A RNA Dodecahedral Cage Inside a Human Virus Plays a Dual Biological Role in Virion Assembly and Genome Release Control.

Human rhinoviruses (RV) are among the most frequent human pathogens. As major causative agents of common colds they originate serious socioeconomic problems and huge expenditure every year, and they also exacerbate severe respiratory diseases. No anti-rhinoviral drugs or vaccines are available so far.

Single-Molecule Analysis of Genome Uncoating from Individual Human Rhinovirus Particles, and Modulation by Antiviral Drugs.

Infection of humans by many viruses is typically initiated by the internalization of a single virion in each of a few susceptible cells. Thus, the outcome of the infection process may depend on stochastic single-molecule events. A crucial process for viral infection, and thus a target for developing antiviral drugs, is the uncoating of the viral genome.

Electrostatic Screening, Acidic pH and Macromolecular Crowding Increase the Self-Assembly Efficiency of the Minute Virus of Mice Capsid In Vitro.

The hollow protein capsids from a number of different viruses are being considered for multiple biomedical or nanotechnological applications. In order to improve the applied potential of a given viral capsid as a nanocarrier or nanocontainer, specific conditions must be found for achieving its faithful and efficient assembly in vitro. The small size, adequate physical properties and specialized biological functions of the capsids of parvoviruses such as the minute virus of mice (MVM) make them excellent choices as nanocarriers and nanocontainers.

Molecular Determinants of Human Rhinovirus Infection, Assembly, and Conformational Stability at Capsid Protein Interfaces.

Human rhinovirus (HRV), one of the most frequent human pathogens, is the major causative agent of common colds. HRVs also cause or exacerbate severe respiratory diseases, such as asthma or chronic obstructive pulmonary disease. Despite the biomedical and socioeconomic importance of this virus, no anti-HRV vaccines or drugs are available yet.

Optimization and validation of a chiral CE-LIF method for quantitation of aspartate, glutamate and serine in murine osteocytic and osteoblastic cells.

Asp, Glu, and D-Ser are chiral amino acids and neurotransmitters binding to the N-methyl-D-aspartate receptor (NMDA) and they participate in glutamate signalization. D-amino acids are increasingly being recognized as important signaling molecules and variations in their levels are considered a marker of different pathologies, however, there is still a lack of knowledge about the role of most of D-amino acids in living organisms such as bone cells. A method for determination of concentrations of L/D-Asp, L/D-Glu and L/D-Ser in two types of bone cell lines: murine osteocytes (MLOY4) and osteoblasts (MC3T3-E1) is presented.

Pancreatic human islets and insulin-producing cells derived from embryonic stem cells are rapidly identified by a newly developed Dithizone.

We developed an optimized Dipheylthiocarbazone or Dithizone (DTZ) with improved physical and chemical properties to characterize human islets and insulin-producing cells differentiated from embryonic stem cells. Application of the newly formulated iDTZ (i stands for islet) over a range of temperatures, time intervals and cell and tissue types found it to be robust for identifying these cells. Through high transition zinc binding, the iDTZ compound concentrated in insulin-producing cells and proved effective at delineating zinc levels in vitro.

Evaluation of collagenase gold plus BP protease in isolating islets from human pancreata.

Selection of enzymes for optimal pancreas digestion is essential for successful human islet isolations. The aim of this study was to evaluate the efficacy and outcome of using Collagenase Gold plus BP protease (VitaCyte) (n = 8) by comparing it to two commercially available enzymes, Liberase MTF C/T (Roche) (n = 48) and Collagenase NB1/NP (Serva) (n = 15). The isolation outcomes were assessed by islet counting, viability, glucose-stimulated oxygen consumption rate (OCR), and successful graft-rate following transplantation in diabetic NOD scid mice.

Involvement of a proapoptotic gene (BBC3) in islet injury mediated by cold preservation and rewarming.

