Immunoproteasome inhibition reduces donor specific antibody production and cardiac allograft vasculopathy in a mouse heart transplantation model.

Objective: Cardiac Allograft Vasculopathy (CAV), a process of vascular damage accelerated by antibody-mediated rejection (AMR), is one of the leading causes of cardiac transplant failure. Proteasome inhibitors (PIs) are utilized to treat AMR, however PI-associated toxicity limits their therapeutic utility. Novel immunoproteasome inhibitors (IPIs) have higher specificity for immune cells and have not been investigated for AMR in cardiac transplant patients.

Student and Attending Preceptor Perceptions of Longitudinal Clinic as a Surgical Education and Assessment Tool.

Introduction: As undergraduate medical education becomes increasingly longitudinal, particular attention is needed to maintain sufficient exposure to surgical disciplines. While traditional medical student clerkships are isolated 4 to 8-wk blocks on a single service, one unique adjunct to the traditional clerkship model is the continuity clinic (CC): a weekly longitudinal requirement that occurs either during the traditional clerkship or following clerkships while conducting independent research. This study compares attending surgeon and medical student perceptions of important characteristics in evaluating a student in CC and the perceived utility of this experience in assessment and preparation for subinternships.

Is Allosensitization Detrimental to Pig Organ Xenotransplantation, and Is Xenosensitization Detrimental to Subsequent Organ Allotransplantation? A Debate Organized by the International Xenotransplantation Association (IXA).

This report summarizes the content of a debate sponsored by eGenesis Bio, organized by the International Xenotransplantation Association (IXA), and attended by more than 150 delegates in the context of the IPITA-IXA-CTRMS Joint Congress held in San Diego in October 2023. The debate centered around two important immunological topics relating to xenotransplantation. The first was a debate relating to the statement that "HLA-sensitized patients are at higher risk for rejecting a pig xenograft.

Animal Models Within Surgical Simulation: A Novel Approach to the 3 Rs.

Introduction: Development of technical skills is a vital component of surgical residency. The use of animal tissues for operative simulation leads to both the loss of animal life and financial costs for the institution. We hypothesized that maximizing tissue use from investigational large animal models after euthanasia could reduce loss of animal life and institutional costs by replacing commercially purchased tissues.

Allosensitisation in NHP results in cross-reactive anti-SLA antibodies not detected by a lymphocyte-based flow cytometry crossmatch.

Xenotransplantation is a potential option for individuals for whom an acceptable human allograft is unavailable. Individuals with broadly reactive HLA antibodies due to prior exposure to foreign HLA are potential candidates for a clinical xenotransplant trial. It remains controversial if allosensitisation results in the development of cross-reactive antibodies against SLA.

Prior Teaching Experience and Barriers to Effective Resident Teaching: A Cross-Sectional Study.

Introduction: Resident physicians play an important role in teaching the next generation of health-care providers, yet limited research has explored factors influencing effective teaching, such as preresidency experiences or barriers within residency. This study examines residents' prior teaching experience, its correlation with teaching attitudes, and identifies potential barriers to sustained teaching engagement.

Methods: This cross-sectional study surveyed residents across multiple specialties at a single academic center.

Subnormothermic Oxygenated Machine Perfusion (24 h) in DCD Kidney Transplantation.

Background: Ex vivo kidney perfusion is an evolving platform that demonstrates promise in preserving and rehabilitating the kidney grafts. Despite this, there is little consensus on the optimal perfusion conditions. Hypothermic perfusion offers limited functional assessment, whereas normothermic perfusion requires a more complex mechanical system and perfusate.

The Role of Autophagy in Vascular Endothelial Cell Health and Physiology.

Autophagy is a highly conserved cellular recycling process which enables eukaryotes to maintain both cellular and overall homeostasis through the catabolic breakdown of intracellular components or the selective degradation of damaged organelles. In recent years, the importance of autophagy in vascular endothelial cells (ECs) has been increasingly recognized, and numerous studies have linked the dysregulation of autophagy to the development of endothelial dysfunction and vascular disease. Here, we provide an overview of the molecular mechanisms underlying autophagy in ECs and our current understanding of the roles of autophagy in vascular biology and review the implications of dysregulated autophagy for vascular disease.

Late graft failure of pig-to-rhesus renal xenografts has features of glomerulopathy and recipients have anti-swine leukocyte antigen class I and class II antibodies.

Prolonged survival in preclinical renal xenotransplantation demonstrates that early antibody mediated rejection (AMR) can be overcome. It is now critical to evaluate and understand the pathobiology of late graft failure and devise new means to improve post xenograft outcomes. In renal allotransplantation the most common cause of late renal graft failure is transplant glomerulopathy-largely due to anti-donor MHC antibodies, particularly anti-HLA DQ antibodies.

The Surgical Clerkship in the COVID Era: A Natural Language Processing and Thematic Analysis.

Introduction: Responses to COVID-19 within medical education prompted significant changes to the surgical clerkship. We analyzed the changes in medical student end of course feedback before and after the COVID-19 outbreak.

Methods: Postclerkship surveys from 2017 to 2022 were analyzed including both Likert scale data and free text, excluding the COVID outbreak year 2019-2020.

Normothermic Preservation of the Intestinal Allograft.

Intestinal allotransplantation was first described in the 1960s and successfully performed in the 1980s. Since that time, less progress has been made in the preservation of the allograft before transplantation and static cold storage remains the current standard. Normothermic machine perfusion represents an opportunity to simultaneously preserve, assess, and recondition the organ for transplantation and improve the procurement radius for allografts.

Contemporary trends and outcomes after liver transplantation and resection for intrahepatic cholangiocarcinoma.

