ABSTRACT
Aim: pancreatic islets encapsulation is an alternative for using the immuno-suppression to prevent rejection. We used the amniotic membrane as a macro-capsulation. The main objective was to assess the re-vascularization of the allogenic amniotic membrane macro capsule in different sites to ensure the islet viability when using it for encapsulation
Methods: 30 amniotic membranes macro capsules were implanted in 15 dogs in two different sites; in the sub-deltoid shoulder region and in a piggy bag pouch in the recipient peritoneal cavity under general anesthesia. The capsules are removed after day 1, 3, 7, 10, 15, 21, 30 and 60 days. All the capsules are subjected to histo-pathological examination and immuno-histochemistry for neo-vascularization using VEGF, Factor VIII and CD4, CD8 for detection of rejection
Results: all specimens showed inflammation and congested blood vessels with no thrombosis or rejection. VEGF expression and Factor VIII were increased; neo-vascularization associated with vascular invasion but no inflammatory cells of acute rejection. CD4 and CD8 showed mild rejection
Conclusion: the implantation of the amniotic sac macro capsule was fixed nicely within the omental tissue and the sub-deltoid region with minimal or no sign of rejection. Our results should help the clinical application of using this capsule as an immuno-isolator for pancreatic islets transplantation
ABSTRACT
Introduction: Extensive hepatic resection could be done by performing pre-operative portal vein embolization [PVE], to induce compensatory hypertrophy in the predicted remnant liver. The aim of this study is to evaluate the effect of selective [PVE] on hepatocytes
Methods: The study was done on 23 adult Shin Sheila rabbits, embolization of the lateral right branch of the portal vein using Histoacryl was done. The animals were divided into 2 groups: [group-A] ; 12 animals sacrificed in < 30 days and [group-B]; 11 animals sacrificed between 30 to 60 days. Biopsies were taken from embolized [E] and non embolized [NE] lobes and examined
Results: Degeneration was remarkable in [E] lobe in [group-A], while it was not noticeable in [group-B]. Regeneration was evident in [E] lobe in [group-B]. Proliferation occurred in [NE] lobes in [group-A] in the [NE] lobes. Regeneration was marked in [group-B] in the [E] lobe. Morphometric DNA study showed apoptosis in the [E] lobe of [group-A] were more than in the [NE] lobes while in [group-B] they were nearly the same in both lobes
Conclusion: PVE induce apoptotic changes in [E] lobe in the early stage this was re-compensated by increased cellular proliferation in late stage evident by increased in S phase fraction of DNA by image analysis study