LDC and human LAM nodules express NG2. A: In vitro expression of NG2 in primary cultures human LDC determined by immunocytochemistry (top, left), Western blot (top, right), or flow cytometry (bottom, right). For comparison, expression of NG2 in normal PASM is also shown by Western blot (top, right) and flow cytometry (bottom, left). The shaded area in flow histogram represents isotype antibody; the line represents NG2 expression using specific antibody. B: Photomicrograph (original magnification, ×20; left) of human lung LAM nodules (arrow) stained for NG2, within otherwise normal appearing lung parenchyma. C: Image focuses on LAM cells (arrows) within the larger proliferative LAM nodule outlined by the box in B (original magnification, ×40). D and E: Image of LAM nodules from two separate patients, respectively (original magnification, ×100). F: Image of a LAM tissue nodule and surrounding normal lung stained with an isotype control antibody (original magnification, ×40). G: Image of unaffected lung tissue stained for NG2, from the same patient in B showing an airway and surrounding smooth muscle (indicated by the arrow) (original magnification, ×40).