Preoperative Sequential Portal and Hepatic Vein Embolization in Patients with Hepatobiliary Malignancy.

BACKGROUND: Preoperative portal vein embolization (PVE) induces shrinkage of the embolized lobe and compensatory regeneration in the non-embolized lobe, but does not always induce sufficient regeneration of the future remnant liver (FRL). We previously developed preoperative sequential PVE-hepatic vein embolization (HVE), and here we present our experience of treating 42 patients with sequential PVE-HVE. METHODS: During 8-year study period, preoperative PVE-HVE was performed on 42 patients with hepatobiliary malignancies. RESULTS: Primary diseases were bile duct cancers [perihilar cholangiocarcinoma (n = 33) and diffuse bile duct cancer (n = 1)], hepatocellular carcinomas (n = 4), and intrahepatic tumors [intrahepatic cholangiocarcinoma (n = 3) and gallbladder cancer liver invasion (n = 1)]. These patients demonstrated insufficient FRL regeneration following PVE, thus HVE was performed to induce further regeneration. No PVE-HVE procedure-associated complications occurred. In the bile duct cancer group, FRL volume was 33.9 ± 2.2 % before PVE, 38.4 ± 1.5 % before HVE, 43.7 ± 2.1 % at surgery, and 73.6 ± 8.3 % at 2 weeks after right hepatectomy. The degree of FRL hypertrophy was 13.3 % after PVE, 28.9 % after PHV-HVE, and 117.1 % at 2 weeks after right hepatectomy. All patients except one recovered uneventfully after surgery, and the 3-year patient survival rate was 45.1 %. In the HCC group, transarterial chemoembolization was initially performed and FRL regeneration following PVE-HVE occurred very slowly. Active FRL regeneration occurred in the liver tumor group, but rapid tumor growth was observed in 1 of 4 patients. CONCLUSION: The sequential application of HVE following PVE safely and effectively induces further FRL regeneration in non-cirrhotic livers. Further validation using larger patient population and multicenter studies is needed to reliably widen the indications.

A causal link between autoantibodies and neurological symptoms in long COVID.

Acute SARS-CoV-2 infection triggers the generation of diverse and functional autoantibodies (AABs), even after mild cases. Persistently elevated autoantibodies have been found in some individuals with long COVID (LC). Using a >21,000 human protein array, we identified diverse AAB targets in LC patients that correlated with their symptoms. Elevated AABs to proteins in the nervous system were found in LC patients with neurocognitive and neurological symptoms. Purified Immunoglobulin G (IgG) samples from these individuals reacted with human pons tissue and were cross-reactive with mouse sciatic nerves, spinal cord, and meninges. Antibody reactivity to sciatic nerves and meninges correlated with patient-reported headache and disorientation. Passive transfer of IgG from patients to mice led to increased sensitivity and pain, mirroring patient-reported symptoms. Similarly, mice injected with IgG showed loss of balance and coordination, reflecting donor-reported dizziness. Our findings suggest that targeting AABs could benefit some LC patients.

Fc-fused IL-7 provides broad antiviral effects against respiratory virus infections through IL-17A-producing pulmonary innate-like T cells.

Repeated pandemics caused by the influenza virus and severe acute respiratory syndrome coronavirus (SARS-CoV) have resulted in serious problems in global public health, emphasizing the need for broad-spectrum antiviral therapeutics against respiratory virus infections. Here, we show the protective effects of long-acting recombinant human interleukin-7 fused with hybrid Fc (rhIL-7-hyFc) against major respiratory viruses, including influenza virus, SARS-CoV-2, and respiratory syncytial virus. Administration of rhIL-7-hyFc in a therapeutic or prophylactic regimen induces substantial antiviral effects. During an influenza A virus (IAV) infection, rhIL-7-hyFc treatment increases pulmonary T cells composed of blood-derived interferon γ (IFNγ)+ conventional T cells and locally expanded IL-17A+ innate-like T cells. Single-cell RNA transcriptomics reveals that rhIL-7-hyFc upregulates antiviral genes in pulmonary T cells and induces clonal expansion of type 17 innate-like T cells. rhIL-7-hyFc-mediated disease prevention is dependent on IL-17A in both IAV- and SARS-CoV-2-infected mice. Collectively, we suggest that rhIL-7-hyFc can be used as a broadly active therapeutic for future respiratory virus pandemic.

