Figure 9.

Increased proliferative potential of lung ILC2s of Id1 and dKO mice. Sorted lung ILC2s (4,000 cells) from mice of indicated genotypes were cultured for 3 d in the presence of 10 ng/ml each of IL-2 and IL-7 ± 10 ng/ml IL-25 or 1 ng/ml IL-33. 400,000 CD45.1⁺ thymocytes were added as carriers at the time of the flow cytometry analyses, and counting beads were used to determine the CD45.2⁺ cell numbers. Based on the recovery of CD45.1⁺ cells, it was estimated that the intracellular staining procedures caused a 50% loss of the cells. (a and b) Cell counts (a) and percentages (b) of CD45.2⁺Ki67⁺ cells are shown (n = 3). Data shown are representatives from two to three independent experiments. Student’s t tests were used to determine the statistical significance between WT and mutant cells. Error bars are SEM. *, P < 0.05; **, P < 0.01; ***, P < 0.001; ****, P < 0.0001. (c) Representative intracellular staining profiles for Ki67 expression in lung ILC2s cultured in the indicated conditions. Data shown are representative graphs from two independent experiments. The solid peak shows the negative control for anti-Ki67 staining. Blue line, WT; orange line, Id1; cyan line, dKO. (d) Ki67 staining of freshly isolated lung ILC2s. Student’s t tests were used to determine the statistical significance. ns, not significant.