SPP1 and tuberculosis: Novel therapies to improve TB treatment are necessary; in this context, combined therapy of antibiotics and adenoviral vectors (gene therapy) has been proved before to be efficient in our laboratory for other cytokines like IFN-γ [15], osteopontin [16] and GM-CSF [45], and for antimicrobial peptides like cathelicidin (LL37) and beta defensin-3 [46], confirming gene therapy as a tool for a faster improvement in experimental progressive TB.