Figure 10.

IL-1β is a key cytokine for splenic monocytopoiesis. (A) rtPCR of IL-1β mRNA expression in the spleen throughout the first week after MI (n = 6–7 per group; *, P < 0.05). IL-1β protein by ELISA in the spleen on day 6 after MI (n = 4 per group; *, P < 0.05). (B) Cultured spleen cells from WT and IL-1R^−/− mice colony forming capacity on day 6 after MI. Experiment was done in duplicates. (C) Enumeration after FCM analysis on day 6 after MI of splenic MDPs (left), BrdU⁺ Mo in the spleen (middle), and in the heart (right) of IL-1R^−/− mice compared with WT. Mean ± SEM (n = 5 per group; *, P < 0.05). (D) Setup of the experiment: Adoptive transfer of CD45.2⁺ GMPs into infarcted CD45.1⁺ mice 1 d after MI. Analysis was performed 5 d later, comparing the capacity of transferred cells to generate Mo in the presence (WT) or absence (IL-1^−/−) of the IL-1R. (E) Dot plots from spleens are gated on Mo, identified as CD11b⁺, lineage⁻, and CD11c⁻. Mean percentage ± SEM (n = 4 recipients per group). (F) Enumeration of CD45.2⁺ Mo in the spleens of CD45.1⁺ recipients 6 d after MI and 5 d after adoptive transfer. Mean ± SEM (n = 4 per group; *, P < 0.05).