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Once considered a tissue culture-specific phenomenon, cellular senescence has now been linked to various biological processes with both beneficial and detrimental roles in humans, rodents and other species. Much of our understanding of senescent cell biology still originates from tissue culture studies, where each cell in the culture is driven to an irreversible cell cycle arrest. By contrast, in tissues, these cells are relatively rare and difficult to characterize, and it is now established that fully differentiated, postmitotic cells can also acquire a senescence phenotype. The SenNet Biomarkers Working Group was formed to provide recommendations for the use of cellular senescence markers to identify and characterize senescent cells in tissues. Here, we provide recommendations for detecting senescent cells in different tissues based on a comprehensive analysis of existing literature reporting senescence markers in 14 tissues in mice and humans. We discuss some of the recent advances in detecting and characterizing cellular senescence, including molecular senescence signatures and morphological features, and the use of circulating markers. We aim for this work to be a valuable resource for both seasoned investigators in senescence-related studies and newcomers to the field., Competing Interests: Competing interests: The authors declare the following competing interests: J.C. is a founder and shareholder of Unity Biotechnology, which develops senolytic drugs. M.J.S., C.M.C. and Mayo Clinic have intellectual property related to this research. Research in the M.J.S. and D.J.B. laboratory is reviewed by the Mayo Clinic Conflict of Interest Review Board and conducted in compliance with Mayo Clinic Conflict of Interest policies. D.J.B. has a potential financial interest related to this research; he is a co-inventor on patents held by Mayo Clinic and patent applications licensed to or filed by Unity Biotechnology and a Unity Biotechnology shareholder. N. Slavov is a founding director and CEO of Parallel Squared Technology Institute, which is a non-profit research institute., (© 2024. Springer Nature Limited.)

There has been growing research interest in developing methodology to evaluate the health care providers' performance with respect to a patient outcome. Random and fixed effects models are traditionally used for such a purpose. We propose a new method, using a fusion penalty to cluster health care providers based on quasi-likelihood. Without any priori knowledge of grouping information, our method provides a desirable data-driven approach for automatically clustering health care providers into different groups based on their performance. Further, the quasi-likelihood is more flexible and robust than the regular likelihood in that no distributional assumption is needed. An efficient alternating direction method of multipliers algorithm is developed to implement the proposed method. We show that the proposed method enjoys the oracle properties; namely, it performs as well as if the true group structure were known in advance. The consistency and asymptotic normality of the estimators are established. Simulation studies and analysis of the national kidney transplant registry data demonstrate the utility and validity of our method., (© 2024 Wiley‐VCH GmbH.)

Multiple Myeloma (MM) remains incurable despite advances in treatment options. Although tumor subtypes and specific DNA abnormalities are linked to worse prognosis, the impact of immune dysfunction on disease emergence and/or treatment sensitivity remains unclear. We established a harmonized consortium to generate an Immune Atlas of MM aimed at informing disease etiology, risk stratification, and potential therapeutic strategies. We generated a transcriptome profile of 1,149,344 single cells from the bone marrow of 263 newly diagnosed patients enrolled in the CoMMpass study and characterized immune and hematopoietic cell populations. Associating cell abundances and gene expression with disease progression revealed the presence of a proinflammatory immune senescence-associated secretory phenotype in rapidly progressing patients. Furthermore, signaling analyses suggested active intercellular communication involving APRIL-BCMA, potentially promoting tumor growth and survival. Finally, we demonstrate that integrating immune cell levels with genetic information can significantly improve patient stratification.

In this article, we present a flexible model for microbiome count data. We consider a quasi-likelihood framework, in which we do not make any assumptions on the distribution of the microbiome count except that its variance is an unknown but smooth function of the mean. By comparing our model to the negative binomial generalized linear model (GLM) and Poisson GLM in simulation studies, we show that our flexible quasi-likelihood method yields valid inferential results. Using a real microbiome study, we demonstrate the utility of our method by examining the relationship between adenomas and microbiota. We also provide an R package "fql" for the application of our method., (© 2023 John Wiley & Sons Ltd.)

