Distinct activation patterns of Mφ in tumor samples. Adjacent sections of paraffin-embedded hepatocellular (A) or nasopharyngeal (B) carcinoma were stained with an anti-CD68, anti-HLA-DR, or anti-IL-10 Ab (magnification ×160 in panel A and ×100 in panel B). The micrographs at higher magnification show the stained cancer nest,1 peritumoral stroma,2 and adjacent normal tissue.3 IL-10–positive Mπ are seen in the cancer nest, and Mφ with high HLA-DR expression have accumulated in the immediate vicinities of the cancer nest in hepatocellular carcinoma in panel A. Slides were viewed with a Leica DM IRB inverted research microscope (Leica Microsystems, Wetzlar, Germany) using a HI PLAN CY lens at 10 ×/0.25 PH and 40 ×/0.65 PH2 0.17/, 0.36 and Klear Mount medium (GBI Inc, Mukilteo, WA). Images were acquired using a QImaging camera (Surrey, BC, Canada), model Retiga 4000RV Fast 1394 Mono Cooled, and were processed with Image-Pro Plus 5.0 (Media Cybernetics, Silver Spring, MD) and Adobe Photoshop 7.0 (Adobe Systems, San Jose, CA) software.