Six weeks after resuming the antibiotictreatment, TNF KO mice rapidly lost weight, developed severe illness, and wereterminated at 11 weeks with lung bacterial loads of4 log10 CFU/lung higher than wild-type mice andsevere inflammation indicating M. tuberculosis infection reactivation.Similarly, TNFR1 KO mice degraded rapidly and had to be terminated on day 88post infection with high bacterial burden (5.6 log10CFU/lung) and inflammatory lung. This evidence concerns the gene TNF and infection.