Chromatin accessibility is essential in regulating gene expression and cellular identity, and alterations in accessibility have been implicated in driving cancer initiation, progression and metastasis 1-4 . Although the genetic contributions to oncogenic transitions have been investigated, epigenetic drivers remain less understood. Here we constructed a pan-cancer epigenetic and transcriptomic atlas using single-nucleus chromatin accessibility data (using single-nucleus assay for transposase-accessible chromatin) from 225 samples and matched single-cell or single-nucleus RNA-sequencing expression data from 206 samples. With over 1 million cells from each platform analysed through the enrichment of accessible chromatin regions, transcription factor motifs and regulons, we identified epigenetic drivers associated with cancer transitions. Some epigenetic drivers appeared in multiple cancers (for example, regulatory regions of ABCC1 and VEGFA; GATA6 and FOX-family motifs), whereas others were cancer specific (for example, regulatory regions of FGF19, ASAP2 and EN1, and the PBX3 motif). Among epigenetically altered pathways, TP53, hypoxia and TNF signalling were linked to cancer initiation, whereas oestrogen response, epithelial-mesenchymal transition and apical junction were tied to metastatic transition. Furthermore, we revealed a marked correlation between enhancer accessibility and gene expression and uncovered cooperation between epigenetic and genetic drivers. This atlas provides a foundation for further investigation of epigenetic dynamics in cancer transitions., (© 2023. The Author(s).)

DNA methylation plays a critical role in establishing and maintaining cellular identity. However, it is frequently dysregulated during tumor development and is closely intertwined with other genetic alterations. Here, we leveraged multi-omic profiling of 687 tumors and matched non-involved adjacent tissues from the kidney, brain, pancreas, lung, head and neck, and endometrium to identify aberrant methylation associated with RNA and protein abundance changes and build a Pan-Cancer catalog. We uncovered lineage-specific epigenetic drivers including hypomethylated FGFR2 in endometrial cancer. We showed that hypermethylated STAT5A is associated with pervasive regulon downregulation and immune cell depletion, suggesting that epigenetic regulation of STAT5A expression constitutes a molecular switch for immunosuppression in squamous tumors. We further demonstrated that methylation subtype-enrichment information can explain cell-of-origin, intra-tumor heterogeneity, and tumor phenotypes. Overall, we identified cis-acting DNA methylation events that drive transcriptional and translational changes, shedding light on the tumor's epigenetic landscape and the role of its cell-of-origin., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.)

