Figure 3. HBV exposure in utero induces a robust Th1-polarized response in the CB.

(a) CB mononuclear cells were stimulated overnight with phorbol myristate acetate (PMA)/ionomycin and the cytokine production by CD3⁺T cells was measured using intracellular cytokine staining. Dot plots show the percentages of cytokine-producing CD3⁺T cells from healthy (HC; n=6) or HBV-exposed (HBV; n=11) CB. Cytokine production by CD3⁺T cells from the peripheral blood of pediatric and young adult patients with chronic HBV (HBV; n=10) and age-matched healthy controls (HC; n=33) were included for comparison. Horizontal line represents the median. (b) Representative FACS dot plots of Th1 cytokine (TNF-α, IFN-γ and IL-2) production from healthy and HBV-exposed CB T cells after PMA/ionomycin stimulation. (c) Graphical representation of single-, double- and triple-producer Th1 cells and their respective percentages in mean±s.e.m. in HBV-exposed CB. (d) Percentage of T cells expressing the Th1 marker, T-bet, in CB of healthy (n=4) and HBV⁺ (n=4) mothers. P-values were calculated using Mann–Whitney test.*P<0.05.