Extended Data Fig. 4: Single-cell RNA sequencing of SCLC cells after co-culture with neurons, either with or without addition of tetrodotoxin, reflects distinct subpopulations of cells that cluster separately from SCLC cells in monoculture.

a, Representative immunofluorescence of neuronal populations present in primary neuronal co-cultures demonstrating presence of glutamatergic (VGLUT2, white) and GABA-ergic (GAD65, red) neurons and absence of astrocytes (GFAP, green). Scale bar = 100 µm. Data from 2 independent experiments. b, Quantification of data in a, demonstrating approximately equal proportions of glutamatergic and GABA-ergic neurons. c, Expression of membrane GFP (mGFP) in 16T SCLC cells grown in monoculture or isolated from co-culture with primary murine neurons. d, Composition of the 16 clusters depicted in Fig. 2g as percentage of cells isolated from the monoculture (grey) or co-culture (black) conditions. e, Gene Ontology (GO) enrichment analysis for the top pathways expressed by cells in cluster 14. f, UMAP embedding of single cell RNA-seq profiles of murine 16T SCLC cells isolated from monoculture (grey) or co-culture (black) with primary murine neurons in the presence of 1 µM TTX. 44,562 cells were analyzed from 3 biological replicates. g, Expression of membrane GFP (mGFP) in cells from f. h, Composition of the 18 clusters depicted in Fig. 2k as percentage of cells isolated from the monoculture (grey) or co-culture (black) in the presence of TTX conditions.