Dietary antigens suppress the proliferation of type 2 innate lymphoid cells by restraining homeostatic IL-25 production.

Dietary antigens affect the adaptive immunity of the host by inducing regulatory T cells and IgE-producing B cells. However, their roles in innate immune compartments such as innate lymphoid cells (ILCs) and intestinal epithelial cells (IECs) are unclear. Here, using antigen-free (AF) mice, which are germ-free (GF) mice fed with amino-acid-based diet, we found dietary proteins suppress the development of GATA-3-expressing ILC2s independent of the adaptive immune cells. These cells produce more type 2 cytokines and upregulated proliferation and activation markers such as Ki-67, CD69, and CD25. With this, AF mice had increased expressions of tuft cell-specific transcripts such as Il25, Il33, Dclk1, Trpm5, and Pou2f3 in IECs. Accordingly, expanded ILC2s upregulated IL-17RB, a receptor of IL-25, and their proliferation was blocked by IL-25 neutralizing or IL-17RB blocking antibodies. These results suggest a new dialogue between dietary antigens, IECs, and ILCs in which dietary antigens suppress ILC2 activation and proliferation by restraining homeostatic IL-25 production, potentially limiting type 2 immunity by food antigens.

Confining Gold Nanoparticles in Preformed Zeolites by Post-Synthetic Modification Enhances Stability and Catalytic Reactivity and Selectivity.

Confining Au nanoparticles (NPs) in a restricted space (e.g., zeolite micropores) is a promising way of overcoming their inherent thermal instability and susceptibility to aggregation, which limit catalytic applications. However, such approaches involve complex, multistep encapsulation processes. Here, we describe a successful strategy and its guiding principles for confining small (<2 nm) and monodisperse Au NPs within commercially available beta and MFI zeolites, which can oxidize CO at 40 °C and show size-selective catalysis. This protocol involves post-synthetic modification of the zeolite internal surface with thiol groups, which confines AuCl x species inside microporous frameworks during the activation process whereby Au precursors are converted into Au nanoparticles. The resulting beta and MFI zeolites contain uniformly dispersed Au NPs throughout the void space, indicating that the intrinsic stability of the framework promotes resistance to sintering. By contrast, in situ scanning transmission electron microscopy (STEM) studies evidenced that Au precursors in bare zeolites migrate from the matrix to the external surface during activation, thereby forming large and poorly dispersed agglomerates. Furthermore, the resistance of confined Au NPs against sintering is likely relevant to the intrinsic stability of the framework, supported by extended X-ray absorption fine structure (EXAFS), H2 chemisorption, and CO Fourier transform infrared (FT-IR) studies. The Au NPs supported on commercial MFI maintain their uniform dispersity to a large extent after treatment at 700 °C that sinters Au clusters on mesoporous silicas or beta zeolites. Low-temperature CO oxidation and size-selective reactions highlight that most gold NPs are present inside the zeolite matrix with a diameter smaller than 2 nm. These findings illustrate how confinement favors small, uniquely stable, and monodisperse NPs, even for metals such as Au susceptible to cluster growth under conditions often required for catalytic use. Moreover, this strategy may be readily adapted to other zeolite frameworks that can be functionalized by thiol groups.

Homeostatic serum IgE is secreted by plasma cells in the thymus and enhances mast cell survival.

Increased serum levels of immunoglobulin E (IgE) is a risk factor for various diseases, including allergy and anaphylaxis. However, the source and ontogeny of B cells producing IgE under steady state conditions are not well defined. Here, we show plasma cells that develop in the thymus and potently secrete IgE and other immunoglobulins, including IgM, IgA, and IgG. The development of these IgE-secreting plasma cells are induced by IL-4 produced by invariant Natural Killer T cells, independent of CD1d-mediated interaction. Single-cell transcriptomics suggest the developmental landscape of thymic B cells, and the thymus supports development of transitional, mature, and memory B cells in addition to plasma cells. Furthermore, thymic plasma cells produce polyclonal antibodies without somatic hypermutation, indicating they develop via the extra-follicular pathway. Physiologically, thymic-derived IgEs increase the number of mast cells in the gut and skin, which correlates with the severity of anaphylaxis. Collectively, we define the ontogeny of thymic plasma cells and show that steady state thymus-derived IgEs regulate mast cell homeostasis, opening up new avenues for studying the genetic causes of allergic disorders.

