A blood RNA transcript signature for TB exposure in household contacts

We studied household contacts of TB patients; healthy volunteers without recent history of TB exposure; and patients with active TB. We performed whole-blood RNA sequencing (in all), an interferon gamma release assay (IGRA; in contacts and healthy controls) and PET/MRI lung scans (in contacts only). We evaluated differentially-expressed genes in household contacts, compared these to differentially-expressed genes seen in the active TB group and assessed the association of a composite gene expression score to independent exposure/treatment/immunological variables.