Dietary Inulin to Improve SARS-CoV-2 Vaccine Response in Kidney Transplant Recipients: The RIVASTIM-Inulin Randomised Controlled Trial.

Kidney transplant recipients are at an increased risk of hospitalisation and death from SARS-CoV-2 infection, and standard two-dose vaccination schedules are typically inadequate to generate protective immunity. Gut dysbiosis, which is common among kidney transplant recipients and known to effect systemic immunity, may be a contributing factor to a lack of vaccine immunogenicity in this at-risk cohort. The gut microbiota modulates vaccine responses, with the production of immunomodulatory short-chain fatty acids by bacteria such as Bifidobacterium associated with heightened vaccine responses in both observational and experimental studies. As SCFA-producing populations in the gut microbiota are enhanced by diets rich in non-digestible fibre, dietary supplementation with prebiotic fibre emerges as a potential adjuvant strategy to correct dysbiosis and improve vaccine-induced immunity. In a randomised, double-bind, placebo-controlled trial of 72 kidney transplant recipients, we found dietary supplementation with prebiotic inulin for 4 weeks before and after a third SARS-CoV2 mRNA vaccine to be feasible, tolerable, and safe. Inulin supplementation resulted in an increase in gut Bifidobacterium, as determined by 16S RNA sequencing, but did not increase in vitro neutralisation of live SARS-CoV-2 virus at 4 weeks following a third vaccination. Dietary fibre supplementation is a feasible strategy with the potential to enhance vaccine-induced immunity and warrants further investigation.

International Travel for Organ Transplantation: A Survey of Professional Experiences and Attitudes Toward Data Collection and Reporting.

Background: Lack of data regarding international travel for organ transplantation (ITOT) hampers efforts to evaluate, understand, and respond to trends in ITOT activities, such as those suggestive of organ trafficking or "transplant tourism." This study aimed to assess transplant professionals' experience of ITOT and their attitudes toward reporting ITOT data to a global registry. Methods: An international cross-sectional anonymous survey of transplant professionals was conducted online (from October to December 2022). The English language questionnaire assessed professional experiences in providing care to individuals who had traveled to or from a country for living donation or transplantation, and attitudes toward reporting of ITOT data. Data were analyzed with descriptive statistics. Results: Two hundred thirty-nine individuals from 68 countries completed the entire questionnaire, of whom 79% had provided care for ≥1 patient who had traveled internationally for donation or transplantation. Of these, 60.8% of individuals (n = 115) had cared for ≥1 person who engaged in ITOT between 2019 and 2022, with the most recent case experiences involving 89 countries and 157 unique routes of international travel. Predominant concerns regarding reporting of ITOT data to a global registry related to prevention of harm and protection of patient privacy; most (52.7%; n = 126) respondents expressed a preference for anonymous reporting of ITOT data. Conclusions: ITOT is a global phenomenon and transplant professionals' experience with ITOT cases is more common than anticipated. Systems for the collection of ITOT activity data should be carefully designed to address potential ethical concerns of transplant professionals which may influence reporting practices.

Inherited C-terminal TREX1 variants disrupt homology-directed repair to cause senescence and DNA damage phenotypes in Drosophila, mice, and humans.

Age-related microangiopathy, also known as small vessel disease (SVD), causes damage to the brain, retina, liver, and kidney. Based on the DNA damage theory of aging, we reasoned that genomic instability may underlie an SVD caused by dominant C-terminal variants in TREX1, the most abundant 3'-5' DNA exonuclease in mammals. C-terminal TREX1 variants cause an adult-onset SVD known as retinal vasculopathy with cerebral leukoencephalopathy (RVCL or RVCL-S). In RVCL, an aberrant, C-terminally truncated TREX1 mislocalizes to the nucleus due to deletion of its ER-anchoring domain. Since RVCL pathology mimics that of radiation injury, we reasoned that nuclear TREX1 would cause DNA damage. Here, we show that RVCL-associated TREX1 variants trigger DNA damage in humans, mice, and Drosophila, and that cells expressing RVCL mutant TREX1 are more vulnerable to DNA damage induced by chemotherapy and cytokines that up-regulate TREX1, leading to depletion of TREX1-high cells in RVCL mice. RVCL-associated TREX1 mutants inhibit homology-directed repair (HDR), causing DNA deletions and vulnerablility to PARP inhibitors. In women with RVCL, we observe early-onset breast cancer, similar to patients with BRCA1/2 variants. Our results provide a mechanistic basis linking aberrant TREX1 activity to the DNA damage theory of aging, premature senescence, and microvascular disease.