DNA replication stress (RS) is frequently induced by oncogene activation and is believed to promote tumorigenesis. However, clinical evidence for the role of oncogene-induced RS in tumorigenesis remains scarce, and the mechanisms by which RS promotes cancer development remain incompletely understood. By performing a series of bioinformatic analyses on the oncogene E2F1, other RS-inducing factors, and replication fork processing factors in TCGA cancer database using previously established tools, we show that hyperactivity of E2F1 likely promotes the expression of several of these factors in virtually all types of cancer to induce RS and cytosolic self-DNA production. In addition, the expression of these factors positively correlates with that of ATR and Chk1 that govern the cellular response to RS, the tumor mutational load, and tumor infiltration of immune-suppressive CD4 + Th2 cells and myeloid-derived suppressor cells (MDSCs). Consistently, high expression of these factors is associated with poor patient survival. Our study provides new insights into the role of E2F1-induced RS in tumorigenesis and suggests therapeutic approaches for E2F1-overexpressing cancers by targeting genomic instability, cytosolic self-DNA and the tumor immune microenvironment., Competing Interests: Declaration of Competing Interest The authors declare no conflicts of interest., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Post-translational modifications (PTMs) play key roles in regulating cell signaling and physiology in both normal and cancer cells. Advances in mass spectrometry enable high-throughput, accurate, and sensitive measurement of PTM levels to better understand their role, prevalence, and crosstalk. Here, we analyze the largest collection of proteogenomics data from 1,110 patients with PTM profiles across 11 cancer types (10 from the National Cancer Institute's Clinical Proteomic Tumor Analysis Consortium [CPTAC]). Our study reveals pan-cancer patterns of changes in protein acetylation and phosphorylation involved in hallmark cancer processes. These patterns revealed subsets of tumors, from different cancer types, including those with dysregulated DNA repair driven by phosphorylation, altered metabolic regulation associated with immune response driven by acetylation, affected kinase specificity by crosstalk between acetylation and phosphorylation, and modified histone regulation. Overall, this resource highlights the rich biology governed by PTMs and exposes potential new therapeutic avenues., Competing Interests: Declaration of interests Y.G. is a consultant for Oriel Research Therapeutics. T.M.Y. is a co-founder, stockholder, and on the board of directors of DESTROKE, Inc., an early-stage start-up developing mobile technology for automated clinical stroke detection. J.L.J. has received consulting fees from Scorpion Therapeutics and Volastra Therapeutics. Y.E.M. is a consultant for ForseeGenomics and is also an inventor on patent applications filed by the Broad Institute related to MSMuTect, MSMutSig, and MSIDetect. N.J.H. is a consultant for MorphoSys. F.A. is an inventor on a patent application related to SignatureAnalyzer-GPU and has been an employee of Illumina, Inc., since 8 November 2021. L.C.C. is a founder and member of the board of directors of Agios Pharmaceuticals and is a founder of Petra Pharmaceuticals. L.C.C. is an inventor on patents (pending) for Combination Therapy for PI3K-associated Disease or Disorder, and The Identification of Therapeutic Interventions to Improve Response to PI3K Inhibitors for Cancer Treatment. L.C.C. is a co-founder and shareholder in Faeth Therapeutics. G.G. receives research funds from IBM, Pharmacyclics, and Ultima Genomics, and is also an inventor on patent applications filed by the Broad Institute related to MSMuTect, MSMutSig, POLYSOLVER, SignatureAnalyzer-GPU, MSIDetect, and MinimuMM-Seq. He is also a founder, consultant, and privately held equity in Scorpion Therapeutics., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Cancer driver events refer to key genetic aberrations that drive oncogenesis; however, their exact molecular mechanisms remain insufficiently understood. Here, our multi-omics pan-cancer analysis uncovers insights into the impacts of cancer drivers by identifying their significant cis-effects and distal trans-effects quantified at the RNA, protein, and phosphoprotein levels. Salient observations include the association of point mutations and copy-number alterations with the rewiring of protein interaction networks, and notably, most cancer genes converge toward similar molecular states denoted by sequence-based kinase activity profiles. A correlation between predicted neoantigen burden and measured T cell infiltration suggests potential vulnerabilities for immunotherapies. Patterns of cancer hallmarks vary by polygenic protein abundance ranging from uniform to heterogeneous. Overall, our work demonstrates the value of comprehensive proteogenomics in understanding the functional states of oncogenic drivers and their links to cancer development, surpassing the limitations of studying individual cancer types., Competing Interests: Declaration of interests Y.G. is a consultant for Oriel Research Therapeutics. T.M.Y. is a co-founder, stockholder, and member of the board of directors of DESTROKE, Inc., an early-stage start-up developing mobile technology for automated clinical stroke detection. J.L.J. has received consulting fees from Scorpion Therapeutics and Volastra Therapeutics. F.A. is an inventor on a patent application related to SignatureAnalyzer-GPU and has been an employee of Illumina, Inc., since 8 November 2021. L.C.C. is a founder and member of the board of directors of Agios Pharmaceuticals and is a founder of Petra Pharmaceuticals. L.C.C. is an inventor on patents (pending) for Combination Therapy for PI3K-associated Disease or Disorder, and The Identification of Therapeutic Interventions to Improve Response to PI3K Inhibitors for Cancer Treatment. L.C.C. is a co-founder and shareholder in Faeth Therapeutics. G.G. receives research funds from IBM, Pharmacyclics, and Ultima Genomics and is also an inventor on patent applications filed by the Broad Institute related to MSMuTect, MSMutSig, POLYSOLVER, SignatureAnalyzer-GPU, MSIDetect, and MinimuMM-Seq. G.G. is also a founder, consultant, and privately held equity in Scorpion Therapeutics., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Objective: To identify prescription medications associated with a lower risk of three neurodegenerative diseases: Parkinson disease, Alzheimer disease, and amyotrophic lateral sclerosis., Methods: We conducted a population-based, case-control study of U.S. Medicare beneficiaries in 2009 (42,885 incident neurodegenerative disease cases, 334,387 randomly selected controls). Using medication data from 2006-2007, we categorized all filled medications according to their biological targets and mechanisms of action on those targets. We used multinomial logistic regression models, while accounting for demographics, indicators of smoking, and health care utilization, to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for 141 target-action pairs and each neurodegenerative disease. For target-action pairs inversely associated with all three diseases, we attempted replication in a cohort study that included an active comparator group. We constructed the cohort by following controls forward for incident neurodegenerative disease from the beginning of 2010 until death or end of 2014, i.e., up to five years after the two-year exposure lag. We used Cox proportional hazards regression while accounting for the same covariates., Results: The most consistent inverse association across both studies and all three neurodegenerative diseases was for xanthine dehydrogenase/oxidase blockers, represented by the gout medication, allopurinol. Allopurinol was associated with a 13-34% lower risk for each neurodegenerative disease group in multinomial regression, and a mean reduction of 23% overall, as compared to individuals who did not use allopurinol. In the replication cohort we observed a significant 23% reduction for neurodegenerative disease in the fifth year of follow-up, when comparing allopurinol users to non-users, and more marked associations with an active comparator group. We observed parallel associations for a related target-action pair unique to carvedilol., Discussion/conclusion: Xanthine dehydrogenase/oxidase blockade might reduce risk of neurodegenerative disease. However, further research will be necessary to confirm that the associations related to this pathway are causal or to examine whether this mechanism slows progression., Competing Interests: In addition to the funding sources that supported the present work, Dr. Searles Nielsen, Dr. Racette and Dr. Camacho-Soto received additional funding from NIH – NIEHS (R01ES029524, R01ES026891, R01ES026891-S1, R01ES025991, and/or R01ES025991-S1) and The Michael J. Fox Foundation for Parkinson’s Research (Grants 000939 and/or 020718). Dr. Racette has received personal compensation for lectures from the University of Michigan, expert testimony unrelated to the topic of this manuscript, peer review from the Parkinson Study Group, and service on the National Advisory Environmental Health Sciences Council for NIEHS. This does not alter our adherence to PLOS ONE policies on sharing data and materials., (Copyright: © 2023 Song et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Objective: The objective of this study was to use a novel combined pharmacoepidemiologic and amyotrophic lateral sclerosis (ALS) mouse model approach to identify potential motor neuron protective medications., Methods: We constructed a large, population-based case-control study to investigate motor neuron disease (MND) among US Medicare beneficiaries aged 66 to 90 in 2009. We included 1,128 incident MND cases and 56,400 age, sex, race, and ethnicity matched controls. We calculated MND relative risk for >1,000 active ingredients represented in Part D (pharmacy) claims in 2006 to 2007 (>1 year before diagnosis/reference). We then applied a comprehensive screening approach to select medications for testing in SOD1 G93A mice: sulfasalazine, telmisartan, and lovastatin. We treated mice with the human dose equivalent of the medication or vehicle via subcutaneous osmotic pump before onset of weakness. We then assessed weight, gait, and survival. In additional mice, we conducted histological studies., Results: We observed previously established medical associations for MND and an inverse dose-response association between lovastatin and MND, with 28% reduced risk at 40 mg/day. In SOD1 G93A mouse studies, sulfasalazine and telmisartan conferred no benefit, whereas lovastatin treatment delayed onset and prolonged survival. Lovastatin treated mice also had less microgliosis, misfolded SOD1, and spinal motor neuron loss in the ventral horn., Interpretation: Lovastatin reduced the risk of ALS in humans, which was confirmed in an ALS mouse model by delayed symptom onset, prolonged survival, and preservation of motor neurons. Although further studies to understand the mechanism are required, lovastatin may represent a potential neuroprotective therapy for patients with ALS. These data demonstrate the utility of a combined pharmacoepidemiologic and mouse model approach. ANN NEUROL 2023;93:881-892., (© 2023 American Neurological Association.)

