Figure 4.

Double immunofluoresence staining for Angptl2 and cellular lineage markers. A: The coexpression of Angptl2 with vimentin, synoviolin, or CD68 in the lining cell layer with from a patient with RA. Angptl2 is expressed in fibroblast-like synoviocytes (vimentin⁺ cells and synoviolin⁺ cells) and macrophage-like synoviocytes (CD68⁺ cells). B: The coexpression in the lymphatic follicle from a patient with RA of Angptl2 with vimentin, synoviolin, MAC2, CD3, or CD20. Angptl2 is also expressed in fibroblast-like synoviocytes (vimentin⁺ and synoviolin⁺ cells) and macrophage-like synoviocytes (MAC2⁺ cells), but not in T (CD3⁺) or B (CD20⁺) cells. Representative expression patterns derived from three independent RA patients are shown. IgG indicates isotype IgG control; PBS, second antibody only. Scale bars = 20 μm in all panels.