Transplantation in the Context of Migration and Refugees: A Summary of the DICG and TTS Ethics Committee Workshop, Buenos Aires, Argentina, September 2022.

Global conflicts and humanitarian crises have resulted in an unprecedented number of refugees and migrants. This challenges the limited resources of health care systems and jeopardizes the availability of transplant care for these deserving migrants and refugees. This was the basis for a workshop held during the Congress of the Transplantation Society (Buenos Aires, 2022). We elaborate on the proceedings of the workshop entitled "Transplantation in the Context of Migration and Refugees," organized by the Ethics Committee of The Transplantation Society and Declaration of Istanbul Custodian Group. Transplant providers from around the world shared strategies of how each region has responded to providing access to care for refugees and migrants in need of transplant services. The potential exploitation of this vulnerable group leading to illicit organ removal was addressed for each region. The Transplantation Society, Declaration of Istanbul Custodian Group, and global transplant community should continue to focus on the status of refugees and migrants and collaborate on strategies to provide access to transplant care for this deserving population. Global cooperation will be essential to provide vigilant oversight to prevent exploitation of this vulnerable population.

Kidney transplantation in people living with human immunodeficiency virus: An overview of the Australian experience.

Kidney transplantation in people living with HIV (PLWHIV) is occurring with increasing frequency. Limited international data suggest comparable patient and graft survival in kidney transplant recipients with and without HIV. All PLWHIV aged ≥18 years who received a kidney transplant between 2000 and 2020 were identified by retrospective data initially extracted from Australia and New Zealand Dialysis and Transplant Registry (ANZDATA), with additional HIV-specific clinical data extracted from linked local health-care records. Twenty-five PLWHIV and kidney failure received their first kidney transplant in Australia between January 2000 and December 2020. Majority were male (85%), with median age 54 years (interquartile range, IQR 43-57). Focal segmental glomerulosclerosis was the most common primary kidney disease (20%), followed by polycystic kidney disease (16%). 80% of patients underwent induction with basiliximab and none with anti-thymocyte globulin (ATG). Participants were followed for median time of 3.5 years (IQR 2.0-6.5). Acute rejection occurred in 24% of patients. Two patients lost their allografts and three died. Virological escape occurred in 28% of patients, with a maximum viral load of 190 copies/mL. In conclusion, kidney transplantation in PLWHIV in Australia is occurring with increasing frequency. Acute rejection is more common than in Australia's general transplant population, but this does not appear to be associated with higher rates of graft failure or mortality out to four years.

Balanced crystalloid solution versus saline in deceased donor kidney transplantation (BEST-Fluids): a pragmatic, double-blind, randomised, controlled trial.

