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Gene therapy has the potential to maintain therapeutic blood clotting factor IX (FIX) levels in patients with hemophilia B by delivering a functional human F9 gene into liver cells. This phase 1/2, open-label dose-escalation study investigated BAX 335 (AskBio009, AAV8.sc-TTR-FIXR338Lopt), an adeno-associated virus serotype 8 (AAV8)-based FIX Padua gene therapy, in patients with hemophilia B. This report focuses on 12-month interim analyses of safety, pharmacokinetic variables, effects on FIX activity, and immune responses for dosed participants. Eight adult male participants (aged 20-69 years; range FIX activity, 0.5% to 2.0%) received 1 of 3 BAX 335 IV doses: 2.0 × 1011; 1.0 × 1012; or 3.0 × 1012 vector genomes/kg. Three (37.5%) participants had 4 serious adverse events, all considered unrelated to BAX 335. No serious adverse event led to death. No clinical thrombosis, inhibitors, or other FIX Padua-directed immunity was reported. FIX expression was measurable in 7 of 8 participants; peak FIX activity displayed dose dependence (32.0% to 58.5% in cohort 3). One participant achieved sustained therapeutic FIX activity of ∼20%, without bleeding or replacement therapy, for 4 years; in others, FIX activity was not sustained beyond 5 to 11 weeks. In contrast to some previous studies, corticosteroid treatment did not stabilize FIX activity loss. We hypothesize that the loss of transgene expression could have been caused by stimulation of innate immune responses, including CpG oligodeoxynucleotides introduced into the BAX 335 coding sequence by codon optimization. This trial was registered at www.clinicaltrials.gov as #NCT01687608., (© 2021 by The American Society of Hematology.)

Hemophilia is a congenital bleeding disorder that affects nearly half a million individuals worldwide. Joint bleeding and other co-morbidities are a significant source of debilitation for this population. Current therapies are effective but must be given lifelong at regular intervals, are costly, and are available to only about 25% of the hemophilia population living in resource-rich countries. Gene therapy for hemophilia has been in development for three decades and is now entering pivotal-stage clinical trials. While many different technology platforms exist for gene therapy, all current clinical trials for hemophilia employ adeno-associated vector (AAV)-based cell transduction. This small viral particle is capable of packaging modified F8 or F9 transgenes, can be generated robustly from cell lines, and transduces several relatively end-differentiated target tissues such as the liver with high efficiency. While pre-existing neutralizing antibodies to the AAV capsid are recognized to limit current therapy, other challenges have been identified in human studies that were not seen in preclinical studies. Both liver transaminase elevations and immune-mediated loss of transgene expression have been observed in clinical trials. Toll-like receptors, cytotoxic T cells, and other components of the immune response have been implicated in the loss of factor expression, but a full understanding of the immune response awaits clarification. Despite these challenges, many patients enrolled in gene therapy trials have attained long-term expression of factors VIII and IX. This emerging technology now represents a cure for the severe bleeding and joint damage associated with hemophilia.

Fibrin plays an essential role in hemostasis as both the primary product of the coagulation cascade and the ultimate substrate for fibrinolysis. Fibrinolysis efficiency is greatly influenced by clot structure, fibrinogen isoforms and polymorphisms, the rate of thrombin generation, the reactivity of thrombus-associated cells such as platelets, and the overall biochemical environment. Regulation of the fibrinolytic system, like that of the coagulation cascade, is accomplished by a wide array of cofactors, receptors, and inhibitors. Fibrinolytic activity can be generated either on the surface of a fibrin-containing thrombus, or on cells that express profibrinolytic receptors. In a widening spectrum of clinical disorders, acquired and congenital defects in fibrinolysis contribute to disease morbidity, and new assays of global fibrinolysis now have potential predictive value in multiple clinical settings. Here, we summarize the basic elements of the fibrinolytic system, points of interaction with the coagulation pathway, and some recent clinical advances., (Copyright © 2014. Published by Elsevier Ltd.)

Pyrogallol[4]arene is a macrocycle with a concave surface and 12 peripheral hydroxyl groups that mediate its self-assembly to form hexamers of octahedral symmetry in the solid state, in solution, and in the gas phase. These hexamers enclose approximately 1300 Å(3) of space, which is filled with small molecules. In this study, we show that solvent-free conditions for guest entrapment in these hexamers, using molten guest molecules as solvent and allowing the capsules to assemble during cooling, results in exceptionally kinetically stable encapsulation complexes that are not formed in the presence of solvent and are not thermodynamically stable. The capsules' kinetic stabilities are strongly dependent on the size and shape of both guest and solvent molecules, with larger or nonplanar molecules with rigid geometries providing enhanced stability. The greatest observed barrier to guest exchange, ΔG(‡) = 32 ± 0.7 kcal mol(-1) for encapsulated CCl(4) → encapsulated pyrene, is, to the best of our knowledge, indicative of the most powerful kinetic trap ever observed for a synthetic, hydrogen-bonded encapsulation complex. Detailed NMR studies of the structures of the assemblies and the kinetics and mechanisms for guest exchange reveal that subtle differences in guest and solvent structure can impart profound effects on the behavior of the systems. Kinetic and thermodynamic stability, capsule symmetry and structure, guest tumbling rates, susceptibility to disruption by polar solvents, and even the mechanism for equilibration-the presence or absence of supramolecular intermediates-are all greatly influenced. The strongest observed kinetic traps provide encapsulation complexes that are not at equilibrium but are nonetheless indefinitely persistent at ambient temperatures, a property that invites future applications of supramolecular chemistry in open systems where equilibrium is not possible.

