The effect of H. pylori infection on TNF-α expression was further investigated using real-time PCR and Elisa, and the detection revealed that infection with 26695 or Tx30a for 12 hours may have led to both more expression of TNF-α mRNA (P < 0.01, respectively) and more secretion of TNF-α protein into the culture supernatant (P < 0.01, respectively) in MKN45 and HGC27 cells (Figure 2C, D). This evidence concerns the gene TNF and infection.