Hepatic expansion of a virus-specific regulatory CD8⁺ T cell population in chronic hepatitis C virus infection
J. Clin. Invest. Daniele Accapezzato, et al. 113:963 doi:10.1172/JCI20515 [Go to this article.]

Figure 5
Concomitant hepatic expansions of virus-specific CCR7^– CTL subsets with inappropriate proinflammatory functions or regulatory phenotypes. (A) Representative tetramer⁺CD8⁺ LILs from HLA-A2.1⁺ patient 2 (see Table 3) expressing the membrane phenotype (CCR7^–) of effector cells and high perforin levels, but inappropriate IFN-γ production. In particular, LILs from patient 2 were subdivided in two parts. One part was stained intracellularly with TC-labeled mAb to CD8, the pool of PE-labeled HLA-A2.1⁺ tetramers expressing NS3_1073–1082, NS3_1406–1415, or NS4_1851–1859 (mix tetramer, Mix tetr.), and FITC-labeled anti-perforin. A second part, after being stained with primary rat mAb to CCR7, was stained with the secondary PE-conjugated goat anti-rat Ig and the pool of tetramers indicated above. Then, following stimulation or no stimulation with the corresponding peptides and APCs (autologous irradiated PBMCs) for 6 hours, cells were stained intracellularly with FITC-labeled mAb to IFN-γ. Dot plots are gated on tetramer⁺ cells. Results are expressed as percentage of cells. Similar results were obtained by studying the other patients tested (see Table 3) with the pool of tetramers indicated for each patient in Table 2. (B) Tetramer⁺CD8⁺ LILs isolated from each indicated patient producing poor IFN-γ but notable amounts of IL-10. LILs were stained with the mix tetramer (indicated for each patient in the Table 2), were left unstimulated or were stimulated with the corresponding peptides and autologous APCs for few hours, and were stained intracellularly with both FITC-labeled mAb to IFN-γ or to IL-10. IFN-γ or IL-10 was undetectable in unstimulated cultures in both experiments in A and B (data not shown).