Faculty Bibliography

OBJECTIVE:The aim of the study was to compare the short-term donor outcomes of laparoscopic left lateral sectionectomy (LLLS) for adult to child living donor liver transplantation (A-C LDLT) and laparoscopic donor nephrectomy (LDN). BACKGROUND:Although laparoscopy has become the standard approach in kidney donors, its use remains limited and controversial in LLS for A-C LDLT due to the lack of conclusive assessment of procedure-related morbidity. METHODS:From 2001 to 2014, 124 healthy donors undergoing laparoscopic LLLS for A-C LDLT at 5 tertiary referral centers in Europe, North America, and Asia, and 300 healthy donors undergoing LDN at 2 tertiary centers in Europe were retrospectively analyzed. The outcomes of LLLS were compared with those of LDN including the use of the comprehensive complication index (CCI). RESULTS:Although liver donors experienced significantly less overall (16.9% vs 31.7%, P = 0.002) and grade 1 to 2 (12.1% vs 24.7%, P = 0.004) complications than kidney donors, the rates of major complication (≥ grade 3) were similar between the 2 groups. In both groups, donors experiencing postoperative complications had similar CCI (19.3 vs 21.9 for liver and kidney donors, respectively, P = 0.29). After propensity score analysis allowing for matching donors on age, sex, and body mass index, the postoperative outcomes remained comparable between the 2 groups. CONCLUSION/CONCLUSIONS:Laparoscopic LLS for A-C LDLT yields at least similar short-term donor outcomes as LDN. These results provide the first validation for a laparoscopic donor hepatectomy and suggest that the laparoscopic approach should be considered a new standard practice for retrieval of left lateral section liver grafts as it is for kidney donation.

Living donor liver transplantation has failed to become a major means of transplantation in the United States, where <5% of the transplants are performed with living donors. At least 30% to 50% of the complications of donor hepatectomy appear to be related to abdominal wall trauma, including hernia, bowel obstruction, and chronic abdominal discomfort. We analyzed our experience with laparoscopically procured donor hepatectomy. We compared 22 full laparoscopic donor hepatectomies to 20 open/hybrid hepatectomies over an 11-year period. Donor and recipient demographics, complications, and graft and recipient outcomes were analyzed. All 22 laparoscopically procured liver allografts were transplanted successfully. The laparoscopically procured grafts took longer to procure (7 hours 58 minutes versus 6 hours 38 minutes; P < 0.001). The laparoscopically procured cases had lower blood loss (177.3 versus 3753 cc; P < 0.001), a shorter length of stay, and significantly reduced days off work (P = .01). The 1-year graft survival was not different (90% in the laparoscopic group and 85% in the open group; P = 0.70). The 1-year patient survival was not different (95% in the laparoscopic group and 85% in the open group; P = 0.32). There was a trend toward lower wound issues in the laparoscopic group, but this did not reach significance (the hybrid/open group had a 15% hernia rate versus 5% for the laparoscopic group). In experienced living donor centers, laparoscopic liver donation appears to be feasible for all pediatric recipients and some adult recipients. Outcomes for the recipients of laparoscopically procured grafts do not appear significantly different from outcomes with hybrid/open techniques.

BACKGROUND:Regulatory T cells (Treg) are being explored for their tolerance-inducing capabilities. Freezing and banking Treg for future use makes this strategy more clinically applicable. We aimed to devise an improved method of expanding and cryopreserving Treg to maximize yield, purity, and function for use in xenotransplantation. METHODS:cells were isolated by flow cytometric sorting and expanded for 26 days in culture with IL-2, anti-CD3 antibody, artificial APCs transfected with human CD58, CD32, and CD80, and rapamycin with weekly restimulations. Expanded Treg were frozen for 2 months then thawed and cultured for 48 hours in medium plus 1) no additives, 2) IL-2, 3) anti-CD3 antibody, 4) IL-2 + anti-CD3 antibody, and 5) IL-2 + anti-CD3 antibody + L cells. Phenotype and suppression were assessed after expansion, immediately after thawing, and after culturing. RESULTS:We expanded purified baboon Treg more than 10,000-fold. Expanded Treg exhibited excellent suppression in functional assays. Cryopreservation decreased suppressive function without changing phenotype, but increasing amounts of reactivation after thawing produced significantly better viability and suppressive function with a trend towards greater Treg purity. CONCLUSIONS:infusion should be possible.

