Our results could also see significant changes in immunogenicity and virulence, but on the contrary, after a 15-year-period infection, the microevolved T. asahii strain BM1403 induced much lower expression of TNF-α by BMDC and had a much superior survival rate than the AS2.2174 strain, tending to “peacefully” coexist with the host. The gene discussed is TNF; the disease is infection.