Figure 3.

SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) infection induces human lung microvascular endothelial cells (hLMVECs) pyroptosis coincident with activation of inflammatory NLPR3–CASP (NLR family pyrin domain containing 3-caspase)-1 signaling and IL (interleukin)-1β cleavage. hLMVECs were infected with increasing titers of SARS-CoV-2 (MOI [multiplicity of infection]: 0.01, 0.1, and 0.5) for 1 d. A, Phase-contrast micrographs of hLMVECs post–SARS-CoV-2 infection for 1 d. Scale bars, 200 µm. B, Cytotoxicity activity of SARS-CoV-2 infection was analyzed by LDH (lactate dehydrogenase) release. n=6/group. *P<0.05, **P<0.01, ****P<0.0001, 2-tailed unpaired t test. C, Western blot was performed with the indicated antibodies. Activation of inflammatory NLRP3–CASP-1 pyroptotic signaling and IL-1β cleavage were shown in the blots.