BACKGROUND: Delayed graft function (DGF) is a major adverse complication of deceased donor kidney transplantation. Intravenous fluids are routinely given to patients receiving a transplant to maintain intravascular volume and optimise graft function. Saline (0·9% sodium chloride) is widely used but might increase the risk of DGF due to its high chloride content. We aimed to test our hypothesis that using a balanced low-chloride crystalloid solution (Plasma-Lyte 148) instead of saline would reduce the incidence of DGF. METHODS: BEST-Fluids was a pragmatic, registry-embedded, multicentre, double-blind, randomised, controlled trial at 16 hospitals in Australia and New Zealand. Adults and children of any age receiving a deceased donor kidney transplant were eligible; those receiving a multi-organ transplant or weighing less than 20 kg were excluded. Participants were randomly assigned (1:1) using an adaptive minimisation algorithm to intravenous balanced crystalloid solution (Plasma-Lyte 148) or saline during surgery and up until 48 h after transplantation. Trial fluids were supplied in identical bags and clinicians determined the fluid volume, rate, and time of discontinuation. The primary outcome was DGF, defined as receiving dialysis within 7 days after transplantation. All participants who consented and received a transplant were included in the intention-to-treat analysis of the primary outcome. Safety was analysed in all randomly assigned eligible participants who commenced surgery and received trial fluids, whether or not they received a transplant. This study is registered with Australian New Zealand Clinical Trials Registry, (ACTRN12617000358347), and ClinicalTrials.gov (NCT03829488). FINDINGS: Between Jan 26, 2018, and Aug 10, 2020, 808 participants were randomly assigned to balanced crystalloid (n=404) or saline (n=404) and received a transplant (512 [63%] were male and 296 [37%] were female). One participant in the saline group withdrew before 7 days and was excluded, leaving 404 participants in the balanced crystalloid group and 403 in the saline group that were included in the primary analysis. DGF occurred in 121 (30%) of 404 participants in the balanced crystalloid group versus 160 (40%) of 403 in the saline group (adjusted relative risk 0·74 [95% CI 0·66 to 0·84; p<0·0001]; adjusted risk difference 10·1% [95% CI 3·5 to 16·6]). In the safety analysis, numbers of investigator-reported serious adverse events were similar in both groups, being reported in three (<1%) of 406 participants in the balanced crystalloid group versus five (1%) of 409 participants in the saline group (adjusted risk difference -0·5%, 95% CI -1·8 to 0·9; p=0·48). INTERPRETATION: Among patients receiving a deceased donor kidney transplant, intravenous fluid therapy with balanced crystalloid solution reduced the incidence of DGF compared with saline. Balanced crystalloid solution should be the standard-of-care intravenous fluid used in deceased donor kidney transplantation. FUNDING: Medical Research Future Fund and National Health and Medical Research Council (Australia), Health Research Council (New Zealand), Royal Australasian College of Physicians, and Baxter.

Robust and prototypical immune responses toward COVID-19 vaccine in First Nations peoples are impacted by comorbidities.

High-risk groups, including Indigenous people, are at risk of severe COVID-19. Here we found that Australian First Nations peoples elicit effective immune responses to COVID-19 BNT162b2 vaccination, including neutralizing antibodies, receptor-binding domain (RBD) antibodies, SARS-CoV-2 spike-specific B cells, and CD4+ and CD8+ T cells. In First Nations participants, RBD IgG antibody titers were correlated with body mass index and negatively correlated with age. Reduced RBD antibodies, spike-specific B cells and follicular helper T cells were found in vaccinated participants with chronic conditions (diabetes, renal disease) and were strongly associated with altered glycosylation of IgG and increased interleukin-18 levels in the plasma. These immune perturbations were also found in non-Indigenous people with comorbidities, indicating that they were related to comorbidities rather than ethnicity. However, our study is of a great importance to First Nations peoples who have disproportionate rates of chronic comorbidities and provides evidence of robust immune responses after COVID-19 vaccination in Indigenous people.

International Society of Nephrology first consensus guidance for preclinical animal studies in translational nephrology.

Preclinical tests in animal models are key steps in early drug development. Consequently, the International Society of Nephrology held a consensus meeting that connected experts in the global kidney community in order to provide guidance on optimal management of translational animal studies for the development of new drugs to treat kidney disease, entitled "TRANSFORM; TRAnslational Nephrology Science FOR new Medications." The meeting covered various themes, including the following: (i) selection of disease model; (ii) pharmacokinetics; (iii) interventions in late preclinical models; (iv) choice of animal; (v) statistical power; (vi) organoids and organ-on-a-chip models; and (vii) reporting of results. This guidance is the first to be provided on the optimal conduct of translational animal studies for the development of new drugs to treat kidney disease. These recommendations are designed to accelerate development of new drugs for efficacious treatment of kidney diseases, and to improve the prognosis and quality of life of patients with a variety of kidney diseases.

Intracutaneous Transplantation of Islets Within a Biodegradable Temporizing Matrix as an Alternative Site for Islet Transplantation.

