Covalent immobilization of human serum albumin on cellulose acetate membrane for scavenging amyloid beta - A stepping extracorporeal strategy for ameliorating Alzheimer's disease.

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by interrupted neurocognitive functions and impaired mental development presumably caused by the accumulation of amyloid beta (Aß) in the form of plaques. Targeting Aß has been considered a promising approach for treating AD. In the current study, human serum albumin (HSA), a natural Aß binder, is covalently immobilized onto the surface of a cellulose acetate (CA) membrane to devise an extracorporeal Aß sequester. The immobilization of HSA at 3.06 ± 0.22 µg/mm2 of the CA membrane was found to be active functionally, as evidenced by the esterase-like activity converting p-nitrophenyl acetate into p-nitrophenol. The green fluorescent protein-Aß (GFP-Aß) fusion protein, recombinantly produced as a model ligand, exhibited characteristics of native Aß. These features include the propensity to form aggregates or fibrils and an affinity for HSA with a dissociation constant (KD) of 0.91 µM. The HSA on the CA membrane showed concentration-dependent sequestration of GFP-Aß in the 1-10-µM range. Moreover, it had a greater binding capacity than HSA immobilized on a commercial amine-binding plate. Results suggest that the covalent immobilization of HSA on the CA surface can be used as a potential platform for sequestering Aß to alleviate AD.

Development and evaluation of bioinspired pH-responsive sericin-chitosan-based hydrogel for controlled colonic delivery of PETase: Harnessing PETase-triggered degradation of microplastics.

The gravity of threats posed by microplastic pollution to the environment cannot be overestimated. Being ubiquitous in the living environment, microplastics reach humans through the food chain causing various hazardous effects. Microplastics can be effectively degraded by PETase enzymes. The current study reports, for the first time, a hydrogel-encapsulated, bioinspired colonic delivery of PETase. A free radical polymerization-assisted hydrogel system was synthesized from sericin, chitosan, and acrylic acid using N,N'-methylenebisacrylamide as a crosslinker and ammonium persulfate as an initiator. The hydrogel was characterized with FTIR, PXRD, SEM, and thermal analysis to confirm the development of a stabilized hydrogel system. The hydrogel showed 61 % encapsulation efficiency, maximum swelling, and cumulative PETase release (96 %) at pH 7.4. The mechanism of PETase release exhibited the Higuchi pattern of release with an anomalous transport mechanism. SDS-PAGE analysis confirmed the preservation of the post-release structural integrity of PETase. The released PETase exhibited concentration- and time-dependent degradation of polyethylene terephthalate in vitro. The developed hydrogel system exhibited the intended features of a stimulus-sensitive carrier system that can be efficiently used for the colonic delivery of PETase.

YH29407 with anti-PD-1 ameliorates anti-tumor effects via increased T cell functionality and antigen presenting machinery in the tumor microenvironment.

Among cancer cells, indoleamine 2, 3-dioxygenase1 (IDO1) activity has been implicated in improving the proliferation and growth of cancer cells and suppressing immune cell activity. IDO1 is also responsible for the catabolism of tryptophan to kynurenine. Depletion of tryptophan and an increase in kynurenine exert important immunosuppressive functions by activating regulatory T cells and suppressing CD8+ T and natural killer (NK) cells. In this study, we compared the anti-tumor effects of YH29407, the best-in-class IDO1 inhibitor with improved pharmacodynamics and pharmacokinetics, with first and second-generation IDO1 inhibitors (epacadostat and BMS-986205, respectively). YH29407 treatment alone and anti-PD-1 (aPD-1) combination treatment induced significant tumor suppression compared with competing drugs. In particular, combination treatment showed the best anti-tumor effects, with most tumors reduced and complete responses. Our observations suggest that improved anti-tumor effects were caused by an increase in T cell infiltration and activity after YH29407 treatment. Notably, an immune depletion assay confirmed that YH29407 is closely related to CD8+ T cells. RNA-seq results showed that treatment with YH29407 increased the expression of genes involved in T cell function and antigen presentation in tumors expressing ZAP70, LCK, NFATC2, B2M, and MYD88 genes. Our results suggest that an IDO1 inhibitor, YH29407, has enhanced PK/PD compared to previous IDO1 inhibitors by causing a change in the population of CD8+ T cells including infiltrating T cells into the tumor. Ultimately, YH29407 overcame the limitations of the competing drugs and displayed potential as an immunotherapy strategy in combination with aPD-1.

