TNF and infection: Indeed, mice deficient for TNF expression in macrophages/neutrophils displayed early, transient susceptibility to M. tuberculosis but recruited activated TNF-producing T-cells and controlled chronic infection, whereas deficient TNF expression specifically in T-cells resulted in early control but enhanced susceptibility during chronic infection with increased pulmonary pathology, and TNF inactivation in both myeloid and T-cells rendered mice critically susceptible to infection, similar to TNF deficient mice [58].