Immunological Biomarkers in Tuberculosis Management

It is a composite outcome. Evolution of the disease is defined by clinical status, radiological computed tomography evolution and negation of the mycobacterial culture of routine respiratory samples.

The biomarkers assessed are:

• a combination of IGRAs test (QuantiFERON-Gold Plus and HBHA); 2) a transcriptomic signature; 3) a protein signature; 4) a phenotypic signature (by implementing an immunomonitoring approach).

Measurement of gamma interferon responses induced by different conditions of ex-vivo stimulation of the blood sample by specific Mtb peptides. This biomarker will be confronted with the evolution of the evolution of the disease as defined in the primary outcome measure.

Qualitative and quantitative monitoring of the different subpopulations of immune cells (CD4 + T cells, CD8 +(cluster of differentiation 8) T cells, MAIT, Th1, Th2, Th1, Tfh, Treg, naive, effector and memory cells) during anti-tuberculosis treatment will be carried out. The analytical characteristics (sensitivity, specificity, VPN and VPP) of this immunomonitoring tool will be determined by comparing the abundance of different cellular phenotypes with the evolution of the disease as defined in the primary outcome measure.

A transcriptomic signature in plasma is a set of genes involved in the immune response specifically deregulated during the different stages of infection and disease progression.

This assessment will be made from blood samples. The transcriptomic signature composed of 16 genes will be evaluated during the anti-tuberculosis treatment and confronted with the evolution of the disease as defined in the primary outcome measure.

A protein signature is composed of cytokines and chemokines, also deregulated during the various stages of infection and progression of the disease.

This assessment will be made from blood samples. The protein signature composed of cytokines / chemokines of interest (ie IP-10, TNF-a (tumor necrosis factor - a), IL-1(interleukin - 1), IL-18, IL-12, CCL4, IL-2, IFN-g (interferon - g),…) will be evaluated during the anti-tuberculosis treatment and confronted with the evolution of the disease as defined in the primary outcome measure.

To determine the achievement of target concentrations of rifampicin the pharmacokinetic profile of rifampicin will be evaluate by a combination of parameters such as the area under the curve, maximum and minimum concentration, clearance, volume of distribution, modeled from three concentration measurements at each visit. (V2, V3 and V4).

To establish the rate of metabolic self-induction of rifampicin the pharmacokinetic profile of rifampicin will be evaluate by a combination of parameters such as the area under the curve, maximum and minimum concentration, clearance, volume of distribution, modeled from three concentration measurements at each visit. (V2, V3 and V4).