A, Representative picture of a mBSA-injected Wt mouse knee joint showing a
severe inflammatory infiltrate (between arrows), in contrast to a mBSA-injected
Nik−/− knee joint showing a reduced inflammatory infiltrate and
intact cartilage (between arrows; scale bar 500 μm). Sagittal sections of knee
joint with H&E staining and CD31 or CXCL12 IHC staining (insets; scale bars 100
μm). B, Quantification of the total number of synovial blood vessels
in Wt and Nik−/− mice. C, Quantification of
CXCL12+ blood vessels in synovial tissue of Wt and
Nik−/− mice. D, Quantification of synovial
inflammation on a semiquantitative scale of 0 to 4. E, Representative
pictures of tibial sections from Wt and Nik−/− mice, with B16
melanoma tumor tissue in trabecular bone. H&E-stained sections of tibias show marrow
replacement by tumor cells beneath the growth plate (scale bar 500 μm), and insets
show CD31 and CXCL12 IHC staining on tumor tissue (scale bar insets, 100 μm).
F, Quantification of the total number of blood vessels in melanoma tumor
tissue in Wt and Nik−/− mice. G, Quantification of
CXCL12+ blood vessels in melanoma tumor tissue of Wt and
Nik−/− mice. Panels A-D: n=5 per group; Panels E-G: n=6 per
group. Panels B-D,F,G represent mean±SEM *<P0.05, **P<0.001.