Orthotopic Rat Kidney Transplantation: A Novel and Simplified Surgical Approach

Summary

The purpose of this manuscript and protocol is to explain and demonstrate in detail the surgical procedure of orthotopic kidney transplantation in rats. This method is simplified to achieve the correct perfusion of the donor kidney and shorten the reperfusion time by using the venous and ureteral cuff anastomosis technique.

Abstract

Kidney transplantation offers increased survival rates and improved quality of life for patients with end-stage renal disease, as compared to any type of renal replacement therapy. Over the past few decades, the rat kidney transplantation model has been used to study the immunological phenomena of rejection and tolerance. This model has become an indispensable tool to test new immunomodulatory pharmaceuticals and regimens prior to proceeding with expensive preclinical large animal studies.

This protocol provides a detailed overview of how to reliably perform orthotopic kidney transplantation in rats. This protocol includes three distinctive steps that increase the probability of success: perfusion of the donor kidney by flushing through the portal vein and the use of a cuff system to anastomose the renal veins and ureters, thereby decreasing cold and warm ischemia times. Using this technique, we have achieved survival rates beyond 6 months with normal serum creatinine in animals with syngeneic or tolerant kidney transplants. Depending on the aim of the study, this model can be modified by pre- or posttransplant treatments to study the acute, chronic, cellular, or antibody-mediated rejection. It is a reproducible, reliable, and cost-effective animal model to study different aspects of kidney transplantation.

Introduction

Historically, the first transplant rejection studies were performed by Brent and Medawar using skin transplants in rodents¹. It soon became clear that skin has distinct immunological features, making it a highly immunogenic organ that is different in rejection from other vascularized solid organs². Rat studies of solid organ transplant rejection are habitually limited to heart, liver, and kidney transplants. Although each of these organs is suitable to study rejection, there are advantages and disadvantages to each of them. Heart transplants are often transplanted into the abdomen and anastomosed to the aorta and vena ca....

Protocol

Lewis (RT1¹) and Dark Agouti (DA) (RT1A^a) rats were purchased from commercial vendors (see the Table of Materials). These fully MHC-mismatched strains are often used to study acute renal allograft rejection. All animals were housed and maintained according to the National Institutes of Health’s (NIH) guidelines in a specific pathogen-free facility at the Johns Hopkins University. All procedures were approved by the institutional animal care and use committee.

Discussion

In this manuscript, we describe the surgical method for orthotopic KT in rats in detail, including all the necessary equipment needed to perform this procedure (Figure 5). In 1965, Fisher and Lee published the first report on KT in rats, which became the start of an exciting investigative field¹⁸. Since then, many modifications have been introduced to improve the reproducibility of this model. It has served as an effective animal model for studying ischemia-reperfusio.......

Materials

Name	Company	Catalog Number	Comments
Buprenorphine HCL	Reckitt Benckiser Healthcare UK	NDC12496-0757-5
Dissecting forceps, curved	Zhenbang, China		11cm Flat handle
Heparin sodium injection USP	Sagent Pharmaceuticals	NDC25021-400-10
Micro-forceps, straight, smooth	Jingzhong, China	WA3010
Micro needle holder	Jingzhong, China	WA2010
Micro vessel clamps	Jingzhong, China	WA40120
Micro spring sciccor 1	ROBOZ	RS-5620
Micro spring sciccor 2	F.S.T.	91501-09
Micro spring sciccor 3	Zhenbang, China		8.5cm Vannas,curved
Prograf (Tacrolimus/FK506)	Astellas
Rats	Charles River & Taconic Biosciences	LEW/Crl & DA-M
Shaver	Wahl	79600-2101
Suture 4-0	Ethicon	J304H
Suture, 4-0	Ethicon	683G
Suture, 10-0	Ethicon	2820G
Syringes & Needles	BD
Thread, 8-0	Ashaway	75290
Ureteral cuff	Microlumen	160-1	Polymide Tubing, Diameter 0.41 mm
Venous cuff	Intramedic BD	7441	PE-200 Non-radiopaque polyethylene tubing ID: 1.4 mm, OD: 1.9 mm