land-ExM visualizes the protein and lipid context of cells. (A) Workflow of land-ExM. (B) Schematic of NHS-biotin-MA linker. (C) Schematic of mCLING. (D) land-ExM image of U2OS cells incubated with NHS-biotin-MA linker. Scale bar: 10 µm in pre-expansion unit. Linear expansion factor: 4. (E) ExM image of U2OS cells incubated with NHS-MA linker and stained with Alexa Fluor 488 NHS ester dye. Scale bar: 10 µm in pre-expansion unit. Linear expansion factor: 4.2. (F) ExM image of U2OS cells incubated with GMA linker and stained with SYPRO Orange. Scale bar: 10 µm in pre-expansion unit. Linear expansion factor: 4.2. (G) Bar chart comparing signal-to-noise ratios of protein context images obtained with different ExM methods shown in D–F. The signal-to-noise ratio is calculated as the average pixel value of the area with cells divided by the average pixel value of the area without cells in each image. Each bar represents the mean ± standard error of more than 10 cells. (H–J) Different views of land-ExM images of a breast cancer cell, UCI082014, stained with mCLING for lipid content. The orange dashed lines in H show where the orthogonal views (I and J) align. Scale bar: 5 µm (H), 2 µm (I and J) in pre-expansion unit. Linear expansion factor: 3.8. (K) Magnified images of H. (L) Magnified images of I. The orange dashed line in K shows where the orthogonal view (L) aligns. Scale bar: 0.5 µm in pre-expansion unit. Linear expansion factor: 3.8. All images were taken with an Airyscan microscope. Images D–F were adjusted to the same contrast. Image in D is also shown in Fig. S3 C.