Figure 7.

Immunohistochemical detection of the a3 V-ATPase subunit in bone biopsies. A: The bone biopsy of a patient affected by ATP6i-independent osteopetrosis was used as positive control for reaction to the anti-a3 antiserum. The arrow shows a group of osteoclasts labeled with brownish color because of positive reaction to the antiserum revealed by a horseradish-conjugated secondary antibody. B: Bone biopsy of patient 3 showing a3-negative osteoclasts (arrows) counterstained with hematoxylin. Original magnifications, ×40.