The mRNA levels of TNF-α (Fig. 5A), IFN-β (Fig. 5B), IP-10 (Fig. 5C) and RANTES (Fig. 5D) after 24 hours post-infection were significantly up-regulated by influenza H5N1 virus (483/97) when compared with the mock infected cells (with p<0.01 with TNF-α, p<0.05 with IFN-β, p<0.001 with IP-10 and p<0.01 with RANTES), H1N1 viruses infected cells (with p<0.05 in TNF-α and p<0.01 with IP-10), and the mouse adapted WSN/H1N1 virus (with p<0.01 with TNF-α and IP-10). Here, TNF is linked to infection.