title: Tumor necrosis factor neutralization combined with chemotherapy enhances Mycobacterium tuberculosis clearance and reduces lung pathology.
abstract: Tuberculosis (TB) is a major health problem requiring sustained immunity to inhibit Mycobacterium tuberculosis growth and appropriate antimicrobial therapy to prevent dissemination and drug resistance. Cell-mediated immune responses to M. tuberculosis involve the activation of cytokines such as Tumor Necrosis Factor (TNF) which is critical for granuloma formation and host resistance against TB. TNF inhibition, used as therapy for the treatment of inflammatory diseases, disrupts granuloma allowing replication of mycobacteria which may increase the efficacy of TB chemotherapy. To test this hypothesis mice infected with M. tuberculosis were treated with isoniazid (INH) and rifampicin (RMP) in the presence or absence of Enbrel, a soluble TNF receptor antagonist during three phases of M. tuberculosis infection. Inhibition of TNF with Enbrel augmented the efficacy of TB chemotherapy as shown by enhanced mycobacterial clearance from the lung of acute and established infection as well as in chronically infected mice. Furthermore, TNF inhibition significantly reduced lung pathology as compared to TB chemotherapy alone. Therefore, the experimental data suggest that TB chemotherapy may be more effective in the presence of a TNF inhibitor, which may be relevant to eradicate mycobacteria during chronic M. tuberculosis infection or reactivation.
authors.affiliation: UMR7355, CNRS Orleans, France ; Experimental and Molecular Immunology and Neurogenetics, University of Orleans France.
authors.forename: Marie-Laure
authors.initials: ML
authors.lastname: Bourigault
authors.forename: Rachel
authors.initials: R
authors.lastname: Vacher
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Rose
authors.forename: Maria L
authors.initials: ML
authors.lastname: Olleros
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Janssens
authors.forename: Valerie Fj
authors.initials: VF
authors.lastname: Quesniaux
authors.forename: Irene
authors.initials: I
authors.lastname: Garcia
keywords: Mycobacterium tuberculosis; TNF inhibitors; chemotherapy; granulomas; isoniazid (INH); rifampicin (RMP); tumor necrosis factor (TNF)