Figure 4.

Inhibition of E-induced CXCL8 production by soluble recombinant TLR2 or by anti-TLR2 antibodies. (A) The HEK-TLR2 cell line was stimulated with the E protein (200 ng/mL) in the presence or absence of recombinant TLR2 (20 ng/mL), anti-TLR2 and anti-TLR4 antibodies or LPS-RS (10 µg/mL), and recombinant TLR2 (20 ng/mL) alone was used as a control. (B) HEK-TLR2 cells were stimulated with inactivated SARS-CoV-2 (0.5–5 µg/mL) in the presence of anti-TLR2 antibodies or their isotypes (10 µg/mL). After 20 h of treatment, the cell supernatant was collected and CXCL8 chemokine production in the cell supernatants was quantified by ELISA. Statistical significance comparing different groups is denoted with * for p < 0.05, ** for p < 0.01 and *** for p < 0.001, while ns means non-significant.