Transplant Islets Into the Pinna of the Ear: A Mouse Islet Transplant Model

Transplant Proc. 2021 Jan-Feb;53(1):450-456. doi: 10.1016/j.transproceed.2020.06.040. Epub 2020 Sep 11.

Abstract

Background: Islets transplanted under the ear skin would allow easy observation of the graft response and survival in vivo. This research was designed to establish an efficient mouse islet transplant model to probe the dynamic cellular interplay in vivo.

Methods: Green fluorescent protein transgenic mice and BALB/c mice were used as donors and recipients. All recipients were divided into 6 groups of 6 mice each. First, we treated the transplant recipients, including diabetes induction, autologous epididymal fat pad, and MATRIGEL transplant to the ears. Then, 1. we transplanted isolated islets to the ear/ear with fat/ear with MATRIGEL; and 2. transplanted islets with collagen + basic fibroblast growth factor or islets with collagen + vascular endothelial growth factor. Mice in the control group received a sham transplantation with phosphate buffer saline. All recipients were then observed for 30 days with blood glucose (BG) monitoring. Finally, ears were removed with graft on day 28 for histologic examination.

Results: It was suggested that transplant of islets alone could not correct hyperglycemia. Fat, MATRIGEL, collagen, and growth factors have the similar function to form a microenvironment conducive to islet survival. The effect of islet transplantation for correcting hyperglycemia of the fat modification group was better than other groups (P < .05). BG could be normalized, and living islets were detected by anti-insulin immunohistochemistry.

Conclusions: Transplant islets into the ear with transplanted autologous fat is the optimal way which can be used to analyze the allograft response in vivo and track cell population and migration using labels by confocal microscopy.

MeSH terms

  • Adipose Tissue / transplantation*
  • Animals
  • Blood Glucose / metabolism
  • Collagen / metabolism
  • Collagen / pharmacology*
  • Diabetes Mellitus, Experimental / blood
  • Disease Models, Animal*
  • Drug Combinations
  • Ear*
  • Fibroblast Growth Factor 2 / metabolism
  • Graft Survival
  • Islets of Langerhans Transplantation*
  • Laminin / pharmacology*
  • Male
  • Mice
  • Mice, Inbred BALB C
  • Proteoglycans / pharmacology*
  • Transplantation, Homologous / methods
  • Vascular Endothelial Growth Factor A / metabolism

Substances

  • Blood Glucose
  • Drug Combinations
  • Laminin
  • Proteoglycans
  • Vascular Endothelial Growth Factor A
  • Fibroblast Growth Factor 2
  • matrigel
  • Collagen