affecting the embryos’ viability.