Objective In order to refine new therapeutic strategies in the pipeline for HBV cure, evaluation of virological and immunological changes compartmentalised at the site of infection will be required. We therefore investigated if liver fine needle aspirates (FNAs) could comprehensively sample the local immune landscape in parallel with viable hepatocytes. Design Matched blood, liver biopsy and FNAs from 28 patients with HBV and 15 without viral infection were analysed using 16-colour multiparameter flow cytometry. Results The proportion of CD4 T, CD8 T, Mucosal Associated Invariant T cell (MAIT), Natural Killer (NK) and B cells identified by FNA correlated with that in liver biopsies from the same donors. Populations of Programmed Death-1 (PD-1)hi CD39hi tissue-resident memory CD8 T cells (CD69+ CD103+) and liver-resident NK cells (CXCR6+ T-betlo Eomeshi), were identified by both FNA and liver biopsy, and not seen in the blood. Crucially, HBV-specific T cells could be identified by FNAs at similar frequencies to biopsies and enriched compared with blood. FNAs could simultaneously identify populations of myeloid cells and live hepatocytes expressing albumin, Scavenger Receptor class B type 1 (SR-B1), Programmed Death-Ligand 1 (PD-L1), whereas hepatocytes were poorly viable after the processing required for liver biopsies. Conclusion We demonstrate for the first time that FNAs identify a range of intrahepatic immune cells including locally resident sentinel HBV-specific T cells and NK cells, together with PD-L1-expressing hepatocytes. In addition, we provide a scoring tool to estimate the extent to which an individual FNA has reliably sampled intrahepatic populations rather than contaminating blood. The broad profiling achieved by this less invasive, rapid technique makes it suitable for longitudinal monitoring of the liver to optimise new therapies for HBV.
Bibliographical noteFunding Information:
Funding this work was supported by a Wellcome trust clinical research training Fellowship (107389/Z/15/Z) awarded to USg, a Barts and the london charity Project grant (723/1795) and an niHr research for patient benefit award (PB-Pg-0614-34087) to PtFK, a Medical research council grant (g0801213) and a Wellcome trust Senior investigator award and enhancement (101849/Z/13/a) to MKM.
This work was supported by a Wellcome Trust Clinical Research Training Fellowship (107389/Z/15/Z) awarded to USG, a Barts and The London Charity Project Grant (723/1795) and an NIHR Research for patient benefit award (PB-PG-0614-34087) to PTFK, a Medical Research Council grant (G0801213) and a Wellcome Trust Senior Investigator Award and Enhancement (101849/Z/13/A) to MKM.
© Author(s) (or their employer(s)) 2019.
- HBV-specific T cells
- fine needle aspirate
- hepatitis B virus
- intrahepatic-immune monitoring
- liver biopsy
- tissue-resident immunity