Figure 2.

Two immunizations with HIV-1 Env m1Ψ-mRNA-LNPs elicit potent antigen-specific CD4⁺ T cell responses. Mice received i.d. immunizations of Luc or HIV Env m1Ψ-mRNA-LNPs at weeks 0 and 4. Splenocytes were stimulated with Env peptides 2 wk after the second immunization, and cytokine production by CD4⁺ T cells was assessed by flow cytometry. (A–C) Percentages of CD4⁺ T cells producing IFN-γ (A), TNF-α (B), and IL-2 (C) are shown. (D) Frequencies of combinations of cytokines produced by CD4⁺ T cells. n = 5–8 mice, and each symbol represents one animal. Experiments were repeated at least two times to achieve statistical significance. Error bars are SEM. Statistical analysis: (A–C) one-way ANOVA with Bonferroni correction, *, P < 0.05; (D) Student’s t test, *, P < 0.05 compared with Luc mRNA–immunized mice.