Advantages of replacing hydroxyethyl starch in University of Wisconsin solution with hyperbranched polyglycerol for cold kidney perfusion

Evaluation of hyperbranched polyglycerol for cold perfusion and storage of donor kidneys in a pig model of kidney autotransplantation

“…Replacing the HES with the HPG (1 kDa, 3% wt/vol) in the UWS results in a 2.5‐fold decrease in its relative viscosity, 21 resulting in increasing perfusion rate and more blood washout in the pig kidneys in this study (Figure 1). Similar observation is seen in the mouse kidneys 22 . The functional recovery of the kidneys after cold perfusion and static storage with the HPGS is significantly improved as compared with those with the UWS in the pig model (Figure 4).…”

“…Inclusion of HES in the UWS or others results in high viscosity and induction of RBC hyperaggregation, 15 which is a disadvantage factor for its use in organ perfusion. Unlike HES, HPG did not induce RBC hyperaggregation, and it was more effective in the blood washout and prevented more tissue damage than HES in the cold perfusion of mouse kidneys 22 . Furthermore, in a rat model of cold ischemia–reperfusion injury, less reperfusion injury was seen in the kidneys after cold perfusion/storage with the HPGS than those with HES‐based UWS or HTK solution 23 .…”

“…The HPGS was prepared by dissolving 1 kDa HPG polymer (3%, wt/vol) in a chemical composition similar to Belzer UWS (Bridge to Life Ltd, Columbia, SC) (Table S1) as described previously 21,22 . The pH of the HPGS was measured and adjusted to 7.2–7.4 with NaOH/HCl solutions by using a Fischer Scientific Accumet pH meter (Fisher scientific, Ottawa, ON, Canada), and its osmolality (mOsm/kg) was determined by using the Advanced® Model 3,320 Micro‐Osmometer (Advanced Instruments, Inc., Norwood, MA) in the Vancouver Coastal Health Regional Laboratory Medicine (Vancouver, BC, Canada).…”

“…Indeed, replacing HES with HPG (1 kDa, 3%) in the UWS significantly reduces its relative viscosity from 3.514 to 1.378 at 4°C, more than a 2.5‐fold decrease 21 . In rodent models, cold perfusion and storage with a HPG‐based preservation solution (HPGS) more effectively prevents the mouse organ (both hearts and kidneys) from damage than with the UWS, 21,22 and more effectively reduces kidney injury than both the UWS and HTK solution in a rat model of cold kidney ischemia–reperfusion 23 . Unlike the rodent kidneys, the multilobular structure and intrarenal arteries and vein of the pig kidneys are similar to the human kidneys.…”

Preservation Solutions for Kidney Transplantation: History, Advances and Mechanisms

“…Despite its popularity, recent studies have suggested potential disadvantages of UW solution, including a) high viscosity generated by HES, which complicates tissue wash-out and saturation with preservation solution 32 ; b) addition of penicillin G, dexamethasone, and insulin before use 20 ; and c) the current cost per liter of UW solution is $282, and the total cost of UW solution per liter is over $300 when additives are included 20 . Therefore, further modifications have been made to create more effective or economical solutions, such as RPS-96 (UW lacking HES) 33 , dextran 40-based UW (replacing HES with dextran 40 in UW) 34 , perfluorocarbons (PFC)-based UW 35 , hyperbranched polyglycerol (HPG) solution (replacing HES with HPG in UW) 36 , and sodium lactobionate sucrose (SLS) solution (replacing raffinose with sucrose in UW) 37 .…”