CD4⁺ TSCMs in the Bone Marrow Assist in Maturation of Antibodies against Influenza in Mice

Figure 2

CD4⁺ TSCMs from the BM respond to blood-borne antigens in vivo. (a) Schematic diagram of adoptive transfer. (b, c) BM-resident TSCMs possess the capacity of rapidly acquiring effector functions in vivo. The 5 × 10⁵ subset of T cells from the BM of OT-II mice was adoptively transferred to CD45.1 mice, respectively. Recipients were immunized with 500 μg OVA in CFA and sacrificed after 3 days for further analysis. The T cell subsets were determined by the following FACS isolations: CD45.2⁺ CD4⁺ CD44^low CD62L^high CD122^low Sca-1^low for naïve T cells; CD45.2⁺ CD4⁺ CD44^low CD62L^high CD122^high Sca-1^high for TSCMs; CD45.2⁺ CD4⁺ CD44^high CD62L^high for TCMs. (b) Numbers in histograms represent the percentage of BrdU-positive cells in BM-resident naïve T cells, TCMs and TSCMs after OVA stimulation. (c) Intracellular cytokine staining of naïve T cells, TCMs and TSCMs in the BM. Numbers in histograms show the percentage of IFN-γ-expressing cells in the BM after OVA stimulation. Data are representative of three independent experiments (). Frequencies of BrdU⁺ (b) and IFN-γ⁺ cells (c) were shown as means ± SD, -test. , , and .

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