Fig. 1

Phenotypic characterization of cultured lymphocytes after exposure to HCV. Lymphoid cells from the same healthy donor were either exposed to medium alone (no plasma, NP), normal human plasma (NHP 1–3) or HCV inocula (CHC 1–3). Cells collected at the time points indicated (d.p.i.) were stained for CD3, CD4 and CD8 or with isotype controls and analysed by flow cytometry. a Graphical representation of flow cytometry data showing phenotype of T cells for each infection condition tested. CD4⁺ T cells (solid black bars) and CD8⁺ T cells (hatched bars) are displayed as percentage of total CD3⁺ T cells at 4 different time points. The detection of HCV RNA positive strand was shown for 1, 7 and 10 d.p.i. For HCV RNA positive strand detection, (+++) indicates >5,000 vge/μg RNA, (++) between 500 and 5,000 vge/μg RNA, (+) between 50 and 500 vge/μg RNA, and (+/−) below 50 vge/μg RNA. For negative strand detection, (+) indicates detection and (−) no detection of the strand. Boxes indicate cultures in which the CD4⁺ to CD8⁺ ratio was altered when compared to cultures exposed to NP or NHP. n.a.- not applicable, n.t.- not tested. b Determination of T cell phenotype in cell cultures exposed or not to HCV and cultured for 10 d.p.i. Using forward versus side scatter, lymphocytes (gate R1) were separated from cellular debris. Lymphocytes were sub-gated on Alexa-488-positive CD3 T cells (gate R2) for enumeration of CD4⁺ and CD8⁺ T cells by detecting APC-positive CD8⁺ T cells found in the lower right (LR) quadrant and PerCP-positive CD4⁺ T cells in the upper left (UL) quadrant. Numbers in the UL and LR quadrants indicate percentages of positive cells