Background: Neural crest stem cells may hold potential as a cellular therapeutic to repopulate the enteric nervous system. The expression of the low-affinity nerve growth factor receptor, p75, may enrich enteric cells isolated from the neonatal rodent intestinal tract for neural crest stem cells. While these cells have shown tremendous promise in vitro, it remains to be determined whether they will survive and differentiate after in vivo transplantation., Materials and Methods: Cells isolated from the neonatal rodent intestinal muscularis were sorted according to their degree of p75 expression. The parent, p75-high, and p75-low expressing populations were injected into the rodent stomach for 7 d in vivo., Results: Cells that expressed high levels of p75 also expressed high levels of nestin. Evaluation of the parent, p75-high, and p75-low populations of cells showed 420-, 130-, and 20-fold growth, respectively, after 11 d of culture. Transplantation of these populations of cells into syngeneic rodent stomachs showed cell survival in the injection site after 7 d. Cells expressing either the neuronal marker, peripherin, or the glial marker, S100, were present in and around the injection site when the parent and the p75-high populations were transplanted., Conclusions: Enteric cells survive transplantation into the rodent stomach and induce the expression of differentiation markers in and around the injection site. Based on these results, enteric cells may hold potential as a cellular therapeutic in a variety of gastrointestinal disorders., (Copyright © 2012 Elsevier Inc. All rights reserved.)

The authors studied the effects of pancuronium, 14--200 micrograms/kg, on epinephrine-induced arrhythmias (premature ventricular contractions) in dogs anesthetized with halothane, 1.4 MAC. Neither muscle relaxant significantly affected the arrhythmogenic dose of epinephrine. This finding indicates that the usual guidelines for the administration of epinephrine during halothane anesthesia are not affected by concomitant administration of the two nondepolarizing muscle relaxants studied.

Arrhythmogenic doses of epinephrine were determined in six mongrel dogs anesthetized at 1.4 MAC halothane initially in the absence of local anesthetics and then at increasing arterial plasma levels of lidocaine, bupivacaine, and etidocaine. The authors gave epinephrine intravenously at 5 microgram/kg/min and calculated the arrhythmogenic dose as a function of time until two or more premature ventricular contractions occurred within a 10-sec period. The control arrythmogenic dose of epinephrine was 4.66 +/- 0.46 microgram/kg (mean +/- SEM). Arrythmogenic doses of epinephrine were increased significantly after each dose of lidocaine, bupivacaine, and etidocaine. With the largest doses studied, local anesthetic plasma levels were frequently in the toxic range. The data show that lidocaine, bupivacaine, and etidocaine equally protect against epinephrine-induced arrhythmias in dogs anesthetized with halothane.

The minimum alveolar concentration (MAC) of aliflurane was measured in ten dogs. A value of 1.84 volumes per cent was determined, which correlates well with predictions based on lipid solubility. Induction of anesthesia and recovery were rapid, as would be anticipated with an agent of relatively low solubility in blood (blood-gas partition coefficient = 1.7). Circulatory responses over a relatively narrow range of aliflurane concentrations (0.8 to 1.4 MAC) remained stable, but the development of tachypnea, irregular ventilatory patterns, and increased muscle tone were frequently encountered during aliflurane anesthesis.

Transmission of airway pressure to the intrapleural space and change in functional residual capacity by positive end-expiratory pressure (PEEP) were measured in ten anesthetized swine. Measurements and calculations were performed with varying lung and chest wall compliances. When both compliances were normal, approximately half of the applied airway pressure was transmitted. Aspiration of hydrochloric acid reduced lung compliance approximately fourfold and decreased airway pressure transmission. Increased thoracic compliance also reduced airway pressure transmission. When acid aspiration reduced lung compliance and sternotomy simultaneously increased thoracic compliance, pressure transmission was maximally reduced. Decreases in either thoracic or lung compliance reduced the volume-expanding effects of PEEP. Positive end-expiratory pressure was least effective when thoracic and lung compliances were reduced simultaneously. Careful assessment of both lung and thoracic compliances may be helpful in treating patients requiring elevated airway pressure.