Commensal Microbiome Expands Tγδ17 Cells in the Lung and Promotes Particulate Matter-Induced Acute Neutrophilia.

Particulate matter (PM) induces neutrophilic inflammation and deteriorates the prognosis of diseases such as cardiovascular diseases, cancers, and infections, including COVID-19. Here, we addressed the role of γδ T cells and intestinal microbiome in PM-induced acute neutrophilia. γδ T cells are a heterogeneous population composed of Tγδ1, Tγδ2, Tγδ17, and naïve γδ T cells (TγδN) and commensal bacteria promote local expansion of Tγδ17 cells, particularly in the lung and gut without affecting their Vγ repertoire. Tγδ17 cells are more tissue resident than Tγδ1 cells, while TγδN cells are circulating cells. IL-1R expression in Tγδ17 cells is highest in the lung and they outnumber all the other type 17 cells such as Th17, ILC3, NKT17, and MAIT17 cells. Upon PM exposure, IL-1ß-secreting neutrophils and IL-17-producing Tγδ17 cells attract each other around the airways. Accordingly, PM-induced neutrophilia was significantly relieved in γδ T- or IL-17-deficient and germ-free mice. Collectively, these findings show that the commensal microbiome promotes PM-induced neutrophilia in the lung via Tγδ17 cells.

Post-Synthesis Functionalization Enables Fine-Tuning the Molecular-Sieving Properties of Zeolites for Light Olefin/Paraffin Separations.

Zeolite molecular sieves are widely used in gas separation and shape-selective catalysis, but these applications often require discriminating differences as little as 0.1 Å. Molecular sieving with such size selectivity demands zeolites with highly tunable pore diameters and adsorption properties, which are technically challenging to prepare. Nevertheless, it is shown that a wide range of organic functional groups can be covalently functionalized onto the interior pore walls of the zeolites, MOR, LTL, FAU, and MFI, to systematically "tune" their effective pore diameters with respect to the size of organic groups. For organic functionalization, small and aggressive organic electrophiles are used (e.g., organo-halide and -diazonium) as grafting agents, which are accessible to the intracrystalline void space, forming a C-Ozeolite bond in a reaction with a bridging oxygen as proved by multiple analysis data. It is demonstrated that the post-functionalization can be used to tailor the molecular sieving action of a parent zeolite to give size-selective adsorbents for light olefin/paraffin separations. 4-Methoxybenzene-functionalized MOR separates ethylene from ethane with an ideal-adsorbed-solution-theory selectivity of ≈5873, whereas toluene-grafted MOR completely separates propylene/propane mixtures. Therefore, tailoring the molecular-sieving properties of zeolites by organic functionalization broadens their applications to challenging separations.

Over 500 Liver Transplants Including More Than 400 Living-Donor Liver Transplants in 2019 at Asan Medical Center.

BACKGROUND: More than 400 liver transplants were performed at Asan Medical Center (AMC) in 2011, and over 500 liver transplants including 420 living-donor liver transplants (LDLTs) were performed in 2019. Herein, we report the methodology of these procedures. METHODS: Since the first adult LDLTs at AMC using the left and right lobes were successfully performed, various innovative techniques and approaches have been developed: modified right lobe, dual graft, donor exchange for ABO incompatibility, expansion of indications and no-touch techniques for hepatocellular carcinoma, intraoperative cine-portogram and additional intervention for large collaterals, management of portal vein thrombosis (PVT) and stenosis, salvage LDLT after major hepatectomy, and timely LDLT for patients with acute-on-chronic liver failure. RESULTS: Four hundred twenty LDLTs in 403 adult and 17 pediatric patients and 85 deceased-donor liver transplants in 74 adult and 11 pediatric patients were performed. The number of deceased-donor liver transplants remained constant since 2011, but the number of LDLTs increased steadily. One hundred thirty patients (25.7%) required urgent liver transplantations and 24 patients with acute-on-chronic liver failure underwent LDLT. PVT including grade 1,2,3, and 4 was reported in 91 patients (18.0%), and Yerdel's grade 2, 3, and 4 PVT was reported in 47 patients (51.6%); all patients with PVT were successfully treated. Adult LDLTs for hepatocellular carcinoma and ABO incompatibility accounted for 52.6% and 24.3% of the cases, respectively. In-hospital mortality in 2019 was 2.97%. CONCLUSION: Continual efforts to overcome challenging problems in LDLT with various innovations and dedication of the team members during the perioperative period to improve patient outcomes were crucial in increasing the number of liver transplantations at Asan Medical Center.

