Single cell transcriptomics of impact of HIV on latent TB infection in a rhesus macaque model of Mtb/SIV co-infection [scRNA-seq cART+3HP]
We studied components of TB immunity that remain impaired after cART in the lung compartment, versus those that are restored by concurrent 3 months of once weekly isoniazid and rifapentine (3HP) and cART in the rhesus macaque (RM) model of LTBI and Simian Immunodeficiency Virus (SIV) co-infection. Concurrent administration of cART+3HP did improve clinical and microbiological attributes of Mtb/SIV co-infection compared to cART-naïve or -untreated RMs. While RMs in the cART+3HP group exhibited significantly lower granuloma volumes after treatment, they, however, continued to harbor caseous granulomas with increased FDG uptake. cART only partially restores the constitution of CD4+ T cells to the lung compartment in co-infected macaques. Concurrent therapy did not further enhance the frequency of reconstituted CD4+ T cells in BAL and lung of Mtb/SIV co-infected RMs compared to cART, and treated animals continued to display incomplete reconstitution to the lung. Furthermore, the reconstituted CD4+ T cells in BAL and lung of cART+3HP treated RMs exhibited an increased frequencies of activated, exhausted and inflamed phenotype compared to LTBI RMs. cART+3HP failed to restore the effector memory CD4+ T cell population that was significantly reduced in pulmonary compartment post SIV co-infection. Concurrent therapy was associated with the induction of Type I IFN transcriptional signatures and led to increased Mtb-specific TH1/TH17 responses correlated with protection, but decreased Mtb-specific TNF? responses, which could have a detrimental impact on long term protection. Overall design: These cells were isolated from bronchoalveolar lavage of rhesus macaques co-infected with Mtb/SIV and treated with cART+3HP