Genentech 3 articles published in JoVE Biology Standardized Processing for Formalin-Fixed, Paraffin-Embedded Cell Pellet Immunohistochemistry Controls Charles Havnar1, Kathy Hotzel1, Carmina Espiritu1, Amy Lo1, Joshua D. Webster1 1Department of Pathology, Genentech Presented here is a protocol for generating formalin-fixed, paraffin-embedded cell pellet controls for immunohistochemistry. Cancer Research Spatial Profiling of Protein and RNA Expression in Tissue: An Approach to Fine-Tune Virtual Microdissection Veronica Ibarra-Lopez1, Sangeeta Jayakar1, Yeqing Angela Yang2, Ciara Martin3, Zora Modrusan2, Sandra Rost1 1Department of Pathology, Genentech, 2Department of Microchemistry, Proteomics, Lipidomics & Next Generation Sequencing (MPL-NGS), Genentech, 3NanoString Technologies Here, we describe a protocol for fine-tuning regions of interest (ROIs) for Spatial Omics technologies to better characterize the tumor microenvironment and identify specific cell populations. For proteomics assays, automated customized protocols can guide ROI selection, while transcriptomics assays can be fine-tuned utilizing ROIs as small as 50 µm. Biochemistry The Peel-Blot Technique: A Cryo-EM Sample Preparation Method to Separate Single Layers From Multi-Layered or Concentrated Biological Samples Matthew C. Johnson*1,2, Arshay J. Grant*1, Ingeborg Schmidt-Krey1,3 1School of Biological Sciences, Georgia Institute of Technology, 2Department of Structural Biology, Genentech, 3School of Chemistry and Biochemistry, Georgia Institute of Technology The peel-blot technique is a cryo-EM grid preparation method that allows for the separation of multilayered and concentrated biological samples into single layers to reduce thickness, increase sample concentration, and facilitate image processing.