Fig.2 Treatment with KVX-053 reduces the SARS-CoV-2 subunit 1 spike protein (S1SP)-induced alveolar inflammation. K18-hACE2 mice, instilled with S1SP 400 µg/kg exhibit elevated leukocyte content (A), increased monocyte and neutrophil levels (B) and higher total protein concentration (C) in BALF, 72 h after instillation. Intraperitoneal injections with the PTP4A3 inhibitor, KVX-053, 10 mg/kg/day, reduced alveolar inflammation. Means ± SEM; n = 11-15 mice/group; *P < 0.05; ***P < 0.001; ****P < 0.0001 with one-way ANOVA followed by Tukey’s test. WBC, white blood cell(s); BALF, bronchoalveolar lavage fluid.