The Tissue Analysis Core (TAC) within the AIDS and Cancer Virus Program will process, embed, and perform microtomy on fixed tissue samples presented in ethanol. Collagen I, Collagen III, or Fibronectin immunohistochemistry will be performed, in order to ascertain the extent of extracellular matrix (ECM) deposition (i.e., fibrosis) that has accumulated within secondary lymphoid tissues. To ensure consistency among assay batches, we will utilize an automated immunohistochemistry (IHC) system. High-resolution digital images of each IHC stained sample will be generated using the Aperio ScanScope CS System. Regions of interest (ROI; 20–30) of a defined size will be highlighted on each digital image using the Aperio ImageScope software regions tool, and high-resolution images of ROIs will be generated using a custom-written software program created by the Imaging and Visualization Group that automatically extracts ROIs from the digital slide annotation layer. Finally, under the guidance of a subject matter expert, the TAC will provide comprehensive quantitative image analysis using a custom series of unique actions in Photoshop with Fovea tools to determine the percent area in each high-resolution image that is occupied by fibrotic collagen. Relevant data will be provided electronically, and a report with interpretation/conclusions will be supplied. Sufficient basic consultation with a subject matter expert is included with the service.