Intrahepatic islet transplantation for type 1 diabetes is limited by the need for multiple infusions and poor islet viability posttransplantation. The development of alternative transplantation sites is necessary to improve islet survival and facilitate monitoring and retrieval. We tested a clinically proven biodegradable temporizing matrix (BTM), a polyurethane-based scaffold, to generate a well-vascularized intracutaneous "neodermis" within the skin for islet transplantation. In murine models, BTM did not impair syngeneic islet renal-subcapsular transplant viability or function, and it facilitated diabetes cure for over 150 days. Furthermore, BTM supported functional neonatal porcine islet transplants into RAG-1-/- mice for 400 days. Hence, BTM is nontoxic for islets. Two-photon intravital imaging used to map vessel growth through time identified dense vascular networks, with significant collagen deposition and increases in vessel mass up to 30 days after BTM implantation. In a preclinical porcine skin model, BTM implants created a highly vascularized intracutaneous site by day 7 postimplantation. When syngeneic neonatal porcine islets were transplanted intracutaneously, the islets remained differentiated as insulin-producing cells, maintained normal islet architecture, secreted c-peptide, and survived for over 100 days. Here, we show that BTM facilitates formation of an islet-supportive intracutaneous neodermis in a porcine preclinical model, as an alternative islet-transplant site. ARTICLE HIGHLIGHTS: Human and porcine pancreatic islets were transplanted into a fully vascularized biodegradable temporizing matrix (Novosorb) that creates a unique intracutaneous site outside of the liver in a large-animal preclinical model. The intracutaneous prevascularized site supported pancreatic islet survival for 3 months in a syngeneic porcine-transplant model. Pancreatic (human and porcine) islet survival and function were demonstrated in an intracutaneous site outside of the liver for the first time in a large-animal preclinical model.

Do patient decision aids help people who are facing decisions about solid organ transplantation? A systematic review.

BACKGROUND: Decisions about solid organ transplantation are complex. Patient decision aids (PDAs) enhance traditional education, by improving knowledge and supporting patients to align their values with treatments. There are increasing numbers of transplantation PDAs, however, it is unclear whether these are effective. We conducted a systematic review of studies assessing the impact of PDA use in transplantation. METHODS: We searched the Cochrane Register of Controlled Trials, CINAHL, EMBASE, MEDLINE, and PsycINFO databases from database inception to October 26, 2020. We included primary studies of solid organ transplantation PDAs defined by the International Patient Decision Aids Standards. All comparators and reported outcomes were included. Mean difference in knowledge (before vs. after) was standardized on a 100-point scale. Pooled-effect for PDAs was calculated and compared to the standard of care for randomized controlled trials (RCTs) and meta-analyzed using random effects. Analysis of all other outcomes was limited due to heterogeneity (PROSPERO registration, CRD42020215940). RESULTS: Seven thousand four hundred and sixty-three studies were screened, 163 underwent full-text review, and 15 studies with 4278 participants were included. Nine studies were RCTs. Seven RCTs assessed knowledge; all demonstrated increased knowledge with PDA use (mean difference, 8.01;95%CI 4.69-11.34, p < .00001). There were many other outcomes, including behavior and acceptability, but these were too heterogenous and infrequently assessed for meaningful synthesis. CONCLUSIONS: This review found that PDAs increase knowledge compared to standard education, though the effect size is small. PDAs are mostly considered acceptable; however, it is difficult to determine whether they improve other decision-making components due to the limited evidence about non-knowledge-based outcomes.

Future Directions for Adrenal Insufficiency: Cellular Transplantation and Genetic Therapies.

