IL6 and infection: As shown in Figure 3, we observed that 10 dyn/cm2 shear stress elicited varied responses in the four cytokines: (a) TNF-α level was undetectable, indicating there was no new TNF-α released after 16 h of infection due to shear stimulation; (b) IL-1β and IL-8 was modestly upregulated due to shear stress at 30 min, but this difference became insignificant at 3 h; and (c) IL-6 level was upregulated due to shear stress by more than 100% at 3 h, but not within 30 min, post-shear.