Extended Data Fig. 4: Transport of S1 proteins across human iPSC-derived brain-like endothelial cell (iBEC) monolayers.
From: The S1 protein of SARS-CoV-2 crosses the blood–brain barrier in mice
a. RayBiotech I-S1 passage across the iBEC monolayer was not significantly faster than that of T-Alb (p = 0.1464, t = 1.527, df=16; two-tailed paired t-test). Combination of 3 independent differentiations, n = 17 transwells/group, average TEER (2578 ± 897.8 Ω*cm2). b. Transport of RayBiotech I-S1 in the presence of 5 µg/ml excess unlabeled S1. Excess S1 had no significant effect on I-S1 or T-Albumin Pe (p > 0.5; two-way ANOVA). N = 5-6 transwells/group from a single differentiation c. Transwells were treated with WGA (0.5 mg/ml) or vehicle. There was a significant overall effect of treatment (F (1, 9) = 9.435, p = 0.0133) and analyte (F (1, 9) = 6.949, p = 0.0271) on RayBiotech I-S1 or T-Alb transport (two-way ANOVA), but there were no significant effects of WGA on I-S1 or T-Alb Pe (Sidak’s multiple comparisons testing). N = 5-6 wells/group from a single differentiation. d. Comparison of RayBiotech I-S1 and AMSBIO I-S1 transport. T-Alb was included with each I-S1 and also compared to the I-S1. Two-way ANOVA showed differences between I-S1s from the two sources) (F(1,10) = 10.1, p = 0.0098], but not between analytes (T-Alb vs I-S1). Multiple comparisons using Sidak’s test showed a faster transport for RayBiotech I-S1 vs AMSBIO I-S1 (p = 0.0324). N = 6 wells/group from a single differentiation *p < 0.05.