Dysbiotic oral microbiota and infected salivary glands in Sjögren's syndrome.

Key events in the pathogenesis of SjÓ§gren syndrome (SS) include the change of salivary gland epithelial cells into antigen-presenting cell-like phenotypes and focal lymphocytic sialadenitis (FLS). However, what triggers these features in SS is unknown. Dysbiosis of the gut and oral microbiomes is a potential environmental factor in SS, but its connection to the etiopathogenesis of SS remains unclear. This study aimed to characterize the oral microbiota in SS and to investigate its potential role in the pathogenesis of SS. Oral bacterial communities were collected by whole mouthwash from control subjects (14 without oral dryness and 11 with dryness) and primary SS patients (8 without oral dryness and 17 with dryness) and were analyzed by pyrosequencing. The SS oral microbiota was characterized by an increased bacterial load and Shannon diversity. Through comparisons of control and SS in combined samples and then separately in non-dry and dry conditions, SS-associated taxa independent of dryness were identified. Three SS-associated species and 2 control species were selected and used to challenge human submandibular gland tumor (HSG) cells. Among the selected SS-associated bacterial species, Prevotella melaninogenica uniquely upregulated the expression of MHC molecules, CD80, and IFNλ in HSG cells. Concomitantly, P. melaninogenica efficiently invaded HSG cells. Sections of labial salivary gland (LSG) biopsies from 8 non-SS subjects and 15 SS patients were subjected to in situ hybridization using universal and P. melaninogenica-specific probes. Ductal cells and the areas of infiltration were heavily infected with bacteria in the LSGs with FLS. Collectively, dysbiotic oral microbiota may initiate the deregulation of SGECs and the IFN signature through bacterial invasion into ductal cells. These findings may provide new insights into the etiopathogenesis of SS.

Single-cell RNA sequencing identifies shared differentiation paths of mouse thymic innate T cells.

Invariant natural killer T (iNKT), mucosal-associated invariant T (MAIT), and γδ T cells are innate T cells that acquire memory phenotype in the thymus and share similar biological characteristics. However, how their effector differentiation is developmentally regulated is still unclear. Here, we identify analogous effector subsets of these three innate T cell types in the thymus that share transcriptional profiles. Using single-cell RNA sequencing, we show that iNKT, MAIT and γδ T cells mature via shared, branched differentiation rather than linear maturation or TCR-mediated instruction. Simultaneous TCR clonotyping analysis reveals that thymic maturation of all three types is accompanied by clonal selection and expansion. Analyses of mice deficient of TBET, GATA3 or RORγt and additional in vivo experiments corroborate the predicted differentiation paths, while human innate T cells from liver samples display similar features. Collectively, our data indicate that innate T cells share effector differentiation processes in the thymus.

Severe Intraperitoneal Hemorrhage from Pseudoaneurysm after a Large-volume Paracentesis, Successfully Treated with Microcoil Embolization.

