First report of full colon transplantation as part of a visceral allograft.

Background: The inclusion of the colon as part of intestinal and multivisceral allografts has increased in the last decade.

Methods: We describe for the first time in the literature a full colon transplantation as a part of a visceral allograft. The new approach involves modifications of the procurement technique with preservation of all three visceral aortic branches and incorporation of the descending and sigmoid colon as a part of the allograft.

The Hydractinia cell atlas reveals cellular and molecular principles of cnidarian coloniality.

Coloniality is a widespread growth form in cnidarians, tunicates, and bryozoans, among others. Colonies function as single physiological units despite their modular structure of zooids and supporting tissues. A key question is how structurally and functionally distinct colony parts are generated.

NKG2D blockade impairs tissue-resident memory T cell accumulation and reduces chronic lung allograft dysfunction.

Chronic lung allograft dysfunction (CLAD) substantially limits long-term survival following lung transplantation. To identify potential targets for CLAD prevention, T cells from explanted CLAD lungs and lung-draining lymph nodes, as well as diseased and nondiseased controls were isolated and single-cell RNA sequencing and TCR sequencing were performed. TCR sequencing revealed a clonally expanded population of CD8+ tissue-resident memory T cells (TRMs) with high cytotoxic potential, including upregulation of KLRK1, encoding the co-receptor NKG2D.

Current perspectives on living donor selection in liver transplantation.

The careful selection of donors is crucial to achieving a successful outcome in living donor liver transplantation. The evaluation process involves obtaining a comprehensive medical history and pertinent laboratory testing, evaluating surgical anatomy using cross-sectional radiologic imaging and understanding donor motivation and psycho social considerations. This review outlines the evaluation of a potential living liver donor and discussed frequently encountered special considerations that may need to be addressed by the transplant team.

Regulatory Immune Cell-derived Exosomes: Modes of Action and Therapeutic Potential in Transplantation.

Reduced dependence on antirejection agents, improved long-term allograft survival, and induction of operational tolerance remain major unmet needs in organ transplantation due to the limitations of current immunosuppressive therapies. To address this challenge, investigators are exploring the therapeutic potential of adoptively transferred host- or donor-derived regulatory immune cells. Extracellular vesicles of endosomal origin (exosomes) secreted by these cells seem to be important contributors to their immunoregulatory properties.

Association Between Early Immunosuppression Center Variability and One-Year Outcomes After Pediatric Liver Transplant.

Background: Despite the existence of institutional protocols, liver transplant centers often have variability in early immunosuppression practices. We aimed to measure within-center variability in early immunosuppression after pediatric liver transplant (LT) and examine its association with one-year outcomes.

Methods: We analyzed pediatric LTs from 2013 to 2018 in the United Network for Organ Sharing registry, with data aggregated by center.

A multi-platform assessment of extracellular vesicles from the plasma and urine of women with preeclampsia.

Introduction: MicroRNAs (miRNAs), packaged within extracellular vesicles (EVs), have been used to interrogate the pathogenesis of preeclampsia and to identify its biomarkers. We have previously shown that miRNA species were differentially expressed in small plasma EVs from women with preeclampsia vs healthy controls. We sought to assess the use of rapid technologies for isolation of plasma and urine EVs from parturients with preeclampsia and determine differences in the expression of selected EV miRNA species.

Evolving Impact of COVID-19 on Intestinal Transplant Recipients: A Single-Center Experience.

Background: There has been significant concern about coronavirus disease 2019 (COVID-19) among transplant recipients, particularly those who are highly immunosuppressed. Several studies have analyzed the impact of COVID-19 on different solid organ transplant patients. However, few isolated case reports of COVID-19 in intestinal and multivisceral transplant (ITx and MVTx) recipients are available in the literature.

Impact of kidney allocation system 250 policy on 1-year graft loss.

A new deceased donor kidney allocation system (KAS250) was implemented in March 2021 that prioritizes recipients within a 250-nautical mile radius of the donor hospital. KAS250 was implemented to reduce geographic disparities in access to kidney transplantation. Studies have shown an increase in cold ischemia time (CIT) after KAS250 implementation but the impact on graft outcomes is unknown.

Distinct Pro-Inflammatory Species-Specific Transcriptional Changes in Human T Cells Following Pig Xenogeneic Stimulation.

