1197 Validation of the MoTiF scanning method for multiplexed cell phenotyping and spatial profiling in melanoma samples

Multiplex immunofluorescence (mIF) visualizes multiple immune markers on a single tissue specimen while preserving spatial context. Compared to immunohistochemistry (IHC) which is limited single-marker staining, mIF allows for cell phenotyping within the tumor microenvironment and can provide clinically relevant prognostic information about response immunotherapy. Recently, our lab has validated use of six-plex assay via AstroPath platform, pathology workflow that creates quantitative spatially resolved datasets by substituting cells in TME stars galaxies. This incorporates multispectral imaging (MSI) scanning technology, requires selection subsequent rescanning HPFs after whole image acquisition. Here we present validation same FFPE melanoma tissues using MoTiF method. Unlike MSI, immediate visualization without need rescan slides, saving significant time workflow. Using HALO quantify marker expression, found no difference densities CD8, CD163, FoxP3, PD-1, PDL-1, Sox10/S100 between staining with IHC method (p>.1). We also observed differences above done performed MSI (p>0.1). Finally, IHC-MoTiF IHC-MSI discrepancies Together, these data demonstrate validity panel, field acquisition advances possibility turn around time.