Fig. 5: Markers of liver fluke somatic tissues: gut, tegument and parenchyma.

a, c Fluorescent in situ hybridization (FISH) overview (left) and spatial projection (right) of the gut marker legumain (D915_002224) (a) and a tegumental EF hand domain-containing protein (D915_003074) (c). Section orientation is indicated at the bottom (dors: dorsal, vent: ventral, lat: lateral). b, d Magnification of (a) and (c), respectively. e FISH (left) and spatial projection (right) of cathepsin B (D915_007096). This cathepsin B is expressed in the worm parenchyma as well as in the gut, white arrowheads indicating positive parenchymal cells. a, c, e Expression level encoded by color (gray = low, red = high). f FISH of basement membrane-specific heparan sulfate proteoglycan core protein (HSPG) (D915_0000229). HSPG is expressed in small cells within the worm’s parenchyma (white arrowheads) as well as in larger cells below the tegument (white arrows). g FISH of cathepsin L (D915_011077). h FISH of cytoplasmic type actin 1 (D915_007443). i DotPlot showing expression profiles of selected tissue markers of the gut, tegument or parenchyma cluster. Dot color encodes the average expression level (mean of UMI counts, normalized and scaled) across all spots within a cluster. Dot size encodes the percentage of spots within a cluster that have captured this transcript. Please note: While spatial plots (a, c, e, k) are shown for only one representative section, the DotPlot includes expression data from all four tissue sections in the dataset. Genes labeled in red were validated by FISH. Figure panels showing the respective FISH experiment and/or spatial projection are indicated. Source data are provided as a Source Data file. j FISH of a tegument-specific tetraspanin (D915_000797). k Spatial projections showing expression patterns of selected vaccine candidate genes: saposin-like family protein 2 (SAP2, D915_010001), cathepsin L1 (CL1, D915_005527), leucine aminopeptidase (LAP, D915_002812), tegumental calcium-binding protein CaBP1 (D915_003183), uncharacterized tegumental protein Fhteg1 (D915_000758), fatty acid-binding protein Fh15 (FABP, D915_003367), helminth-defense molecule 1 (HDM1/MF6, D915_007621). Expression level encoded by color (gray = low, red = high). a–h, j Scale = 100 µm. g: gut, ov: ovary, par: parenchyma, teg: tegument, tes: testis, ut: uterus, vit: vitellarium. For numbers of ISH experiments performed for each gene, see “Statistics and reproducibility” and Supplementary Data 9.