Conventional T cell-directed immunosuppression is the mainstay of standard-of-care therapy to prevent graft rejection in clinical organ transplantation. However, it remains ineffective in preventing experimental and clinical organ xenograft rejection. Here, we explored the impact of allogeneic versus xenogeneic antigen stimulation on human T cell responses and gene profile.

Mechanisms governing bystander activation of T cells.

The immune system is endowed with the capacity to distinguish between self and non-self, so-called immune tolerance or "consciousness of the immune system." This type of awareness is designed to achieve host protection by eliminating cells expressing a wide range of non-self antigens including microbial-derived peptides. Such a successful immune response is associated with the secretion of a whole spectrum of soluble mediators, e.

Cardiac matrix-bound Nanovesicles provide insight into mechanisms of clinical heart disease progression to failure.

Aims: Remodeling of the extracellular matrix (ECM) is critical for effective wound healing and maintaining organ homeostasis. The ECM of soft tissues, including cardiac, contains embedded nanovesicles; or matrix-bound nanovesicles (MBV). The luminal cargo of MBV consists of lipids, microRNAs (miRNAs), and proteins that influence the function of immune and stromal cells.

Exercise Preconditioning of the Donor Liver Decreases Cold Ischemia/Reperfusion Injury in a Mouse Model.

Background: Liver transplantation stands as the primary treatment for end-stage liver disease, with demand surging in recent decades because of expanded indications. However, hepatic ischemia/reperfusion injury can lead to liver transplant failure in both deceased donor and living donor transplantation. This study explored whether preconditioning donor livers through exercise training (ExT) could mitigate cold ischemic injury posttransplantation.

TIM proteins and microRNAs: distinct impact and promising interactions on transplantation immunity.

Achieving sustained activity and tolerance in of allogeneic grafts after post-transplantation remains a substantial challenge. The response of the immune system to "non-self" MHC-antigenic peptides initiates a crucial phase, wherein blocking positive co-stimulatory signals becomes imperative to ensure graft survival and tolerance. MicroRNAs (miRNAs) inhibit mRNA translation or promote mRNA degradation by complementary binding of mRNA seed sequences, which ultimately affects protein synthesis.

Bridging the Gap: A Review of Pediatric to Adult Transition of Care in Liver Transplantation.

Background: With improvements in long-term graft function and survival, an increasing population of pediatric liver transplant (LT) recipients now require adult care. A process to successfully transition young adults to adult LT centers is supported in the literature with discussions on the rationale for health care transition (HCT), barriers to transition, stakeholder perspectives, and transfer readiness (TR). Results of outcomes studies are difficult to generalize and there remains no standard of care for HCT in LT.

Epigenetic signature of human vitamin D3 and IL-10 conditioned regulatory DCs.

During differentiation of precursor cells into their destination cell type, cell fate decisions are enforced by a broad array of epigenetic modifications, including DNA methylation, which is reflected by the transcriptome. Thus, regulatory dendritic cells (DCregs) acquire specific epigenetic programs and immunomodulatory functions during their differentiation from monocytes. To define the epigenetic signature of human DCregs generated in vitamin D3 (vitD3) and IL-10 compared to immune stimulatory DCs (sDCs), we measured levels of DNA methylation by whole genome bisulfite sequencing (WGBS).

Mitigating High-risk EBV and CMV Through Kidney Paired Donation: A Survey of Potential Donor and Recipient Candidates.

Background: High-risk cytomegalovirus (CMV) and Epstein-Barr virus (EBV) mismatches (ie, seropositive donors to seronegative recipients) among kidney transplant recipients lead to increased healthcare utilization, inferior allograft outcomes, and high mortality. We assessed the interest among prospective kidney donor and recipient candidates to participate in kidney paired donation (KPD) for averting CMV/EBV high-risk mismatches.

Methods: We surveyed 51 potential living donors and 102 kidney recipient candidates presenting for their evaluation visit at the University of Pittsburgh Medical Center between October 2022 and May 2023.

Donor-specific immune senescence as a candidate biomarker of operational tolerance following liver transplantation in adults: Results of a prospective, multicenter cohort study.

Immunosuppression can be withdrawn from selected liver transplant recipients, although robust clinical predictors of tolerance remain elusive. The Immune Tolerance Network ITN056ST study (OPTIMAL; NCT02533180) assessed clinical outcomes and mechanistic correlates of phased immunosuppression withdrawal (ISW) in nonautoimmune, nonviral adult liver transplant recipients. Enrolled subjects were ≥3 years posttransplant with minimal/absent inflammation or fibrosis on a screening liver biopsy.