Loss of fibrin(ogen) restores macrophage migration in plasminogen-deficient mice. (A) FSC vs SSC plots for all genotypes represent all cell populations. Flow cytometry analysis of peritoneal lavage fluid at 72 hours after thioglycollate stimulation shows normalized recruitment of total hematopoietic cells (B) and macrophages (C) to the peritoneal cavity. The left panels in B and C are examples of flow cytometry of lavage fluid from individual mice. (D) Independent experiment analyzing cell accumulation in peritoneal lavage fluid at 72 hours after thioglycollate stimulation. Plg^−/−/Fib^+/+ mice exhibited the expected decrease in leukocyte migration. Plg^+/+/Fib^−/− mice had a significant increase in leukocyte migration after peritonitis induction. Deletion of both plasminogen and fibrinogen returned the phenotype to the wild-type migration pattern. (E) Examination of cytospins from the peritoneal lavage fluid confirmed that the total leukocyte count was driven by the predominant cell type, macrophages. Data are shown as individual values with means indicated. n.s., not significant.