Grafting Islets to a Dissected Peritoneal Pouch to Improve Transplant Survival and Function
TRANSPLANTATION
Authors: Kumano, Kenjiro; Vasu, Srividya; Liu, Yang; Lo, Su-Tang; Mulgaonkar, Aditi; Pennington, Jenelle; Darden, Carly M.; Sun, Xiankai; Lawrence, Michael C.; Naziruddin, Bashoo
Abstract
Background. Although the liver is the primary site for clinical islet transplantation, it poses several restrictions, especially limited tissue volume due to portal vein pressure. We evaluated the preperitoneal space as an extrahepatic islet transplant site to deliver high tissue volumes and sustain long-term graft function. Methods. A peritoneal pouch was formed by dissecting the parietal peritoneum from the transversalis fascia of mice. Syngeneic C57BL/6 donor islets were transplanted into the peritoneal pouch of diabetic mouse recipients. Blood glucose was monitored for islet function, and miR-375 was analyzed for islet damage. Islet graft morphology and vascularization were evaluated by immunohistochemistry. [F-18] fluoro-d-glucose positron emission tomography/computed tomography was used to image islet grafts. Results. Transplantation of 300 syngeneic islets into the peritoneal pouch of recipients reversed hyperglycemia for >60 days. Serum miR-375 was significantly lower in the peritoneal pouch group than in the peritoneal cavity group. Peritoneal pouch islet grafts showed high neovascularization and sustained insulin and glucagon expression up to 80 days posttransplantation. A peritoneal pouch graft with high tissue volume (1000 islets) could be visualized by positron emission tomography/computed tomography imaging. Human islets transplanted into the peritoneal pouch of diabetic nude mice also reversed hyperglycemia successfully. Conclusions. Islets transplanted into a dissected peritoneal pouch show high efficiency to reverse diabetes and sustain islet graft function. The preperitoneal site has the advantages of capacity for high tissue volume, enriched revascularization and minimal inflammatory damage. It can also serve as an extrahepatic site for transplanting large volume of islets necessitated in islet autotransplantation.
Switching between GLP-1 receptor agonists in clinical practice: Expert consensus and practical guidance
INTERNATIONAL JOURNAL OF CLINICAL PRACTICE
Authors: Jain, Akshay B.; Ali, Amar; Gorgojo Martinez, Juan J.; Hramiak, Irene; Kavia, Ketan; Madsbad, Sten; Potier, Louis; Prohaska, Ben D.; Strong, Jodi L.; Vilsboll, Tina
Abstract
Background Glucagon-like peptide-1 receptor agonists (GLP-1RAs) are an established treatment for patients with type 2 diabetes (T2D). Differences between GLP-1RAs in pharmacokinetics, dosing regimens and clinical effects, including cardiovascular (CV) outcomes, mean there may be benefits to switching from one to another. However, clinical guidance on switching is lacking and data from clinical trials are limited. This article provides a clinical perspective and consensus on the benefits of switching between GLP-1RAs, the triggers for switching and how best to manage this in clinical practice. Once weekly (OW) semaglutide is used as an example to illustrate how the authors might switch to a different GLP-1RA in clinical practice. Methods Literature was searched and perspectives from 10 healthcare professionals with experience in switching patients with T2D to OW semaglutide from another GLP-1RA were collated. Results Medical triggers for switching to another GLP-1RA included HbA(1c) targets not being met, a desire for additional weight loss, poor adherence, patients moving to increased CV risk status and adverse effects with the current GLP-1RA. Non-medical triggers for switching included patient preference, cost, formulary changes and insurance mandates. Once the decision to switch is made, an individualised approach is recommended, based on considerations that include reimbursement requirements, treatment duration with (and dose of) previous GLP-1RA, the patient's experience initiating the prior GLP-1RA, any concomitant treatment and clinical characteristics. When switching, it is important to emphasise that treatment burden will not increase and that if gastrointestinal adverse effects occur, they are typically transient. Any transient gastrointestinal adverse effects that may occur (or recur) when switching to another GLP-1RA can be reduced by slow up-titration and advising patients to reduce food portion sizes and fat intake. Conclusion Switching from one GLP-1RA to another, such as OW semaglutide, can provide clinical benefits and may delay the need for treatment intensification.