Fig. 6. IL-6 is an in vivo T cell survival factor.

(A) Spleen T cell numbers in aged IgH^KO and IgH^KOIL6^Tg mice. Data show the mean +/− SEM from ten IgH^KO and nine IgH^KOIL6^Tg mice.

(B) Spleen NKT cell numbers in aged IgH^KO and IgH^KOIL6^Tg mice. Data show the mean +/− SEM from six IgH^KO and seven IgH^KOIL6^Tg mice.

(C) TREC copy numbers in IgH^KO and IgH^KOIL6^Tg T cells. TREC copy numbers were determined relative to TREC numbers in IgH^KO T cells, which was set to 100. Results show the mean +/− SEM of three independent experiments.

(D) Naïve and memory phenotype T cells in aged IgH^KO and IgH^KOIL6^Tg mice. CD62L, CD122 and CD44 expression were determined on gated CD4 and CD8 T cells of aged (37–52 weeks) mice. Data are representative of eight independent experiments with eight IgH^KO and eleven IgH^KOIL6^Tg mice.

(E) Pro-survival factor expression in IgH^KOIL6^Tg T cells. mRNA content of the indicated genes were assessed in purified IgH^KO and IgH^KOIL6^Tg CD4 T cells by RT-qPCR. Data show the mean +/− SEM of five independent experiments with a total of six IgH^KO and six IgH^KOIL6^Tg mice.