Fig. 3: Expansion of vaccine-induced T cells after challenge infection in pregnant mice.

C57BL/6 female mice were immunized with empty plasmid or nano2/4, challenged with Tc at 21 days post 2nd vaccine dose, mated with males at 7 days post-infection, and euthanized at E12–17 gestation days. Non-mated, non-pregnant female mice were included as controls. Splenocytes were labeled with fluorophore-conjugated antibodies and analyzed by flow cytometry, as in Fig. 2. Percent frequencies of a CD4⁻CD8⁻, b CD4+CD8+T lymphocytes, and (c–l) CD4⁺ and (m–v) CD8⁺ T-cell subsets that exhibited Tnv (d, n), Tem (e, o), and Tcm (i, s) phenotypes and produced IFNγ (f, j, p, t), PRF1 (g, k, q, u) and GZB (h, l, r, v) molecules are shown. Each mouse value is presented by a triangle and mean ± SEM values derived from duplicate observations per sample are plotted. Number of females: C (n = 8), Tc (n = 12), VaTc (n = 13), P (n = 6), TcP (n = 10), VaTcP (n = 6). Significance was calculated by Students’ unpaired t-test with or without Welch’s correction or Mann–Whitney U-test and p-values of <0.05, <0.01, <0.001, and <0.0001 are annotated with one, two, three, and four symbols, respectively. The horizontal bar indicates the compared groups. Detailed data are presented in Supplementary Table 4.