Patch2MAP combines patch-clamp electrophysiology with super-resolution structural and protein imaging in identified single neurons without genetic modification.

Recent developments in super-resolution microscopy have revolutionized the study of cell biology. However, dense tissues require exogenous protein expression for single cell morphological contrast. In the nervous system, many cell types and/or species of interest - particularly humans - are not amenable to genetic modification and exhibit intricate anatomical specializations which make cellular and subcellular delineation challenging. Here, we present a method we call Patch2MAP for full morphological labeling of individual neurons from any species or cell type for subsequent cell-resolved protein analysis at the nanoscale. By combining patch-clamp electrophysiology with epitope-preserving magnified analysis of proteome (eMAP), our method additionally allows for correlation of physiological properties with subcellular protein expression. We applied Patch2MAP to individual spiny synapses in human cortical pyramidal neurons and demonstrated that electrophysiological AMPA-to-NMDA receptor ratios correspond tightly to respective protein expression levels. We further used Patch2MAP to investigate neuron-to-glioma synapses in surgically resected tissue from a human glioblastoma patient. Patch2MAP thus permits combined subcellular functional, anatomical, and protein analyses of any cell, opening new avenues for direct molecular investigation of the human brain in health and disease.