Identification of HIV-1–Positive Macrophages in Atherosclerotic Plaques of HIV-Infected Subjects.

Single (A–D) and double (E and F) immunostaining of aortic wall segments.

(A) p24 staining. A low-magnification image showing the presence of p24⁺ cells in an area adjacent to the plaque lipid core. The scale bar represents 100 μm.

(B) Detail of (A). p24⁺ cells show a characteristic morphology of foam cells. The scale bar represents 10 μm.

(C) CD68 staining. CD68⁺ cells were identified in a parallel consecutive section to that shown in (A). The scale bar represents 100 μm.

(D) Negative control (staining with an irrelevant primary antibody). The scale bar represents 100 μm.

(E) Double immunostaining showing the co-localization of p24 (brown) with CD68 (rose). Immunostaining included a combination of a rabbit polyclonal anti-p24 antibody in the peroxidase–anti-peroxidase system with DAB chromogen yielding a brown reaction product, and a mouse monoclonal antibody to CD68 in the alkaline phosphatase–anti-alkaline phosphatase system with Fast Red chromogen, resulting in a rose precipitate. Counterstaining was with Mayer's hematoxylin. The scale bar represents 50 μm.

(F) A detail of (E). The scale bar represents 15 μm.