Significance of the peri-insular extracellular matrix for islet isolation from the pancreas of rat, dog, pig, and man.
The presence and distribution in the peri-insular region of extracellular matrix, and in particular basement membrane, was investigated in a comparative study comprising pancreata of rat, dog, pig, and man. Basement membrane markers, collagen type-IV and laminin, were determined immunohistochemically. Additional information pertaining to the structural relationships between endocrine and exocrine pancreas, in particular cell-to-cell and cell-to-matrix contacts, was obtained by electron microscopy. In pig, very little peri-insular capsule is present, and the structural integration of the porcine islet in the exocrine pancreas almost exclusively depends on cell-to-cell adhesion. In the canine pancreas, the islets are almost completely encapsulated with very little direct exocrine-to-endocrine cell-to-cell contact. In rat and man, the situation is intermediate with a tendency towards predominance of cell-to-matrix adhesion. The intra-insular adhesion mechanisms depend largely on cell-to-cell adhesion in all four species. The ultrastructural results suggest that collagenase preparations employed in islet isolation procedures should be of high purity as to preserve the protease-sensitive intra-islet cell-to-cell adhesion. Under these conditions, however, the endocrine-to-exocrine cell-to-cell contacts will be conserved also, resulting in an exocrine-tissue contamination of the islets of Langerhans. Consequently, additional steps for the effective removal of exocrine tissue and the purification of islets are required.
van Deijnen
J H
JH
Department of Surgery, University of Groningen, The Netherlands.
Hulstaert
C E
CE
Wolters
G H
GH
van Schilfgaarde
R
R
D000328:Adult; D000818:Animals; D001485:Basement Membrane / Q000378:metabolism; D002448:Cell Adhesion; D002469:Cell Separation; D003094:Collagen / Q000378:metabolism; D004285:Dogs; D005109:Extracellular Matrix / Q000378:metabolism; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007515:Islets of Langerhans / Q000166:cytology* / Q000378:metabolism; D016381:Islets of Langerhans Transplantation; D007797:Laminin / Q000378:metabolism; D008297:Male; D008854:Microscopy, Electron; D051381:Rats; D011919:Rats, Inbred Strains; D013045:Species Specificity; D013552:Swine
D007797:Laminin; D003094:Collagen