FIG. 7.

Immunofluorescence and histological analyses of WT, Wisp3^−/−, and WISP3^TG mice. (A to D) Immunofluorescence staining of elbow joint sections from 2-day-old WT, Wisp3^−/−, and WISP3^TG (TG) mice with polyclonal antibody W3-C. WISP3 protein was detected with a red fluorescence-labeled secondary antibody, while cell nuclei were stained blue with DAPI. No staining was seen with WT or Wisp3^−/− mice, while cartilage staining is apparent with WISP3^TG mice. Note that WISP3 protein is not detectable in noncartilagenous tissues in the joints of the WISP3^TG mice. (E and F) Comparison of toluidine blue-stained sagittal sections of 11.5-month-old WT and WISP3^TG knee joints revealed no obvious morphological or histological differences. F, femoral condyle; T, tibial plateau. Magnification, ×100 (A to C, E, and F); ×200 (D).