ANCA patterns and recognition thereof by mathematical algorithms. (a) Images (detail) of serum samples demonstrating C-ANCA, P-ANCA, and atypical ANCA patterns on ethN and formN taken automatically by AKLIDES™. Chromatin is stained by DAPI (blue) and specific ANCA interactions are revealed by FITC (green)-labeled secondary anti-human IgG. (b) Pattern recognition image of perinuclear (A) and cytoplasmic (B) specific staining of neutrophils used by the novel algorithms for pattern differentiation: DAPI (blue) and FITC fluorescence intensity signals (green) of respective images were combined and illustrated in three dimensions (x - object length, y - object width, light intensity of fluorescence signal). C-ANCA, cytoplasmic antineutrophil cytoplasmic antibody; ethN, ethanol-fixed neutrophils; formN, formalin-fixed neutrophils; P-ANCA, perinuclear antineutrophil cytoplasmic antibody.