Multiple myeloma (MM) is a highly refractory hematologic cancer. Targeted immunotherapy has shown promise in MM but remains hindered by the challenge of identifying specific yet broadly representative tumor markers. We analyzed 53 bone marrow (BM) aspirates from 41 MM patients using an unbiased, high-throughput pipeline for therapeutic target discovery via single-cell transcriptomic profiling, yielding 38 MM marker genes encoding cell-surface proteins and 15 encoding intracellular proteins. Of these, 20 candidate genes were highlighted that are not yet under clinical study, 11 of which were previously uncharacterized as therapeutic targets. The findings were cross-validated using bulk RNA sequencing, flow cytometry, and proteomic mass spectrometry of MM cell lines and patient BM, demonstrating high overall concordance across data types. Independent discovery using bulk RNA sequencing reiterated top candidates, further affirming the ability of single-cell transcriptomics to accurately capture marker expression despite limitations in sample size or sequencing depth. Target dynamics and heterogeneity were further examined using both transcriptomic and immuno-imaging methods. In summary, this study presents a robust and broadly applicable strategy for identifying tumor markers to better inform the development of targeted cancer therapy., Significance: Single-cell transcriptomic profiling and multiomic cross-validation to uncover therapeutic targets identifies 38 myeloma marker genes, including 11 transcribing surface proteins with previously uncharacterized potential for targeted antitumor therapy., (©2023 The Authors; Published by the American Association for Cancer Research.)

