Fig. 1: Identification, isolation and analysis of isolated islets and exocrine tissue.

a Schematic illustrating the experimental workflow: pancreatic islets were isolated from formalin-fixed paraffin embedded (FFPE) pancreatic tissue sections. Their proteome was characterised by liquid chromatography-mass spectrometry (LC-MS/MS) and between group comparisons analysed. Data analysis included between-group comparisons using permutation-based testing to correct for multiple comparisons using a false discovery rate (FDR) of < 0.05. No statistical data are presented in this figure. Created in BioRender. Stefana, I. (https://BioRender.com/3j35qyz). b Identification of islets by brightfield and fluorescence (488 nm channel) microscopy. Images of islets at 20x magnification before laser-capture microdissection (LCM) are shown. Scale bar = 200 µm. c Brightfield and fluorescence images of islets post-LCM. Scale bar = 200 µm. Images in (b, c) are representative of 12 biological replicate samples included in the analysis, with 9–12 islets dissected per sample, and similar results observed across all islets within each biological replicate. d Number of proteins detected per sample type following LC-MS/MS. e Principal component analysis plot of the samples. Isolated islets are represented as circles (pregnant cases in pink, controls in green), while exocrine tissue samples are shown as squares (pregnant cases in blue, controls in orange). f Identification of islet proteins, volcano plot comparing protein expression between isolated islets (pregnant and non-pregnant controls) and exocrine tissue (pregnant and non-pregnant controls). Significantly upregulated proteins are shown in purple, and downregulated proteins in red. Selected proteins with a log2 fold change > 3 or < −3 are labelled. FDR < 0.05 = - log10 FDR > 1.3, S0 = 0.01. g Overrepresentation analysis of enriched pathways from the Reactome, KEGG, and GO Biological Processes databases. Pathways with FDR < 0.05 are shown.