Primary adrenal insufficiency (PAI) occurs in 1 in 5 to 7000 adults. Leading etiologies are autoimmune adrenalitis in adults and congenital adrenal hyperplasia (CAH) in children. Oral replacement of cortisol is lifesaving, but poor quality of life, repeated adrenal crises, and dosing uncertainty related to lack of a validated biomarker for glucocorticoid sufficiency persists. Adrenocortical cell therapy and gene therapy may obviate many of the shortcomings of adrenal hormone replacement. Physiological cortisol secretion regulated by pituitary adrenocorticotropin could be achieved through allogeneic adrenocortical cell transplantation, production of adrenal-like steroidogenic cells from either stem cells or lineage conversion of differentiated cells, or for CAH, gene therapy to replace or repair a defective gene. The adrenal cortex is a high-turnover organ and thus failure to incorporate progenitor cells within a transplant will ultimately result in graft exhaustion. Identification of adrenocortical progenitor cells is equally important in gene therapy, for which new genetic material must be specifically integrated into the genome of progenitors to ensure a durable effect. Delivery of gene-editing machinery and a donor template, allowing targeted correction of the 21-hydroxylase gene, has the potential to achieve this. This review describes advances in adrenal cell transplants and gene therapy that may allow physiological cortisol production for children and adults with PAI.

COVID and the Kidney: An Update.

Coronavirus disease-2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2, has led to a global pandemic that continues to be responsible for ongoing health issues for people worldwide. Immunocompromised individuals such as kidney transplant recipients and dialysis patients have been and continue to be among the most affected, with poorer outcomes after infection, impaired response to COVID-19 vaccines, and protracted infection. The pandemic also has had a significant impact on patients with underlying chronic kidney disease (CKD), with CKD increasing susceptibility to COVID-19, risk of hospital admission, and mortality. COVID-19 also has been shown to lead to acute kidney injury (AKI) through both direct and indirect mechanisms. The incidence of COVID-19 AKI has been decreasing as the pandemic has evolved, but continues to be associated with adverse patient outcomes correlating with the severity of AKI. There is also increasing evidence examining the longer-term effect of COVID-19 on the kidney demonstrating continued decline in kidney function several months after infection. This review summarizes the current evidence examining the impact of COVID-19 on the kidney, covering both the impact on patients with CKD, including patients receiving kidney replacement therapy, in addition to discussing COVID-19 AKI.

Baseline Characteristics and Representativeness of Participants in the BEST-Fluids Trial: A Randomized Trial of Balanced Crystalloid Solution Versus Saline in Deceased Donor Kidney Transplantation.

Delayed graft function (DGF) is a major complication of deceased donor kidney transplantation. Saline (0.9% sodium chloride) is a commonly used intravenous fluid in transplantation but may increase the risk of DGF because of its high chloride content. Better Evidence for Selecting Transplant Fluids (BEST-Fluids), a pragmatic, registry-based, double-blind, randomized trial, sought to determine whether using a balanced low-chloride crystalloid solution (Plasma-Lyte 148) instead of saline would reduce DGF. We sought to evaluate the generalizability of the trial cohort by reporting the baseline characteristics and representativeness of the trial participants in detail. Methods: We compared the characteristics of BEST-Fluids participants with those of a contemporary cohort of deceased donor kidney transplant recipients in Australia and New Zealand using data from the Australia and New Zealand Dialysis and Transplant Registry. To explore potential international differences, we compared trial participants with a cohort of transplant recipients in the United States using data from the Scientific Registry of Transplant Recipients. Results: During the trial recruitment period, 2373 deceased donor kidney transplants were performed in Australia and New Zealand; 2178 were eligible' and 808 were enrolled in BEST-Fluids. Overall, trial participants and nonparticipants were similar at baseline. Trial participants had more coronary artery disease (standardized difference [d] = 0.09; P = 0.03), longer dialysis duration (d = 0.18, P < 0.001), and fewer hypertensive (d = -0.11, P = 0.03) and circulatory death (d = -0.14, P < 0.01) donors than nonparticipants. Most key characteristics were similar between trial participants and US recipients, with moderate differences (|d| ≥ 0.2; all P < 0.001) in kidney failure cause, diabetes, dialysis duration, ischemic time, and several donor risk predictors, likely reflecting underlying population differences. Conclusions: BEST-Fluids participants had more comorbidities and received slightly fewer high-risk deceased donor kidneys but were otherwise representative of Australian and New Zealand transplant recipients and were generally similar to US recipients. The trial results should be broadly applicable to deceased donor kidney transplantation practice worldwide.