title: A high-molecular IGF-2 immunoreactive peptide (pro-IGF-2?) in the insulin cells of the islets of Langerhans in pancreas of man and rat.
abstract: Histopathologically normal pancreatic parenchyma from 12 adult men and women, as well as that from 14 adult rats (Sprague-Dawley and Wistar strains), were investigated immunohistochemically with a mouse monoclonal antibody, raised against recombinant human pro-IGF-2. The antiserum showed no crossreactivity with insulin; IGF-1 had 0.1% of the reactivity of IGF-2. The immunohistochemical observations were checked by means of a radioimmunoassay (RIA), based on the same antibody, of an extract of a sample of one of the human pancreatic glands. Analogous investigations for insulin were made in parallel, using polyclonal insulin antisera. A high-molecular (12 kDa) IGF-2-like peptide was found in the islets of Langerhans, being localized to the insulin cells. These cells were identified as beta-cells by immunohistochemistry with insulin antisera on adjacent paraffin sections. From observations made by means of acid-gel-chromatography, the peptide was tentatively supposed to represent either pro-IGF-2, or a partially processed form of it.
authors.affiliation: Department of Tumour Pathology, Karolinska Institute and Hospital, Stockholm, Sweden.
authors.forename: A
authors.initials: A
authors.lastname: Höög
authors.forename: L
authors.initials: L
authors.lastname: Grimelius
authors.forename: S
authors.initials: S
authors.lastname: Falkmer
authors.forename: V R
authors.initials: VR
authors.lastname: Sara
mesh_terms: D000818:Animals; D002850:Chromatography, Gel; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007328:Insulin / Q000032:analysis*; D007335:Insulin-Like Growth Factor II / Q000032:analysis* / Q000737:chemistry; D007515:Islets of Langerhans / Q000737:chemistry*; D008297:Male; D008970:Molecular Weight; D011498:Protein Precursors / Q000032:analysis* / Q000737:chemistry; D011863:Radioimmunoassay; D051381:Rats; D017207:Rats, Sprague-Dawley; D017208:Rats, Wistar; D011994:Recombinant Proteins
chemical_list: D007328:Insulin; D011498:Protein Precursors; D011994:Recombinant Proteins; C066038:proinsulin-like growth factor II; D007335:Insulin-Like Growth Factor II