Extended Data Fig. 8: ACE2-independent SARS-CoV-2 entry in myeloid cells may rely on its interaction with TLR1.
(a) Quantitative PCR with reverse transcription (RT-PCR) analysis of SARS-CoV-2 S and RdRp (NSP12) proteins in MDM cells with live SARS-CoV-2 or heat-inactivated SARS-CoV-2 infection at an MOI = 1 for indicated time points. (b) RT-PCR analysis of SARS-CoV-2 S and RdRp (NSP12) proteins in THP-1 cells with live SARS-CoV-2 or heat-inactivated SARS-CoV-2 infection at an MOI = 1 for indicated time points. (c) RT-PCR analysis of expression of inflammatory genes in THP-1 cells with live SARS-CoV-2 or heat-inactivated SARS-CoV-2 infection at an MOI = 1 for indicated time points. (d) RT-PCR analysis of SARS-CoV-2 S, RdRp (NSP12), and NSP1 proteins in mouse BMDM (Bone marrow-derived macrophage) with SARS-CoV-2 infection at an MOI = 1 for indicated time points. (e) HEK293T ACE2-/- cells were transfected with plasmids containing either a control empty vector (EV) or TLR1, followed by SARS-CoV-2 infection at MOI = 1 for indicated lengths of time and temperature. RT-PCR analysis was then performed to analyze the RNA of SARS-CoV-2 S and RdRp. (f) Lysates of HEK293T cells transfected with the plasmid for TLR1-Flag, together with the empty vector or expression vector of Strep-tagged SARS-CoV-2 structural proteins (E, M, N), were subjected to immunoprecipitation with anti-Strep beads and immunoblot analysis with anti-Flag. (g) Cell proliferation of THP-1 WT or TLR1-/- cells were continuously assessed by counting the cells using flow cytometry for five days. (h) Phase contrast micrographs show the morphology of THP-1 WT or TLR1-/- cells (Scale bars 100 μm). Data in (f) is the representative of multiple independent experiments, data in (a-e, g) are plotted as the mean ± SD (n = 3 independent samples). Statistical analyses were performed using two-way ANOVA followed by Sidak post-test (a-c).
