Fig. 5: PNPs, particularly immune-mediated subtypes, exhibit focal perineurial hyperplasia.

A Spatial-seq was performed on sural nerve samples from a total of eight patients (two per disease). Representative spatial transcriptomics images of perineurial marker genes of CTRL (S24), VN (S30), CIDP (S01), and CIAP (S14). Each dot indicates the expression of one transcript. B Average gene expression of CXCL14 expression per disease group in snRNA-seq. C Representative immunofluorescence images showing CXCL14 staining in CTRL (S24) vs. CIDP (S08) (left panel). Immunofluorescence staining was performed on a minimum of six sural nerve sections per patient from a total of four patients. The quantification of the CXCL14-positive area in the perineurium is visualized in a boxplot (right panel). Box plots show the median, interquartile range (IQR), and whiskers extending to 1.5 × IQR. Dots represent individual measurements (technical replicates; S24/S08/S09: n = 8, S25: n = 6). D EMA staining was performed on sural nerve samples from a total of 30 patients. Representative images of epithelial membrane antigen (EMA) staining in CTRL (S71) and CIDP (S76). E, F The inner and outer perimeters, along with the corresponding area, were measured in CTRL (n = 18) and CIDP (n = 12) patients. A linear mixed model was used to adjust for confounding variables (Methods) and to determine statistical significance (two-sided t test). Box plots show the median, interquartile range (IQR), and whiskers extending to 1.5 × IQR.