No country for old livers? Examining and optimizing the utilization of elderly liver grafts.

Of the 1.6 million patients >70 years of age who died of stroke since 2002, donor livers were retrieved from only 2402 (0.15% yield rate). Despite reports of successful liver transplantation (LT) with elderly grafts (EG), advanced donor age is considered a risk for poor outcomes. Centers for Medicare and Medicaid Services definitions of an "eligible death" for donation excludes patients >70 years of age, creating disincentives to donation. We investigated utilization and outcomes of recipients of donors >70 through analysis of a United Network for Organ Sharing Standard Transplant Analysis and Research-file of adult LTs from 2002 to 2014. Survival analysis was conducted using Kaplan-Meier curves, and Cox regression was used to identify factors influencing outcomes of EG recipients. Three thousand one hundred four livers from donors >70, ≈40% of which were used in 2 regions: 2 (520/3104) and 9 (666/3104). Unadjusted survival was significantly worse among recipients of EG compared to recipients of younger grafts (P < .0001). Eight independent negative predictors of survival in recipients of EG were identified on multivariable analysis. Survival of low-risk recipients who received EG was significantly better than survival of recipients of younger grafts (P = .04). Outcomes of recipients of EG can therefore be optimized to equal outcomes of younger grafts. Given the large number of stroke deaths in patients >70 years of age, the yield rate of EGs can be maximized and disincentives removed to help resolve the organ shortage crisis.

Human immunology studies using organ donors: Impact of clinical variations on immune parameters in tissues and circulation.

Organ donors are sources of physiologically healthy organs and tissues for life-saving transplantation, and have been recently used for human immunology studies which are typically confined to the sampling of peripheral blood. Donors comprise a diverse population with different causes of death and clinical outcomes during hospitalization, and the effects of such variations on immune parameters in blood and tissues are not known. We present here a coordinate analysis of innate and adaptive immune components in blood, lymphoid (bone marrow, spleen, lymph nodes), and mucosal (lungs, intestines) sites from a population of brain-dead organ donors (2 months-93 years; n = 291) across eight clinical parameters. Overall, the blood of donors exhibited similar monocyte and lymphocyte content and low serum levels of pro-inflammatory cytokines as healthy controls; however, donor blood had increased neutrophils and serum levels of IL-8, IL-6, and MCP-1 which varied with cause of death. In tissues, the frequency and composition of monocytes, neutrophils, B lymphocytes and T cell subsets in lymphoid or mucosal sites did not vary with clinical state, and was similar in donors independent of the extent of clinical complications. Our results reveal that organ donors maintain tissue homeostasis, and are a valuable resource for fundamental studies in human immunology.

Results of gal-knockout porcine thymokidney xenografts.

Clinical transplantation for the treatment of end-stage organ disease is limited by a shortage of donor organs. Successful xenotransplantation could immediately overcome this limitation. The development of homozygous alpha1,3-galactosyltransferase knockout (GalT-KO) pigs removed hyperacute rejection as the major immunologic hurdle to xenotransplantation. Nevertheless, GalT-KO organs stimulate robust immunologic responses that are not prevented by immunosuppressive drugs. Murine studies show that recipient thymopoiesis in thymic xenografts induces xenotolerance. We transplanted life-supporting composite thymokidneys (composite thymus and kidneys) prepared in GalT-KO miniature swine to baboons in an attempt to induce tolerance in a preclinical xenotransplant model. Here, we report the results of seven xenogenic thymokidney transplants using a steroid-free immunosuppressive regimen that eliminated whole-body irradiation in all but one recipient. The regimen resulted in average recipient survival of over 50 days. This was associated with donor-specific unresponsiveness in vitro and early baboon thymopoiesis in the porcine thymus tissue of these grafts, suggesting the development of T-cell tolerance. The kidney grafts had no signs of cellular infiltration or deposition of IgG, and no grafts were lost due to rejection. These results show that xenogeneic thymus transplantation can support early primate thymopoiesis, which in turn may induce T-cell tolerance to solid organ xenografts.

Nonspecific ulcers of the colon.

Nonspecific colonic ulcers (NSCUs) are rare and potentially life-threatening lesions of unknown etiology; the diagnosis is based on histologic findings showing nonspecific inflammatory changes. The condition's variable symptoms can include nonspecific abdominal discomfort, gastrointestinal bleeding, perforation, and peritonitis. Radiologic imaging can be helpful in locating the lesions, but colonoscopy facilitates early definitive diagnosis and aggressive treatment. The potential of NSCUs to recur is currently unknown, and morbidity rates remain high. Long-term colonoscopic follow-up may improve the prognosis.