Large-volume paracentesis-induced intraperitoneal hemorrhage due to pseudoaneurysm formation is rarely reported. Here, we present a 56-year-old man with alcoholic liver cirrhosis admitted for massive ascites. Large-volume paracentesis was performed. Three days later, he became pale and complained of dyspnea and abdominal distention with hypotension. Percutaneous iliac angiography revealed contrast media leakage from a branch of the left circumflex iliac artery with pseudoaneurysm. He was successfully treated with microcoil embolization. Several days later, ascitic fluid increased and large-volume paracentesis was performed again. Two days later, his hemoglobin level suddenly decreased. An abdominal computed tomography scan showed new active bleeding at the left lower lateral peritoneal cavity, just anterior to the metalic coils. Percutaneous iliac angiography revealed contrast media extravasation from a branch of the left inferior epigastric artery with formation of collateral vessel. Percutaneous embolization was successfully performed again. After coil embolization, there were no further bleeding episodes.

Lineage Differentiation Program of Invariant Natural Killer T Cells.

Invariant natural killer T (iNKT) cells are innate T cells restricted by CD1d molecules. They are positively selected in the thymic cortex and migrate to the medullary area, in which they differentiate into 3 different lineages. Promyelocytic leukemia zinc finger (PLZF) modulates this process, and PLZFhigh, PLZFintermediate, and PLZFlow iNKT cells are designated as NKT2, NKT17, and NKT1 cells, respectively. Analogous to conventional helper CD4 T cells, each subset expresses distinct combinations of transcription factors and produces different cytokines. In lymphoid organs, iNKT subsets have unique localizations, which determine their cytokine responses upon antigenic challenge. The lineage differentiation programs of iNKT cells are differentially regulated in various mice strains in a cell-intrinsic manner, and BALB/c mice contain a high frequency of NKT2 cells. In the thymic medulla, steady state IL-4 from NKT2 cells directly conditions CD8 T cells to become memory-like cells expressing Eomesodermin, which function as premade memory effectors. The genetic signature of iNKT cells is more similar to that of γδ T cells and innate lymphoid cells (ILCs) than of conventional helper T cells, suggesting that ILCs and innate T cells share common developmental programs.

Cluster Hepaticojejunostomy Is a Useful Technique Enabling Secure Reconstruction of Severely Damaged Hilar Bile Ducts.

Secure reconstruction of multiple hepatic ducts severely damaged by tumor invasion or iatrogenic injury is very difficult. If percutaneous or endoscopic biliary stenting fails, one or more percutaneous transhepatic biliary drainage (PTBD) tubes must be maintained in place for the rest of the patient's life. To cope with such difficult situations, we present a surgical technique termed cluster hepaticojejunostomy (HJ), which can be coupled with palliative bile duct resection. The cluster HJ technique consisted of applying multiple internal biliary stents and a single wide porto-enterostomy to surrounding connective tissues. We present a preliminary study with six patients. Five perihilar cholangiocarcinoma patients undergoing palliative bile duct resection received this procedure. Follow-up PTBD tubogram and hepatobiliary scintigraphy were performed at 1-2 weeks after surgery, after which the PTBD tubes were removed. No patient showed surgical complications, and the 6-month patency rate of clustered HJ was 80%. Another patient with laparoscopic cholecystectomy-associated major bile duct injury showed no biliary complications in the 5-year period following this procedure. Based on the results of this study, the cluster HJ technique may be a useful surgical method enabling the secure reconstruction of severely damaged hilar bile ducts.

Spontaneous rupture of intrahepatic bile duct following portal vein embolization in a patient with perihilar cholangiocarcinoma: a case of successful curative resection.

We herein present a case of spontaneous rupture of intrahepatic bile duct in a patient with perihilar cholangiocarcinoma, which were successfully treated by curative resection. A 60-year-old male patient with perihilar cholangiocarcinoma was decompressed with single percutaneous transhepatic biliary drainage. Two days after right portal vein embolization, the patient suffered from paralytic ileus with marked abdominal distension. Imaging study revealed that marked fluid collection around the liver and whole abdomen, suggesting intrahepatic bile duct rupture. With abdominal drainage and biliary decompression for 2 weeks, the biliary rupture was controlled. To enhance the safety of right hepatectomy, additional right hepatic vein embolization was performed. The patient underwent routine surgical procedures for right hepatectomy, caudate lobectomy and bile duct resection, and recovered uneventfully and discharged 18 days after surgery. This is the first report of a case of spontaneous rupture of intrahepatic bile duct in a patient with perihilar cholangiocarcinoma.