Visualizing ultrastructural details of placental tissue with super-resolution structured illumination microscopy

Super-resolution fluorescence microscopy is a widely employed technique in cell biology research, yet remains relatively unexplored in the field of histopathology. Here, we describe the sample preparation steps and acquisition parameters necessary to obtain fluorescent multicolor super-resolution structured illumination microscopy (SIM) images of both formalin-fixed paraffin-embedded and cryo-preserved placental tissue sections. We compare super-resolved images of chorionic villi against diffraction-limited deconvolution microscopy and show the significant contrast and resolution enhancement attainable with SIM, demonstrating the applicability of this imaging technique for both clinical diagnosis and biological research.