Fig. 4: tVLPs modulate antigen-specific CD4⁺ T cell responses by suppressing Tconv proliferation and enhancing Treg activation.
Spleen cells from DO11.10 x Foxp3-GFP transgenic mice were labeled with CellTraceTM Violet (CTV) and cultured for 3 days in the absence of exogenous IL-2 with 15 μg/mL of tVLPOVA, VLPOVA (OVA+ only), medium or VLP⁻ (no antigen, no CTLA-4) as controls. Foxp3⁻ (Tconv) and Foxp3⁺ (Treg) OVA-specific CD4⁺ T cells were then analyzed by flow cytometry. A Representative CTV dilution plots showing proliferation of CD44hi antigen-experienced Tconv and Treg cells (left panel). Quantification of proliferated (divided) cells is shown (right panel) as both percentages and absolute numbers. Data are means ± SEM; n = 6; **p < 0.01; Mann–Whitney test, and are representative of 3 independent experiments. B Relative expression of functional surface and intracellular markers in CD44hi Tconv and Treg subsets. Expression levels (MFI) are normalized to the highest value per marker and averaged across groups. C Cytokine profiling by Luminex of culture supernatants collected at day 3. Results are expressed as absolute concentrations (pg/mL). Mean ± SEM are shown; n = 6; *p < 0.05; **p < 0.01; Mann–Whitney test vs. VLPOVA.