Background: Liver transplantation (LT) has been shown to be superior to resection in highly selected patients with perihilar cholangiocarcinoma (CCA), yet has traditionally been contraindicated for intrahepatic CCA (iCCA). Herein, we aimed to examine contemporary trends and outcomes for surgical resection and LT for iCCA.

Methods: The National Cancer Database was queried for patients presenting with stage I-III iCCA between 2010 and 2018 who underwent resection or LT.

A pig kidney supporting human physiology.

Because of the global shortage of donor kidneys, xenotransplantation emerges as a potential solution for individuals with kidney failure who face challenges in securing a suitable donor kidney. A study featured in this month's issue of Kidney International assesses the kidney physiology of a porcine kidney transplanted into a brain-dead human with kidney failure, demonstrating life-sustaining physiological function for 7 days. Together with preclinical nonhuman primate studies, decedent models provide complementary data for development of clinical kidney xenotransplantation.

The Young Investigator Committee of the International Xenotransplantation Association-Perspective of advancements in the field in 2023.

The 2023 IXA conference, hosted in San Diego, CA, brimmed with excitement against the backdrop of recent innovations in both the pre-clinical and clinical realms with several first-in-human applications of xenotransplantation. The theme, "Pigs are flying," alluded to the adage that xenotransplantation would only become a clinical reality "when pigs fly," suggesting a day that might never come. The event witnessed significant attendance, with 600 participants-the highest in the history of an IXA-IPITA joint congress.

The impact of IdeS (imlifidase) on allo-specific, xeno-reactive, and protective antibodies in a sensitized rhesus macaque model.

Background: Highly sensitized patients face many barriers to kidney transplantation, including higher rates of antibody-mediated rejection after HLA-incompatible transplant. IdeS, an endopeptidase that cleaves IgG nonspecifically, has been trialed as desensitization prior to kidney transplant, and successfully cleaves donor-specific antibody (DSA), albeit with rebound.

Methods: IdeS was generated and tested (2 mg/kg, IV) in two naïve and four allosensitized nonhuman primates (NHP).

Surgical Residents as Clerkship Scholars May Improve Student Perception of the Surgery Clerkship.

Introduction: The surgical clerkship is a formative experience in the medical school curriculum and can leave a lasting impression on students' perception of surgery. Given the historical negative stereotypes of surgeons, the clerkship represents an opportunity to impact students in a meaningful way.

Methods: Our institution developed a program in which research residents can serve as junior clerkship coordinators and educators; working closely with medical students on their surgery clerkship.

The Association Between Altmetric Attention Scores and Public Engagement in the Medical Literature.

Introduction: With the advent of social media and the associated increase in connectivity between scientists and the lay public, the Altmetric Attention Score has been created as a way to measure these interactions between scholarly publications and media dissemination. Little is known, however, whether these types of media exchanges measured by Altmetrics may serve as a proxy for public engagement. As such, we have sought to determine whether or not an association exists between Altmetric scores and public engagement, as measured by article citation in a health policy document.

The anti-CD40L monoclonal antibody AT-1501 promotes islet and kidney allograft survival and function in nonhuman primates.

Prior studies of anti-CD40 ligand (CD40L)-based immunosuppression demonstrated effective prevention of islet and kidney allograft rejection in nonhuman primate models; however, clinical development was halted because of thromboembolic complications. An anti-CD40L-specific monoclonal antibody, AT-1501 (Tegoprubart), was engineered to minimize risk of thromboembolic complications by reducing binding to Fcγ receptors expressed on platelets while preserving binding to CD40L. AT-1501 was tested in both a cynomolgus macaque model of intrahepatic islet allotransplantation and a rhesus macaque model of kidney allotransplantation.

A novel low-cost model of superficial abscess for trainee education in incision and drainage.

Background: Proficiency in ultrasound usage is quickly becoming an expectation in multiple residency programs: emergency medicine, obstetrics-gynecology, surgery, and internal medicine. There is a lack of affordable training devices for ultrasound training and identification of superficial fluid collections. We sought to develop a model for trainee education in ultrasound usage, identification of superficial fluid collection, aspiration, and incision & drainage (I&D).

Attitudes of patients with renal disease on xenotransplantation: A systematic review.

Background: Recent years have seen major advancements in xenotransplantation: the first pig-to-human heart transplant, the development of a brain-dead recipient model for kidney xenotransplantation, and the registration of the first xenokidney clinical trial. The attitudes of patients with kidney disease or transplants on xenotransplantation and an assessment of their reservations and considerations regarding the technology are crucial to successful clinical translation and eventual widespread implementation.

Methods: This systematic review was registered through PROSPERO (CRD42022344581) prior to initiation of the study and reported using the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines.

Complement-targeted therapies in kidney transplantation-insights from preclinical studies.

Aberrant activation of the complement system contributes to solid-organ graft dysfunction and failure. In kidney transplantation, the complement system is implicated in the pathogenesis of antibody- and cell-mediated rejection, ischemia-reperfusion injury, and vascular injury. This has led to the evaluation of select complement inhibitors (e.

A novel method for in vitro culture and expansion of nonhuman primate B cells.

Background: Given the role of B cells in sensitization and antibody-mediated rejection pathogenesis, the ability to identify, isolate, and study B cells in vitro is critical for understanding these processes and developing novel therapeutics. While in vivo nonhuman primate models have been used to this end, an in vitro nonhuman primate model of B cell activation and proliferation has not been developed.

Methods: CD20 B cells and CD3 T cells were isolated using magnetic bead separation from the peripheral blood of naive and skin allograft sensitized nonhuman primates.