UNLABELLED:Priority is given to patients with hepatocellular carcinoma (HCC) to receive liver transplants, potentially causing significant regional disparities in organ access and possibly outcomes in this population. Our aim was to assess these disparities by comparing outcomes in long waiting time regions (LWTR, regions 5 and 9) and short waiting time regions (SWTR regions 3 and 10) by analyzing the United Network for Organ Sharing (UNOS) database. We analyzed 6,160 HCC patients who received exception points in regions 3, 5, 9, and 10 from 2002 to 2012. Data from regions 5 and 9 were combined and compared to data from regions 3 and 10. Survival was studied in three patient cohorts: an intent-to-treat cohort, a posttransplant cohort, and a cohort examining overall survival in transplanted patients only (survival from listing to last posttransplant follow-up). Multivariate analysis and log-rank testing were used to analyze the data. Median time on the list in the LWTR was 7.6 months compared to 1.6 months for SWTR, with a significantly higher incidence of death on the waiting list in LWTR than in SWTR (8.4% versus 1.6%, P < 0.0001). Patients in the LWTR were more likely to receive loco-regional therapy, to have T3 tumors at listing, and to receive expanded-criteria donor (ECD) or donation after cardiac death (DCD) grafts than patients in the SWTR (P < 0.0001 for all). Survival was significantly better in the LWTR compared to the SWTR in all three cohorts (P < 0.0001 for all three survival points). Being listed/transplanted in an SWTR was an independent predictor of poor patient survival on multivariate analysis (P < 0.0001, hazard ratio = 1.545, 95% confidence interval 1.375-1.736). CONCLUSION/CONCLUSIONS:This study provides evidence that expediting patients with HCC to transplant at too fast a rate may adversely affect patient outcomes.

Intestinal transplantation is a well-accepted treatment for SBS. However, patients with SBS often have decreased abdominal capacity, which makes size-matching of donor organs more difficult, thus decreasing organ availability. Reported approaches for addressing this problem include surgically reducing the graft size, leaving an open abdomen for a prolonged period, and cotransplanting rectus fascia as a non-vascularized allograft. Each approach has significant disadvantages. There has been one previous report of tissue expanders used intra-abdominally and two reports of subcutaneous use to increase intra-abdominal capacity prior to transplantation. We report the first use of bi-planar expander placement for this purpose. In our case, a two-yr-old male child with SBS due to malrotation was treated with tissue expanders 10 months prior to intestinal transplantation, thus allowing transplantation of a larger graft with the ability to close the abdomen safely. There were no complications, and the patient is now doing well and tolerating diet off PN. The use of tissue expanders prior to intestinal transplantation is a promising approach for such patients and avoids the morbidity associated with other approaches. This approach requires a multidisciplinary effort by gastroenterology, transplant surgery, and plastic surgery teams.

The discrepancy between organ need and organ availability represents one of the major limitations in the field of transplantation. One possible solution to this problem is xenotransplantation. Research in this field has identified several obstacles that have so far prevented the successful development of clinical xenotransplantation protocols. The main immunologic barriers include strong T-cell and B-cell responses to solid organ and cellular xenografts. In addition, components of the innate immune system can mediate xenograft rejection. Here, we review these immunologic and physiologic barriers and describe some of the strategies that we and others have developed to overcome them. We also describe the development of two strategies to induce tolerance across the xenogeneic barrier, namely thymus transplantation and mixed chimerism, from their inception in rodent models through their current progress in preclinical large animal models. We believe that the addition of further beneficial transgenes to Gal knockout swine, combined with new therapies such as Treg administration, will allow for successful clinical application of xenotransplantation.

Delayed gastric emptying is a significant postoperative complication of living donor hepatectomy for liver transplantation and may require endoscopic or surgical intervention in severe cases. Although the mechanism of posthepatectomy delayed gastric emptying remains unknown, vagal nerve injury during intraoperative dissection and adhesion formation postoperatively between the stomach and cut liver surface are possible explanations. Here, we present the first reported case of delayed gastric emptying following fully laparoscopic hepatectomy for living donor liver transplantation. Additionally, we also present a case in which symptoms developed after open right hepatectomy, but for which dissection for left hepatectomy was first performed. Through our experience and these two specific cases, we favor a neurovascular etiology for delayed gastric emptying after hepatectomy.