Fig. 5: Effects of unlabeled S1, ACE2 and ACE2 substrates on I-S1 uptake into tissues.
From: The S1 protein of SARS-CoV-2 crosses the blood–brain barrier in mice
a–c, Tissue uptake of I-S1 from RayBiotech 10 min after i.v. injection with or without unlabeled S1 (from AMSBIO), ACE2 or the ACE2 substrates ghrelin or angiotensin II (Ang II). The y axis shows the albumin-corrected (delta) tissue/serum ratio. Data are the mean ± s.d. a, Unlabeled S1 at a dose of 0.1 μg (n = 10 mice), 1 μg (n = 10) or 10 μg (n = 9) did not reduce brain I-S1 uptake compared to vehicle controls (n = 10; one-way ANOVA: F(3,33) = 0.6312, P = 0.6). b. Co-injection had a significant main effect on brain I-S1 uptake (one-way ANOVA: F(3,29) = 4.7, P = 0.0073), with 1 µg of ACE2 increasing uptake (ACE2 versus vehicle: P = 0.0109; Dunnett’s multiple-comparisons test) but no effect of 1 µg ghrelin or 1 µg Ang II. (*P < 0.05; n = 8, 8, 9 and 8 for the vehicle, ghrelin, Ang II and ACE2 groups, respectively). c, Co-injection had a significant main effect on lung I-S1 uptake (one-way ANOVA: F(4,35) = 5.12, P = 0.0023), with significant effects of 1 µg of unlabeled S1 (P = 0.0372), 1 µg ghrelin (P = 0.0188) and 1 µg ACE2 (P = 0.0007), but no effects of 1 µg Ang II (P = 0.3511; all Dunnett’s test). *P < 0.05, **P < 0.01 and ***P < 0.001. n = 8, 8, 7, 9 and 8 for vehicle, S1, ghrelin, Ang II and ACE2, respectively. One outlier (201 µl g−1) in the ghrelin group was detected by a Grubbs test (α < 0.05) and excluded from analysis.
