FIG 7.

Pretreatment with IL-2 Ab Cx prevents proliferation of activated CHIKV-specific CD4⁺ T cells in draining lymph nodes. WT mice (n = 5 per group) were infected s.c. with 10⁶ PFU CHIKV-SGP011 after treatment with PBS, IL-2 only, JES6-1 only, or IL-2 Ab Cx. Cells were isolated from draining pLN on 6 dpi. (A) Representative histogram illustrating CFSE dilution in stimulated T cells. Splenocytes from NI mice were depleted of CD4⁺ T cells and used as antigen-presenting cells (APCs). Enriched CD4⁺ T cells were depleted of Tregs, labeled with CFSE, and stimulated for 4 days with medium only, anti-CD3/CD28 Dynabeads, APCs only, or CHIKV-pulsed APCs. (B) Representative scatter plot (right) showing major histocompatibility complex class II (MHCII) and CD11c expression gated on total live CD45⁺ leukocytes from pLN. The boxed area corresponds to inflammatory DCs, which were further analyzed for CD80 expression, as shown in the histogram plot (middle). The bar chart (right) shows CD80 expression on inflammatory DCs. Statistical analysis was done using one-way ANOVA across all CHIKV-infected groups, followed by Dunnett's posttest comparing to the PBS-CHIKV group. Data are means and SD from two independent experiments. ***, P = 0.0007 (IL-2 Ab Cx CD80).