Detection of antibodies (Abs) specific to proteins derived from UT-7 cells in the sera of patients with AA. (A) Immunofluorescence analysis of UT-7 cells using 1:200 diluted sera and FITC-labeled anti–human IgG. (i-ii) Healthy persons; (iii-iv) patients with AA. (B) Western blotting for UT-7 lysates with sera from 3 patients with PNH⁺ AA (lanes 1-3) and 2 healthy persons (lanes 4-5). Images were obtained using 1000× magnification.