Stimulated by lipopolysaccharides (LPS), interferon-γ or tumor necrosis factor-α (TNF-α), M1 macrophages are characterized by high antigen presentation and expressions of pro-inflammatory cytokines [e.g., interleukin (IL)-1β, IL-6, and the cell membrane molecule CD86], playing an important role in host defense against infection (3). This evidence concerns the gene TNF and infection.