Background: Human pluripotent stem cells (hPSCs) have started to emerge as a potential tool with application in fields of drug discovery, disease modelling and cell therapy. A variety of protocols for culturing and differentiating pluripotent stem cells into pancreatic β like cells have been published. However, small-scale dynamic suspension culture systems, which could be applied toward systematically optimizing production strategies for cell replacement therapies to accelerate the pace of their discovery and development toward the clinic, are overlooked., Methods: Human embryonic stem cell (hESC) line H9 was used to establish the novel 48-well dynamic suspension culture system. The effects of various rotational speeds and culture medium volumes on cell morphology, cell proliferation, cell viability and cell phenotype were evaluated. Effect of cell density on the pancreatic differentiation efficiency from H9 cells in 48-well plates was further investigated. In vitro the function of pancreatic β like cells was assessed by measuring glucose-stimulated insulin secretion., Main Results: A 48-well dynamic suspension culture system for hESC expansion as cell aggregates was developed. With optimized rotational speed and culture medium volume, hESCs maintained normal karyotype, viability and pluripotency. Furthermore, the system can also support the hESC aggregates subsequent differentiation into functional pancreatic β like cells after optimizing initial cell seeding density., Conclusion: A controllable 48-well suspension culture system in microplates for hESCs maintenance, expansion and pancreatic differentiation was developed, which may provide an efficient platform for high-throughput drug screening., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Bioengineering functional hepatic tissue constructs that physiologically replicate the human native liver tissue in vitro is sought for clinical research and drug discovery. However, the intricate architecture and specific biofunctionality possessed by the native liver tissue remain challenging to mimic in vitro . In the present study, a versatile strategy to fabricate lobular-like silk protein scaffolds with radially aligned lamellar sheets, interconnected channels, and a converging central cavity was designed and implemented. A proof-of-concept study to bioengineer biomimetic hepatic lobules was conducted through coculturing human hepatocytes and primary endothelial cells on these lobular-like scaffolds. Relatively long-term viability of hepatocyte/endothelial cells was found along with cell alignment and organization in vitro . The hepatocytes showed special epithelial polarity and bile duct formation, similar to the liver plate, while the aligned endothelial cells generated endothelial networks, similar to natural hepatic sinuses. This endowed the three-dimensional (3D) tissue constructs with the capability to recapitulate hepatic-like parenchymal-mesenchymal growth patterns in vitro . More importantly, the cocultured hepatocytes outperformed monocultures or monolayer cultures, displaying significantly enhanced hepatocyte functions, including functional gene expression, albumin (ALB) secretion, urea synthesis, and metabolic activity. Thus, this functional unit with a biomimetic phenotype provides a novel technology for bioengineering biomimetic hepatic lobules in vitro , with potential utility as a building block for bioartificial liver (BAL) engineering or as a robust tool for drug metabolism investigation.

