title: Immunocytochemical localization of cleaved caspase-3 in pancreatic islets from type 1 diabetic subjects.
abstract: AIMS/ HYPOTHESIS: Caspase-3 is a main effector caspase of the apoptotic cascade. Involvement of caspase-3 has been implicated in a β cell cloned cell line from type 1 diabetic subjects and in isolated islets from type 2 diabetic subjects.
  
  
  RESULTS
  The control islets revealed cleaved caspase-3 positive cells in about 4.7 % in the total islet cells with large and small islets positive at 4.1 % and 6.8%, respectively. The islets from type 1 diabetic patients showed higher immunopositive cells at 16 % in the total islets with large and small islets positive at 14% and 17%, respectively, 3.4, 3.6 and 2.4 times that of the corresponding control values.
  
  
  METHODS
  Using commercially available rabbit anti-cleaved caspase-3 antibody, immunocytochemical staining was performed on 8 cases of pancreatic tissues from type 1 diabetic subjects and age-matched controls obtained at autopsy. Islets were divided into large islets containing more than 34 islet cells and small islets containing less than 34 islet cells. Cleaved caspase-3 immunostained islet cells were calculated for large and small islets, respectively, with total number of islet cells and total percentage of cleaved caspase-3 positive cells.
  
  
  CONCLUSIONS
  The islets from type 1 diabetics were a mixture of major small-sized islets consisting of insulin-poor and glucagon-rich cells with more caspase-3 positive cells, and occasional large islets, consisting of non-insulin-cells (> 1%) but glucagon- , somatostatin- and PP-rich cells with normal caspase-3 positive cells. The more positive staining for caspase-3 in islets from type 1 diabetics may correspond to accelerated apoptosis cascade in the islets before processing to eventual cell death.
authors.affiliation: Department of Integrative Biosciences, Oregon National Primate Center, Oregon Health and Science University, Portland, USA. tomitat@ohsu.edu
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Tomita
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000818:Animals; D016022:Case-Control Studies; D053148:Caspase 3 / Q000378:metabolism*; D016923:Cell Death / Q000502:physiology; D002469:Cell Separation; D003922:Diabetes Mellitus, Type 1 / Q000378:metabolism / Q000473:pathology*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007515:Islets of Langerhans / Q000378:metabolism* / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D011499:Protein Processing, Post-Translational / Q000502:physiology; D011817:Rabbits; D014018:Tissue Distribution
chemical_list: D053148:Caspase 3