Fig. 4. T lymphocytes response in the spleen and lungs of SpiN-immunized mice.

The frequency of activated CD4⁺ T (a) and CD8⁺ T (b) lymphocytes was evaluated by measuring the expression of cell surface CD44, data are presented as mea ± SEM. c UMAP projection of FACS data, in which splenocytes were gated on either CD4⁺ T or CD8⁺ T cell populations. Staining with anti-CD62L, anti-CD44 and anti-IFN-γ was used to define IFNγ-producing naïve, central memory (Tcm), and effector/effector memory (Teff/em) T cells. The frequency of naïve, memory and effector CD4⁺ T and CD8⁺ T populations producing IFN-γ with or without stimulation with SpiN are shown in panels d and e respectively. f, g Imunophenotyping of the lungs from mice immunized or not. The cells were cultured with SpiN protein and characterized by flow cytometry as CD4⁺ CD69⁺ CD103⁺ (f, left panel), CD4⁺ CD69⁺ CD103⁺ IFN-γ⁺ (f, middle panel), CD4⁺ CD69⁺ CD103⁺ TNF⁺ (f, right panel), CD8⁺ CD69⁺ CD103⁺ (g, left panel), CD8⁺ CD69⁺ CD103⁺ IFN-γ⁺ (g, middle panel) and CD8⁺ CD69⁺ CD103⁺ TNF⁺ (g, right panel). Data are representative of two independent experiments, n = 3–4 mice/group. Statistical analysis was performed using two-sided Mann–Whitney. * P < 0.05 and ** P < 0.01.