Human induced pluripotent stem cells (hiPSC) are considered promising sources of pancreatic islet organoids to treat diabetes. Due to that epigenetic memory predisposes iPSCs to enhanced differentiation into the parental cell type, we sought to generate iPSC lines from islet cells isolated from healthy adult pancreata. Islet cells were reprogrammed with CytoTune-iPS 2.0 Sendai Reprogramming Kit, where the generated iPSCs showed normal karyotype, expression of pluripotency associated markers and in vivoteratoma formation. This cell line will be a valuable resource for drug screening, and potential source for high-efficient generation of insulin-producing islets for treating diabetes., (Copyright © 2021 The Authors. Published by Elsevier B.V. All rights reserved.)

Patients with familial hypercholesterolemia (FH) are susceptible to premature coronary artery disease. We generated a human iPSC line CIBi009-A from a patient with FH who carried variants of LDLR c.T1241G and APOB c.G1618T. This line will be a valuable resource for investigating novel therapeutic approaches to FH., (Copyright © 2021 The Author(s). Published by Elsevier B.V. All rights reserved.)

Galactose moieties are covalently coupled with sodium alginate to enhance liver-specific functions in microcapsules owing to the specific interaction between the galactose moieties and the asialoglycoprotein receptors (ASGPRs) of hepatocytes. In this study, galactosylated alginate (L-NH 2 -OH-alginate) based microcapsules with desirable stability and a suitable 3D microenvironment are designed and fabricated for primary hepatocyte applications. The designed L-NH 2 -OH-alginate is fabricated via the application of ethylenediamine grafted lactobionic acid (L-NH 2 ) onto the hydroxyl groups of sodium alginate so that the negatively charged carboxyl groups intact in L-NH 2 -OH-alginate can effectively bond with Ca 2+ to form a stable three-dimensional gel network; a subsequent reaction with polycations forms a stable membrane of microcapsules. As a result, L-NH 2 -OH-alginate based microcapsules exhibit an excellent mechanical stability. Moreover, with a higher degree of substitution in L-NH 2 -OH-alginate (DS 0.41), the hepatocytes entrapped in L-NH 2 -OH-alginate microcapsules exhibit better viability and well-maintained liver-specific functions., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Alginate-galactosylated chitosan/polylysine (AGCP) microcapsules with excellent stability and high permeability were developed and employed in primary hepatocyte applications. The galactosylated chitosan (GC), synthesized via the covalent coupling of lactobionic acid (LA) with low molecular weight and water-soluble chitosan (CS), was ingeniously introduced into the core of alginate microcapsules by regulating the pH of gelling bath. The internal GC of the microcapsules simultaneously provided a large number of binding sites for the hepatocytes and further promoted the hepatocyte-matrix interactions via the recognition of asialoglycoprotein receptors (ASGPRs) on the hepatocyte surface, and afforded the AGCP microcapsules an excellent stability via the electrostatic interactions with alginate. As a consequence, primary hepatocytes in AGCP microcapsules demonstrated enhanced viability, urea synthesis, albumin secretion, and P-450 enzyme activity, showing great prospects for hepatocyte applications in microcapsule system., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Indirect cell contact co-culture system is increasingly becoming more attractable owing to their advantages of easy cell separation and desirable outcomes for cell-cell interactions. However, how to precisely control the spatial position of cells within multicellular co-cultures is still experimentally challenging due to the incapability of the conventional methods in vitro. In the present study, a tunable collagen/alginate-chitosan (Col/Alg-Chi) membrane was established, which was capable of controlling intercellular distance between the neighboring cells at a level of micrometer resolution. It was showed that intercellular distance between the hepatocytes and the fibroblasts exerted significant influence on hepatic function in vitro. In particular, maintenance of the functionality of primary hepatocytes requires direct contact between the hepatocytes and their supportive stromal cells, and their effective contact distance is within 30μm. This technical platform would potentially enable investigations of dynamic cell-cell interaction in a multitude of applications including organogenesis, development or even neoplastic transformation., (Copyright © 2016. Published by Elsevier Ltd.)

