Immunolocalization of collagen types, laminin and fibronectin in the normal human pancreas.

In order to define the connective matrix organization of the normal human pancreas collagen types I, III, pro-III and IV, laminin and fibronectin were labeled using specific, antihuman antibodies. Visualization was by indirect immunofluorescence. Collagen types I, III and pro-III were present within lobules: around acini, ducts and small vessels. Their immunofluorescence reaction was particularly obvious in septa and it also outlined interlobular vessels and ducts. The type III and pro-III fractions possessed a characteristic, branched appearance in many situations, when compared to the more linear type I reaction. Collagen type IV, laminin and fibronectin were closely applied to acini, ducts and vessels, but in contrast to the other collagen types were absent from septa.