Purpose of Review Over the last decade, myocarditis has been increasingly recognized as common cause of sudden cardiac death in young adults and heart failure overall. The purpose of this review is to discuss hypothesis of development of non-infectious myocarditis, to provide a description of the immunopathogenesis and the most common mechanisms of autoimmunity in myocarditis, and to provide an update on therapeutic options. Recent Findings A new entity of myocarditis is immune checkpoint inhibitor (ICI) induced myocarditis. ICIs are used in advanced cancer to "disinhibit" the immune system and make it more aggressive in fighting cancer. This novel drug class has doubled life expectancy in metastatic melanoma and significantly increased progression free survival in advanced non-small-cell lung cancer, but comes with a risk of autoimmune diseases such as myocarditis resulting from an overly aggressive immune system. Summary Myocarditis is an inflammatory disease of the heart with major public health impact. Thorough understanding of its immunopathogenesis is crucial for accurate diagnosis and effective treatment.

To evaluate whether a serial biliary dilation protocol improves outcomes and decreases total biliary drainage time for biliary strictures following pediatric liver transplantation. From 2006 to 2016, 213 orthotopic deceased and living related liver transplants were performed in 199 patients with a median patient age of 3.1 years at a single pediatric hospital. Patients with biliary strictures were managed by IR or surgically by the transplant team. Patients managed by IR were divided into two groups. The first group was managed with a standardized three‐session protocol consisting of dilation every two weeks for three dilations. The second group was managed clinically with varying number and interval of dilations as determined by a multidisciplinary team. The location of biliary stricture, duration of drainage, number of balloon dilations, balloon diameter, time interval between dilations, and success of percutaneous treatment were recorded. Thirty‐four patients developed biliary strictures. Thirty‐one patients were managed with percutaneous intervention. Three strictures could not be crossed and were converted to operative management. Ten patients were managed in the three‐session protocol, and 18 patients were managed in the clinically treated group. There was no significant difference in clinical success rates between groups, 80% and 61%, respectively. The three‐session protocol group trended toward a lower total biliary drain indwell time (median 49 days) compared with the clinically treated group (median 89 days), P = .089. Our study suggests that a three‐session dilation protocol following transplant‐related biliary stricture may decrease total biliary drainage time for some patients.

Purpose of review: To review the recent progress in xenotransplantation achieved through genetic engineering and discuss the potential of tolerance induction to overcome remaining barriers to extended xenograft survival. Recent findings: The success of life-saving allotransplantation has created a demand for organ transplantation that cannot be met by the supply of human organs. Xenotransplantation is one possible solution that would allow for a nearly unlimited supply of organs. Recent genetic engineering of swine has decreased the reactivity of preformed antibodies to some, but not all, potential human recipients. Experiments using genetically-modified swine organs have now resulted in survival of life-supporting kidneys for over a year. However, the grafts show evidence of antibody-mediated rejection on histology, suggesting additional measures will be required for further extension of graft survival. Tolerance induction through mixed chimerism or thymic transplantation across xenogeneic barriers would we well-suited for patients with a positive crossmatch to genetically-modified swine or relatively negative crossmatches to geneticallymodified swine, respectively. Summary: This review highlights the current understanding of the immunologic processes in xenotransplantation, and describes the development and application of strategies designed to overcome them from the genetic modification of the source animal to the induction of tolerance to xenografts.

We developed an approach for the expansion of Mauritian cynomolgus macaque polyspecific regulatory T cells (Tregs) through the combination of MHC‐mismatched CD40L‐engineered B cells. Expanded Tregs expressed high levels of FoxP3 and Helios, a high percentage of TSDR demethylation, and strong suppression of naïve T cell responses in vitro. This approach has the potential to be translated to clinical studies for deceased‐donor transplants.