Expression of ULBP2, ULBP3, and IL-4 and localization of Vδ1 T cells in NHL in situ. Thin sections (5 μm) from frozen LNs of 6 FL NHL patients were immunostained with anti-ULBP2 (B), anti-ULBP3 (C), anti–IL-4 (D), or anti-Vδ1 (E) or anti-Vδ2 (F) mAbs, all at 5 μg/mL, followed by the peroxidase revelation system and counterstained with hematoxylin. Panel A is a negative control, an isotypic unrelated antibody (CTR). Arrows in panels B-E indicate positive cells. Slides were cover-slipped and analyzed under a IX70 microscope, equipped with a CCD camera, at ×20 magnification (A-D, bar represents 40 μm), or at ×40 magnification (E-F, bar represents 20 μm). Images were captured with Olympus Plan APO 20×/0.40 NA (A-D) or Olympus UAPO 40×/1.35 NA oil objectives. The total magnification was 200× or 400× according to the 20× or 40× objective used. Images were taken with CELL Olympic Biosystem imaging software version 2.0.