FIG. 2.

Exposure of the lungs to VLPs promotes the expansion, and alters the trafficking of influenza-specific CD4⁺ T cells. 1.2×10⁷ naïve CFSE-labeled influenza-transgenic CD4⁺ T cells from Thy1.2⁺ HNT mice²⁷ were transferred i.v. into Thy1.1⁺ recipients who had been exposed to VLPs or DPBS i.n. Recipient mice were rested for 24 h post-transfer, then infected with 1.5×10³ pfu PR8. At days 0, 3, 5, and 7 post-infection, one group was killed and CD4⁺Thy1.2⁺CD44^hiCFSE^lo donor T cells were quantified by FACS and total cell counts from microdissected iBALT (A), TBLNs (B), BAL (C), and spleen (D). Lymphocytes were gated by forward and side scatter plots. CD4⁺Thy1.2⁺ T cells were then examined for their expression of CFSE and CD44. Total CD4⁺Thy1.2⁺CD44⁺CFSE^lo T cells are shown. Each experiment was independently repeated at least twice with n=5 per group. A t-test was utilized to determine statistical significance at each timepoint. *p<0.05, **p<0.01, ***p<0.001, ****p<0.0001.