Long-term pancreatic cold ischemia contributes to decreased islet number and viability after isolation and culture, leading to poor islet transplantation outcome in patients with type 1 diabetes. In this study, we examined mechanisms of pancreatic cold preservation and rewarming-induced injury by interrogating the proapoptotic gene BBC3/Bbc3, also known as Puma (p53 upregulated modulator of apoptosis), using three experimental models: 1) bioluminescence imaging of isolated luciferase-transgenic ("Firefly") Lewis rat islets, 2) cold preservation of en bloc-harvested pancreata from Bbc3-knockout (KO) mice, and 3) cold preservation and rewarming of human pancreata and isolated islets. Cold preservation-mediated islet injury occurred during rewarming in "Firefly" islets.

Prophylactically Decontaminating Human Islet Product for Safe Clinical Application: Effective and Potent Method.

Background: Transplanting pancreatic islets into recipients must be safe and effective to treat Type 1 diabetes. Islet quality and quantity are important, however, the final product must also be free from microbial contamination and low endotoxin levels.

Methods: This study explored a method to eliminate contamination in manufacturing islets for transplantation.

The Choice of Enzyme for Human Pancreas Digestion is a Critical Factor for Increasing the Success of Islet Isolation.

Background: We evaluated three commercially available enzymes for pancreatic digestion by comparing key parameters during the islet isolation process, as well as islet quality post-isolation.

Methods: Retrospectively compared and analyzed islet isolations from pancreata using three different enzyme groups: Liberase HI (n=63), Collagenase NB1/Neutral Protease (NP) (n=43), and Liberase Mammalian Tissue Free Collagenase/Thermolysin (MTF C/T) (n=115). A standardized islet isolation and purification method was used.

Sodium levels of human pancreatic donors are a critical factor for determination of islet efficacy and survival.

Organs from hypernatremia (elevated Na+) donors when used for transplantation have had dismal outcomes. However, islet isolation from hypernatremic donors for both transplantation and research applications has not yet been investigated. A retrospective analysis of in vivo and in vitro islet function studies was performed on islets isolated from hypernatremic (serum sodium levels≥160 meq/l) and normal control (serum sodium levels≤155 meq/l) donors.

Human Pancreatic Islets Isolated From Donors With Elevated HbA1c Levels: Islet Yield and Graft Efficacy.

Unlabelled: The aim of this study was to investigate the effects of elevated donor HbA1c levels (type 2 diabetes, T2D) on the islet yield and functionality postisolation. In this retrospective analysis, donors for islet isolations were classified into two groups: T2D group (HbA1c ≥ 6.5%, n = 18) and normal group (HbA1c < 6.

The effects of digestion enzymes on islet viability and cellular composition.

The choice of enzyme blend is critical for successful islet isolation. Islet yield, viability, integrity, and function are important factors that influence the outcome of islet transplantation. Liberase HI has been used as a standard enzyme for pancreas digestion and has successfully produced islets that reversed diabetes.

Quantitative assessment of β-cell apoptosis and cell composition of isolated, undisrupted human islets by laser scanning cytometry.

Background: Assays for assessing human islet cell quality, which provide results before transplantation, would be beneficial to improve the outcomes for islet transplantation therapy. Parameters such as percent β-cell apoptosis and cell composition are found to vary markedly between different islet preparations and may serve as markers of islet quality. We have developed fluorescence-based assays using laser scanning cytometry for assessing β-cell apoptosis and islet cell composition on serial sections of intact isolated islets.

Generation of human islets through expansion and differentiation of non-islet pancreatic cells discarded (pancreatic discard) after islet isolation.

Objectives: Islet transplantation is hampered by the shortage of donor tissues. Our objective was to generate islet-like cell clusters (ICCs) from cultures of non-islet pancreatic cells.

Methods: The starting cultured cells came from the non-islet fractions of human pancreases after enzymatic digestion and purification for the purpose of islet isolation.

Inhibition of p38 pathway suppresses human islet production of pro-inflammatory cytokines and improves islet graft function.

Nonspecific inflammation is associated with primary graft nonfunction (PNF). Inflammatory islet damage is mediated at least partially by pro-inflammatory cytokines, such as interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha) produced by resident islet macrophages. The p38 pathway is known to be involved in cytokine production in the cells of the monocyte-macrophage lineage.