Fig. 3

Regional variation in the oligodendroglial population. Differential abundance analysis using Milo shows regional differences between a CSC and BA4, b CB and BA4 and c CB and CSC. Significant increases are coloured in red/blue according to region (FDR < 0.1). Each dot represents a neighbourhood consisting of an average of 50–100 cells. OPC_A is more abundant in CB and CSC, and OPC_B in BA4. Oligo_C and Oligo_F are enriched in the spinal cord compared to the other regions. Oligo_F is a smaller cluster but strikingly different from the other oligodendrocytes in its transcriptome including genes associated with astrocytes (such as SPARC) and Schwann cells (MPZ) while clearly not being an astrocyte or Schwann cell based on the absence of relevant lineage markers. d, e Quantification by immunofluorescence (shown in Fig. 2c) showing the increased abundance of Oligo_F in the human spinal cord using the markers d SPARC + OLIG2 + RBFOX1- and e HCN2 + SPARC + OLIG2 + . f, g Quantification by BaseScope duplex of regional selectivity of OPC_A and B (example in Fig. 2d) showing that f PAX3-positive OPC_A are more abundant in CB and CSC and g NELL1-positive OPC_B are BA4 specific. Plots visualize percentage of total OLIG2 d, e or PDGFRA f, g -positive cells. Boxes in plots visualize median and 25th and 75th percentiles and whiskers mark range up to 1.5 * inter-quartile ranges to show potential outliers. See Table 1 for number of samples, statistical tests used and results and Addtional file 1: Table S2 for sample information. h Volcano plot showing differential gene expression between BA4 OPC_B and CSC OPC_A. i Gene ontology analysis based on differentially expressed genes of CSC OPC_A in comparison to BA4 OPC_B as shown in h) (complete version in Additional file 1: Fig. S7). Differentially expressed genes in oligodendrocytes (oligos) with tissue region j–l with red arrows indicating genes that are discussed in the main text. m Gene ontology terms of genes enriched in spinal cord oligodendrocytes in comparison to brain oligodendrocytes. (Complete version in Additional file 1: Fig. S8)