Fig. 1: S1 proteins from two commercial sources, RayBiotech and AMSBIO, are transported across the mouse BBB.
From: The S1 protein of SARS-CoV-2 crosses the blood–brain barrier in mice
The brain/serum ratios of I-S1 from RayBiotech and AMSBIO and T-Alb that was co-injected with I-S1-RayBiotech or I-S1-AMSBIO are plotted against exposure time. The slopes of the lines represent the Ki value of each compound in μl g–1 min–1 (Methods). The y-axis intercept (Vi) of each compound reflects the vascular space in µl g–1. The Ki and Vi values (mean ± s.e.) were calculated by simple linear regression. The Ki for I-S1 (RayBiotech) was significantly non-zero (P < 0.0001), indicating that there was brain uptake. The Ki for I-S1 (AMSBIO) was also significantly non-zero (P < 0.0001). Statistical comparisons of I-S1 curves from each vendor showed no statistical difference between the Ki values (F(1,22) = 0.05881, P = 0.8106) but did show a difference between the Vi values (F(1,23) = 10.32, P = 0.0039). The Ki for T-Alb-R did not significantly deviate from zero (P = 0.3556), indicating that there was no brain uptake. The Ki value for T-Alb-A also did not significantly deviate from zero (P = 0.5792). The apparent lack of T-Alb brain uptake indicates that T-Alb remained confined to the vascular space and did not leak.
