Early Application of Auxiliary Partial Orthotopic Liver Transplantation in Murine Model of Wilson Disease

Auxilliary Liver Transplantation According to the RAPID Procedure in Noncirrhotic Patients: Technical Aspects and Early Outcomes

OBJECTIVE

To present technical details and short-term experiences of liver transplantation as a 2-stage procedure using small for size grafts in a multicenter cohort study.

BACKGROUND

Two-stage liver transplantation using small for size grafts should be a feasible procedure with lower morbidity and mortality rates. Retrospective cohort study between 2015 and 2022 with multicenter experience. Twenty-three resection and partial liver transplantation with delayed total hepatectomy procedures for noncirrhotic indications were performed in 6 European centers (20 with grafts from living donors and 3 after deceased donation). Procedure's feasibility, graft volumetric changes, morbidity, and mortality of donor and recipient were explored.

RESULTS

There was a low donor morbidity (4.3%) in our cohort. Hypertrophy of the graft was rapid (mean graft volume increases 107% between both stages) and offered the opportunity for remnant hepatectomy after a median of 14 days. In all cases, portomesenteric flow was routed to the graft by right remnant portal vein ligation. Portal vein inflow modulation to alleviate transient harmful portal hypertension was not needed in any case. Early postoperative mortality (4.3%) of the recipients were low. Ten patients suffered from complications ≥IIIb according to the Clavien-Dindo classification.

CONCLUSIONS

Two-stage liver transplantation is a feasible option for noncirrhotic patients allowing the safe use of small for size grafts and could possibly be extended with caution to liver diseases with portal hypertension and cirrhosis. The resection and partial liver transplantation with delayed total hepatectomy technique might be a viable option for expanding the donor pool given the current organ shortage especially for low-model of end stage liver disease patients.

Liver scaffolds obtained by decellularization: A transplant perspective in liver bioengineering

Liver transplantation is the only definitive treatment for many diseases that affect this organ, however, its quantity and viability are reduced. The study of liver scaffolds based on an extracellular matrix is a tissue bioengineering strategy with great application in regenerative medicine. Collectively, recent studies suggest that liver scaffold transplantation may assist in reestablishing hepatic function in preclinical diseased animals, which represents a great potential for application as a treatment for patients with liver disease in the future. This review focuses on useful strategies to promote liver scaffold transplantation and the main open questions about this context. We outline the current knowledge about ex vivo bioengineered liver transplantation, including the surgical techniques, recipient survival time, scaffold preparation before transplantation, and liver disease models. We also highlight the current limitations and future directions regarding in vivo bioengineering techniques.

A novel bioscaffold with naturally-occurring extracellular matrix promotes hepatocyte survival and vessel patency in mouse models of heterologous transplantation

BACKGROUND

Naïve decellularized liver scaffold (nDLS)-based tissue engineering has been impaired by the lack of a suitable extracellular matrix (ECM) to provide "active micro-environmental" support.

AIM

The present study aimed to examine whether a novel, regenerative DLS (rDLS) with an active ECM improves primary hepatocyte survival and prevents thrombosis.

METHODS

rDLS was obtained from a 30-55% partial hepatectomy that was maintained in vivo for 3-5 days and then perfused with detergent in vitro. Compared to nDLS generated from normal livers, rDLS possesses bioactive molecules due to the regenerative period in vivo. Primary mouse hepatocyte survival was evaluated by staining for Ki-67 and Trypan blue exclusion. Thrombosis was assessed by immunohistochemistry and ex vivo diluted whole-blood perfusion. Hemocompatibility was determined by near-infrared laser-Doppler flowmetry and heterotopic transplantation.

RESULTS

After recellularization, rDLS contained more Ki-67-positive primary hepatocytes than nDLS. rDLS had a higher oxygen saturation and blood flow velocity and a lower expression of integrin αIIb and α4 than nDLS. Tumor necrosis factor-α, hepatocyte growth factor, interleukin-10, interleukin-6 and interleukin-1β were highly expressed throughout the rDLS, whereas expression of collagen-I, collagen-IV and thrombopoietin were lower in rDLS than in nDLS. Improved blood vessel patency was observed in rDLS both in vitro and in vivo. The results in mice were confirmed in large animals (pigs).

CONCLUSION

rDLS is an effective DLS with an "active microenvironment" that supports primary hepatocyte survival and promotes blood vessel patency. This is the first study to demonstrate a rDLS with a blood microvessel network that promotes hepatocyte survival and resists thrombosis.

Auxiliary Partial Orthotopic Living Liver Transplant for Wilson Disease

Wilson disease is a genetic disease involving copper metabolism disturbances that result in copper accumulations, especially in the liver and brain. Wilson disease can be treated with pharmacologic agents, such as chelators that induce urinary excretion of copper or zinc salts that inhibit copper absorption in the digestive tract. Liver transplant is the only treatment option for Wilson disease when liver failure has occurred. In some patients, that is, in those with Child-Pugh A score, neurologic disease can be seen without hepatic failure. Our recommendation is for these patients to have auxiliary partial orthotopic liver transplant. Here, we present a 36-year-old male patient with neurologic disease associated with Wilson disease who had successful related living-donor auxiliary partial orthotopic liver transplant using a left lobe. The patient, as a result of neurologic symptoms that included tremor walking and speaking problems and low serum ceruloplasmin level of 7 mg/dL, was diagnosed with Wilson disease, and a liver biopsy was performed. Chronic necroinflammatory disease activity was 4/18, and the patient received chelation treatment. His hepatic functions were normal. The donor was the patient's 57-year-old father whose liver function tests were also normal. The graft-to-recipient weight ratio was 1% using a left lobe graft. After transplant, serum ceruloplasmin levels on day 15 and month 1 were 14 and 19 mg/dL. At month 1, liver function tests were normal. Doppler ultrasonography showed normal vascular flow of the native liver and the graft. The patient's neurologic symptoms were progressively reduced. Progressive neurologic deterioration with no hepatic insufficiency is considered a suitable indication for auxiliary partial orthotopic liver transplant; this procedure is suggested before the neurologic and liver failure symptoms of Wilson disease occur.

Wilson's Disease in China

Wilson's disease (WD) is an autosomal recessive disorder of copper metabolism. Its incidence is higher in China than in western countries. ATP7B is the causative gene and encodes a P-type ATPase, which participates in the synthesis of holoceruloplasmin and copper excretion. Disease-causing variants of ATP7B disrupt the normal structure or function of the enzyme and cause copper deposition in multiple organs, leading to diverse clinical manifestations. Given the variety of presentations, misdiagnosis is not rare. Genetic diagnosis plays an important role and has gradually become a routine test in China. The first Chinese spectrum of disease-causing mutations of ATP7B has been established. As a remediable hereditary disorder, most WD patients have a good prognosis with an early diagnosis and chelation treatment. However, clinical trials are relatively few in China, and most treatments are based on the experience of experts and evidences from other countries. It is necessary to study and develop appropriate regimens specific for Chinese WD patients.