Constitutive p40 promoter activation and IL-23 production in the terminal ileum mediated by dendritic cells
J. Clin. Invest. Christoph Becker, et al. 112:693 doi:10.1172/JCI17464 [Go to this article.]

Figure 5
IL-12 p40 is produced largely by CD11c⁺ DCs located below the crypts in the lamina propria. (a) Cryosections of transgenic mice were analyzed by immunohistochemistry for luciferase expression. One representative staining for luciferase in the small intestine (D4) of a transgenic animal out of four is shown (left panel). Luciferase-expressing cells were mainly seen in the lamina propria below the crypts (arrows). No staining was seen in sections from transgenic mice treated with an isotype control Ab right panel), the proximal segments of the small intestine (D1, D2), and in healthy nontransgenic control mice (not shown). (b) Detection of CD11c⁺ and CD11b⁺ cells in the lamina propria of transgenic mice. More CD11c⁺ than CD11b⁺ cells were detected in the lamina propria, suggesting that many cells in the lamina propria of healthy mice carry surface markers of DCs. No differences in the staining patterns of CD11b⁺ and CD11c⁺ cells were noted between the proximal and the distal segments of the small bowel. (c) IL-12 p40 cytokine levels in supernatants from CD11c⁺ enriched DCs and CD11c^–CD11b⁺ enriched macrophages isolated from the lamina propria of healthy mice. Lamina propria cells were isolated as described in Methods and purified using the MACS system. To measure IL-12 p40 protein production, 500,000 cells/well were seeded out in 1 ml culture medium in triplicate and incubated in the presence or absence of LPS/SAC. After 24 hours, supernatants were removed and assayed for p40 concentration by ELISA. Unstim, unstimulated.