Mice transgenic for human CTLA4-CD28 fusion gene show proliferation and transformation of ATLL-like and AITL-like T cells.

CTLA4-CD28 gene fusion has been reported to occur in diverse types of T cell lymphoma. The fusion event is expected to convert inhibitory signals to activating signals and promote proliferation and potentially transformation of T cells. To test the function of the CTLA4-CD28 fusion gene in vivo, we generated a murine model that expresses the gene in a T cell-specific manner. The transgenic mice have shorter life spans and display inflammatory responses including lymphadenopathy and splenomegaly. T cells in turn show higher levels of activation and infiltrate various organs including the lung and skin. T cells, in particular CD4+ helper T cells, were also readily transplantable to immunocompromised mice. Transcriptomic profiling revealed that the gene expression pattern in CD4 + T cells closely resembles that of adult T cell leukemia/lymphoma (ATLL) and that of angioimmunoblastic T cell lymphoma (AITL) tissues. Consistently, we detected supernumerary FOXP3+ cells and PD-1+ cells in transgenic and transplanted mice. This is the first report demonstrating the transforming activity of the CTLA4-CD28 fusion gene in vivo, and this murine model should be useful in dissecting the molecular events downstream to this mutation.

A Novel Kinase Inhibitor AX-0085 Inhibits Interferon-γ-Mediated Induction of PD-L1 Expression and Promotes Immune Reaction to Lung Adenocarcinoma Cells.

In this study, we describe a novel kinase inhibitor AX-0085 which can suppress the induction of PD-L1 expression by Interferon-γ (IFN-γ) in lung adenocarcinoma (LUAD) cells. AX-0085 effectively blocks JAK2/STAT1 signaling initiated by IFN-γ treatment and prevents nuclear localization of STAT1. Importantly, we demonstrate that AX-0085 reverses the IFN-γ-mediated repression of T cell activation in vitro and enhances the anti-tumor activity of anti-PD-1 antibody in vivo when used in combination. Finally, transcriptomic analyses indicated that AX-0085 is highly specific in targeting the IFN-γ-pathway, thereby raising the possibility of applying this reagent in combination therapy with checkpoint inhibitor antibodies. It may be particularly relevant in cases in which PD-L1-mediated T cell exhaustion leads to immunoevasive phenotypes.

Angioimmunoblastic T-cell lymphoma-like lymphadenopathy in mice transgenic for human RHOA with p.Gly17Val mutation.

A missense mutation in RHOA encoding p.Gly17 Val has been reported to occur frequently in angioimmunoblastic T-cell lymphoma (AITL). Here, we describe a murine model which expresses the human RHOA mutant gene product in a T-cell specific manner and develops AITL-like symptoms. Most transgenic mice feature with latency one or two enlarged lymph nodes characterized by aberrant lymph node architecture, extensive lymphocytic infiltration, extrafollicular meshwork of follicular dendritic cells (FDC) and arborized endothelial venules. Importantly, we provide evidence for expansion of PD-1+ follicular helper T (Tfh) cells which are the neoplastic cells of AITL. In addition, we saw proliferation of B-cells leading to hypergammaglobulinemia and the presence of dominant T cell clonal populations. Transplantation of lymph node cells to immunocompromised mice partly recreated lymphadenopathy after a long latency and with low penetrance suggesting that cells have undergone partial transformation to a premalignant state. Transcriptomic profiling revealed that the gene expression pattern within affected lymph nodes of the mice closely resembles that of AITL patients with the identical RHOA p.Gly17 Val mutation. The murine model should, therefore, be useful in dissecting pathogenesis of AITL at the molecular level particularly for the cases with the RHOA p.Gly17Val mutation.