Small-interfering RNA (siRNA)-mediated gene silencing with the aid of chitosan (CS)-based carriers has shown efficient and reliable outcome in vitro, but the gene silencing efficiency in vivo is still limited. It is of great importance to balance the protection and release of siRNA from nanoparticles (NPs) so as to achieve high efficiency. However, siRNA release profile from CS/siRNA NPs has been rarely concerned. Here, Förster resonance energy transfer technique was adopted for in vitro investigation of siRNA release from CS NPs in lysozyme-contained buffer. The results clearly showed that siRNA molecules experienced a fast and short release phase under lysozyme competition to both CS and siRNA, and then a slow and long release under lysozyme degradation on CS. Moreover, lysozyme competition played more important role than enzymolysis on trigging siRNA release. This preliminary study of siRNA release is the first step to get insight of in vivo siRNA release mechanism from CS/siRNA NPs, which will be helpful to adjust the design of CS/siRNA NPs for balancing the protection and release of siRNA molecules.

Hollow silica nanospheres with uniform size distribution and tuneable shell thickness were synthesized through a one-step reverse microemulsion method at room temperature within 24 h. These hollow nanospheres demonstrated effective encapsulation ability for FITC, Eu 3+ -complexes, iron oxide nanoparticles and chemotherapy drugs for potential imaging and drug delivery applications.

We report on an iconoclastic strategy for inhibiting proteases via autolysis acceleration. We show that proteases can be concentrated and induced to rapidly self-digest by a biocompatible polymer serving as an efficient catalyst. This new generation of protease inhibitors may find applications in the treatment of various protease-dependent diseases.

Sodium alginate (SA), acting as a trypsin inhibitor by means of electrostatic interaction, is studied. The half-maximal inhibitory concentration (IC50 = 0.05 μg mL(-1) ) of this natural anionic polymer is about 400 times lower than that of commercial soybean trypsin inhibitor (STI). Unlike the Ca(2+) -deprivation mechanisms, its inhibition may be attributed to preventing the trypsin active site (TAS) from accessing the macromolecular substrates instead of denaturing it. SA is an efficient, innocuous, and cost-effective inhibitory excipient that can be conveniently used in many peptide and protein dosage formulations., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Introduction: Islet purification is usually performed using the density gradient separation method, but the purity of islets is low because exocrine cells and the embedded islets are hard to remove by using only the density gradient method. The aim of this study was to establish a new islet purification process comprising a hypertonic-hypotonic treatment step followed by a density gradient centrifugation step to improve the purity of islets., Methods: The Plackett-Burman method was used to determine which factors had a significant influence on the purity of islets obtained after the hypertonic-hypotonic treatment step., Results: The hypertonic solution concentration and the incubation time were both found to have a significant effect on islet purity. The purity of islets obtained using the modified purification process was significantly higher than that of islets obtained by density gradient alone (97% vs. 87.23%). Importantly, good cell viability and normal insulin secretion ability of islets were maintained following the modified purification., Conclusions: The new purification process allows isolation of islets with improved purity and does not compromise the viability or function of the islets.