Fig. 1: M1 alveolar macrophages can efficiently take up SARS-CoV-2.
From: Distinct uptake, amplification, and release of SARS-CoV-2 by M1 and M2 alveolar macrophages
a The primary AMs were polarized to M1 by IFN-γ (20 ng/mL) and LPS (100 ng/mL) or M2 by IL-4 (20 ng/mL) for 24 h, and then infected with SARS-CoV-2 at the ratio of 1:1 (TCID50: cells) for 2 h. Cells were fixed for RNAscope analysis with SARS-CoV-2-specific probes. Probe 1 targets viral positive-sense sequence to evaluate viral distribution (green color). Scale bar, 5 μm. b M1 or M2 AMs infected with SARS-CoV-2 for 30 min were stained with anti-NP and anti-Rab5 antibodies and observed under a confocal microscope. Scale bar, 5 μm. c M0, M1, or M2 AMs and primary alveolar epithelial (AT2) cells isolated from hACE2 mice were infected with SARS-CoV-2 for 5 min or 30 min and then fixed for RNAscope analysis. Scale bar, 5 μm. d Same as c, except that cells were stained with the anti-NP antibody. Scale bar, 5 μm. The data represent the mean ± SD of 3 independent experiments. *P < 0.05, ***P < 0.001, by one-way ANOVA (a, c, d).
