Effects of IL-1α on the cells recovered from the pouch. An antigenic challenge was performed and recombinant murine IL-1α (5 μg/mouse) or PBS was injected into the air pouch of MGL1-deficient or wild-type mice on day 0. The cells in the pouch fluid were collected from wild-type mice that were treated with PBS (A-B) and MGL1-deficient mice treated with PBS (C-D) or with IL-1α (E-F) on day 3. To examine the effect of IL-1α, the expression of CD11b or CD45 on these cells was analyzed by flow cytometry (B,D,F). Flow cytometric scatter profiles of these cells are also shown (A,C,E). Open histograms in panels B, D, and F represent the staining with control mAb. The number of cells recovered from the pouch was counted and plotted in panel G. The number of cells in the pouch fluid obtained from MGL1-deficient mice was greater than that from wild-type mice or that from MGL1-deficient mice injected with IL-1α. Injection of IL-1α also reduced the number of CD11b-negative/CD45-negative subpopulations in the air pouch of MGL1-deficient mice to a level similar to that of wild-type mice. Similar data were obtained on day 4.