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

Figure 1

CD4⁺ memory stem cells preferentially reside in BM. (a) Expression of CD122 and Sca-1 in SP- and BM-resident naïve-like T cell compartment. Iridescent cloud represents the frequencies of CD122^high Sca-1^high subset gated on CD3⁺ CD4⁺ CD8⁻ CD44^low CD62L^high cells. Data are representative of six independent experiments. (b) TSCMs in various organs. The frequencies of TSCMs accounting for CD44^low CD62L^high CD4⁺ T cells in the peripheral blood (PB), lymph node (LN), spleen (SP), and bone marrow (BM) were shown as means ± SD, one-way ANOVA. . Data are representative of four independent experiments. (c) Expression of Bcl-2 in naïve and TSCMs subsets in BM-resident T cells. Overlaid histogram plots show the levels of Bcl-2 in BM-resident CD122^low Sca-1^low, CD122^low Sca-1^high, CD122^high Sca-1^low, and CD122^high Sca-1^high subsets gated on CD3⁺ CD4⁺ CD8⁻ CD44^low CD62L^high cells. Data are representative of five independent experiments. The MFI of Bcl-2 in CD122^low Sca-1^low, CD122^low Sca-1^high, CD122^high Sca-1^low, and CD122^high Sca-1^high subsets was shown as means ± SD, one-way ANOVA. . (d) Flow cytometric analysis of BM-resident TSCMs overlaid with SP- and BM-resident naïve T cells. Overlaid histogram lines show expression levels of a given molecule in different CD4⁺ T cell subsets. CD4⁺ T cell subsets were defined as follows: BM-resident TSCMs, CD3⁺ CD4⁺ CD8⁻ CD44^low CD62L^high CD122^high Sca-1^high; BM- and SP-resident naïve T cells, CD3⁺ CD4⁺ CD8⁻ CD44^low CD62L^high CD122^low Sca-1^low. Data are representative of five independent experiments. (e) qRT-PCR results show the expressions of CD44, Sca-1, β-catenin, Klf-7, Tcf-7, and Lef-1 in different CD4⁺ T cell subsets. CD4⁺ T cell subsets were defined as follows: BM-resident TSCMs, CD3⁺ CD4⁺ CD8⁻ CD44^low CD62L^high CD122^high Sca-1^high; BM- and SP-resident naïve T cells, CD3⁺ CD4⁺ CD8⁻ CD44^low CD62L^high CD122^low Sca-1^low. Data are representative of 3 independent experiments () and shown as means ± SD, one-way ANOVA. , , and .

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