Mab1926

Human fetal pancreas samples were fixed in 4% paraformaldehyde and paraffin embedded. Sections (4 μm) were prepared and stained with either appropriate dilutions of primary antibodies, including CK19 (M0888, Dako), pancreatic and duodenal homeobox 1 (PDX-1; Dr. Wright, University of Vanderbilt), insulin (18-0067, Invitrogen, Camarillo, CA, USA), glucagon (G2654, Sigma), somatostatin (ab30788, Abcam), pancreatic polypeptide (18-0043, Zymed), amylase (171534, Calbiochem), collagen I (ab6308, Abcam), collagen IV (MAB1910), laminin (AB19012) and fibronectin (MAB1926, Millipore) or Schiff's reagent for PAS staining (24200-1, Polysciences Inc.).¹⁶ (link) Slides were then treated with either fluorescent secondary antibodies (obtained from Jackson Immunoresearch Laboratories) or haematoxylin as a counterstain, and at least 3 pancreata per age group were examined.

Cells were permeabilised with Triton X-100 (1%, 20 min) and probed with an antibody to FOXQ1 (sc-47597), FOXN2 (sc-67490), fibronectin (MAB 1926, Millipore) or laminin V (MAB 1949, Millipore) followed by visualization with a secondary antibody conjugated to Alexa-Fluor 488 (A11001; Life Technologies) or Alexa-Flour 568 (A11055; Life Technologies) and co-staining with DAPI on a Nikon C1 plus confocal system. Expression was quantified using Fiji-ImageJ. The Mann–Whitney non-parametric test was used to determine significance (Prism).