Paw edema and monocyte infiltration are markedly reduced in Nogo-A/B^−/− mice. (A) Nogo-A/B^−/− mice displayed reduced paw edema formation (n = 6 per group) after intraplantar injection of carrageenan. PCR on mouse blood cells 6 weeks after bone marrow transplantation confirmed the engraftment of donor bone marrow. (B) Immunostaining for CD68, a monocyte/macrophage marker, in sections from WT and Nogo-A/B^−/− mice 72 hours after carrageenan injection. Nogo-A/B^−/− mice showed a reduction of CD68⁺ monocytes/macrophages in the paw compared with WT mice (as quantified in the graph). Bar = 100 μM. (C) Carrageenan-induced paw edema was induced in lethally irradiated WT and Nogo-A/B^−/− mice transplanted with bone marrow from WT mice (WT → WT; WT → Nogo-A/B^−/−) or Nogo-A/B^−/− mice (Nogo-A/B^−/− → WT; Nogo-A/B^−/− → Nogo-A/B^−/−) (n = 12 per group). (D) CD68 immunostaining of paw sections 72 hours after carrageenan injection in bone marrow–transplanted mice. Bar = 100 μM. The data shown represent the means ± SEM *P < .05; **P < .01, ***P < .001. Bar = 100 μm.