FIGURE 6.

CD4⁺ T cells primed for 3 days in B cell sufficient donors are capable of affecting clearance of PC in adoptive Rag−/− hosts. Donor wild type BALB/c or B cell-deficient Jh^−/− mice were infected with PC and CD4⁺ T cells were isolated from the draining TBLN at 3 or 14 days post-infection. T cells were adoptively transferred into Rag−/− recipients followed by infection with PC nuclei 4 days later. T cells were identified by CD4, CD44, and CD62L staining using flow cytometry, with the number of activated CD4⁺ T cells (CD44^hiCD62L^lo) depicted over time in the (A) lung digest, (B) BALF, and (C) TBLN. (D) PC lung burden was assessed in lung digest samples and expressed as Log₁₀ PC organisms per lung. Data are presented as mean ± SD for groups of 4 mice per timepoint per group and representative of 3 replicated experiments. Statistical significance defined at a p-value of < 0.05 for data generated in the Jh^−/− recipients compared to recipients of T cells from WT mice at each timepoint (*).