“Pathology Working Group to Review the Urinary Bladder from Cynomolgus Monkeys”
"Immunohistochemistry"
The Pathology Working Group (PWG) to review the urinary bladder from Cynomolgus monkeys was conducted June 26-27, 2007, in Research Triangle Park, NC, by Experimental Pathology Laboratories, Inc., (EPL) on behalf of the ILSI Health and Environmental Sciences Institute’s (HESI) PPAR Agonist Project Committee. The focus of the PWG was to establish consistent diagnostic criteria to characterize any changes that may be relevant in the urothelium of the urinary bladder in monkeys exposed to PPAR agonists. The PWG specifically addressed morphologic changes that may indicate toxic injury or preneoplastic proliferative responses.
During the PWG exercise, the panel identified treatment-related vacuolation within the urothelial cells in the urinary bladder of monkeys that received PPAR agonists. Within these vacuoles, there were small accumulations of granular material and small amounts of cellular debris. At HESI’s request, EPL conducted an immunohistochemistry (IHC) investigation of the cellular debris present within vacuoles to determine if they originate from macrophages (marker: CD68), T and/or B lymphocytes (CD45, pan-lymphocyte marker), or degenerating urothelial cells (Pan-CK, pan-keratin stain). Links to the draft IHC pathology report and the IHC images are given below. The results of the IHC investigation will be included in the published PWG manuscript on monkey urinary bladder.
NOTE: Only funding companies of the Pathology Working Groups and scientific advisors to the HESI PPAR Agonist Project Committee are eligible to receive the final PWG report. Dr. Jerry Hardisty (EPL) is preparing a manuscript for publication which summarizes the final report. Until the manuscript is completed, submitted, and accepted by a peer-reviewed journal, please do not distribute the final report.
Downloads: PDF format