Effectiveness of Premedication with Pronase for Visualization of the Mucosa during Endoscopy: A Randomized, Controlled Trial.

BACKGROUND/AIMS: Gastric mucus should be removed before endoscopic examination to increase visibility. In this study, the effectiveness of premedication with pronase for improving visibility during endoscopy was investigated. METHODS: From April 2010 to February 2011, 400 outpatients were randomly assigned to receive endoscopy with one of four premedications as follows: dimethylpolysiloxane (DMPS), pronase and sodium bicarbonate with 10 minutes premedication time (group A, n=100), DMPS and sodium bicarbonate with 10 minutes premedication time (group B, n=100), DMPS, pronase and sodium bicarbonate with 20 minutes premedication time (group C, n=100), and DMPS and sodium bicarbonate with 20 minute premedication time (group D, n=100). One endoscopist, who was unaware of the premedication types, calculated the visibility scores (range, 1 to 3) of the antrum, lower gastric body, upper gastric body and fundus. The sum of the scores from the four locations was defined as the total visibility score. RESULTS: Group C showed significantly lower scores than other groups (p=0.002). Group C also had the lowest frequency of flushing, which was significantly lower than that of group D. Groups C and D had significantly shorter durations of examination than groups A and B. CONCLUSIONS: Using pronase 20 minutes before endoscopy significantly improved endoscopic visualization and decreased the frequency of water flushing.

[Comparison of treatments in patients with inoperable stage IV advanced esophageal cancer].

BACKGROUND/AIMS: The aim of this study was to compare palliative treatments such as chemotherapy, chemoradiotherapy or radiotherapy with best supportive care in patients with inoperable advanced esophageal cancer. METHODS: A total of 67 patients with inoperable advanced esophageal cancer visiting Kosin University Gospel Hospital between January 2000 and July 2010 were included in a retrospective analysis. Patients were categorized as having palliative treatment or best supportive care to compare their prognosis. RESULTS: The median survival was 6.4 months in 67 patients. There was significant difference in median survival between the palliative and best supportive treatment (9.8 months vs. 4.5 months, p=0.01). The patients who underwent palliative treatment had superior 1-year and 3-year overall survival rate than those with best supportive treatment (27%, 10% vs. 5%, 5%, respectively). The 1-year and 3-year overall survival rate of palliative treatment was 18% (1-year overall survival rate) in chemotherapy, 33% (1-year overall survival rate) in radiotherapy, 45% and 9% in concurrent chemoradiotherapy, and 20% and 20% in sequential chemoradiotherapy, respectively. CONCLUSIONS: These results may suggest that palliative treatments are more effective than best supportive care. Further prospective studies are still needed to elucidate beneficial effect of palliative treatments on inoperable advanced esophageal cancer.

Are Food Constituents Relevant to the Irritable Bowel Syndrome in Young Adults? - A Rome III Based Prevalence Study of the Korean Medical Students.

BACKGROUND/AIMS: Irritable bowel syndrome (IBS) is prevalent in general population. This study investigates the prevalence of IBS in medical college students in Korea as well as the influence of dietary habits and nutritional intake on IBS. METHODS: This study is a cross-sectional study of 319 students (239 males and 80 females, age 22.3 ± 2.5 years) from the 6 grade levels of the Medical College in Korea. All students filled out a self-reported questionnaire for ROME III criteria. They also completed a questionnaire to validate dietary habits and food frequency in Korean. RESULTS: The overall prevalence of IBS was 29.2% without correlation to age, body mass index and grade level in Medical School. However, the prevalence was significantly higher in females than males (33/80 vs 60/239, P = 0.007). There were no significant differences between the IBS-group and the non-IBS group in aspect of nutrition. Not only the diet habits, but also the daily nutritional intake, and even the breakdown into the 12 micronutrients, yielded no significant differences between the 2 groups. CONCLUSIONS: Twenty-nine percent of the medical college students have IBS with a greater prevalence in females. The dietary habits and nutritional intake of the students might not be associated with IBS.