Heat maps were generated using SCMS data obtained from all four cell groups (Figure ), depicting the changes in abundances of the top 100 metabolites in both positive (Figure ) and negative (Figure ) ionization modes. The rows represent different metabolites, and the columns represent individual cells, with colors indicating the relative abundance of each metabolite. Clear trends can be observed for metabolites across 120 single cells in four groups (with 30 single cells in each group).