Human postmortem studies reveal tissue-specific differences amongst TB-patient groups

Abstract

If we are to break new grounds in TB research, we need to have a complete understanding of what is occurring at the site of infection in humans. Postmortem studies give us an opportunity compare involved and uninvolved tissues, in diseased and non-diseased tissues within the same individual. We examined the feasibility of carrying out a postmortem study in Mulago and Kiruddu National Referral Hospitals in Uganda, to determine whether we could use immune cells collected postmortem for immunological studies. We report that we can consent the Next-of-Kin, perform postmortem procedures and process tissues within 8 hours. Immune cells remain viable and functional up to 14 hours after death. We found subtle differences in T cell subsets within TB groups. Depletion of CD4 CD69+CD103+ depletion in lungs and BAL which is associated with HIV whereas CD8 CD69+CD103- depletion in BAL was associated with TB. Our data show overall changes Tissue Resident Memory T cells within, and between, TB-infected and TB-uninfected human lungs.