High-yield recombinant adeno-associated viral vector production by multivariate optimization of bioprocess and transfection conditions.

Recombinant adeno-associated viral vectors (rAAVs) are one of the most used vehicles for gene therapy, with five rAAV therapeutics commercially approved by the FDA. To improve product yield, we optimized the suspension production process of rAAV8 vectors carrying a proprietary transgene using a commercially available transfection reagent, FectoVIR-AAV. Using a miniaturized automated 250 mL scale bioreactor system, we generated models of vector genome (vg) titer, capsid (cp) titer, and Vg:Cp percentage from two multivariate design of experiment studies, one centered around bioreactor operating parameters, and another based on the transfection conditions. Using the optimized process returned from these models, the vector genome titer from the bioreactor was improved to beyond 1 × 1012 vg/mL. Five critical parameters were identified that had large effects on the pre-purification vector quantity-the transfection pH, production pH, complexation time, viable cell density at transfection, and transfection reagent to DNA ratio. The optimized process was further assessed for its performance extending to six AAV serotypes, namely AAV1, AAV2, AAV5, AAV6, AAV8, and AAV9 carrying a transgene encoding for green fluorescent protein (GFP). Five of the six serotypes returned higher vector genome titers than the control condition. These data suggest that the choice of transfection reagent is a major factor in improving vector yield. The multivariate design of experiment approach is a powerful way to optimize production processes, and the optimized process from one AAV vector can to some extent be generalized to other serotypes and transgenes to accelerate development timelines of new programs.

The Putative Adverse Effects of Bisphenol A on Autoimmune Diseases.

Bisphenol A (BPA) is a monomer that is widely used in the manufacturing of polycarbonate plastics (including storage plastics and baby bottles) and is considered to be one of the most widely used synthetic compounds in the manufacturing industry. Exposure to BPA mainly occurs after oral ingestion and results from leaks into food and water from plastic containers. According to epidemiological data, exposure is widespread and estimated to occur in 90% of individuals. BPA exhibits pleiotropic and estrogen-like effects; thus, it is considered an endocrine-disrupting chemical. A growing body of evidence highlights the role of BPA in modulating immune responses and signaling pathways, which results in a proinflammatory response by enhancing the differential polarization of immune cells and cytokine production profile to one that is consistent with proinflammation. Indeed, epidemiological studies have uncovered associations between several autoimmune diseases and BPA exposure. Data from animal models provided consistent evidence, which highlighted the role of BPA in the pathogenesis, exacerbation, and perpetuation of various autoimmune phenomena including neuroinflammation in the context of multiple sclerosis, colitis in inflammatory bowel disease, nephritis in systemic lupus erythematosus, and insulitis in type 1 diabetes mellitus. Owing to the widespread use of BPA and its effects on immune system dysregulation, a call for careful assessment of patients' risks and public health measures are needed to limit exposure and subsequent deleterious effects. The purpose of this study is to explore the autoimmune triggering mechanisms and present the current literature supporting the role of BPA in the pathogenesis of autoimmune diseases.

Psychological stress and type 1 diabetes mellitus: what is the link?

INTRODUCTION: Type 1 diabetes mellitus (T1DM) is a chronic disease characterized by the destruction of insulin-producing ß-cells of the pancreas. The current paradigm in this disease's etiopathogenesis points toward the interplay of genetic and environmental factors. Among the environmental variables, dietary factors, intestinal microbiota, toxins, and psychological stress have been implicated in disease onset. Areas covered: This review aims to investigate the relationship between psychological stress and T1DM by presenting evidence from epidemiological studies, animal models, and to provide the mechanism involved in this association. The literature search was conducted through PubMed to identify studies that investigate the connection between stress and T1DM. Experimental designs, such as case-control, and retrospective and prospective cohorts studies, were included. Expert commentary: A wide array of evidence, ranging from epidemiological to animal models, points toward the role of psychological stressors in T1DM pathogenesis. Various mechanisms have been proposed, including the hypothalamic-pituitary-adrenal (HPA) axis, influence of the nervous system on immune cells, and insulin resistance. Further research could investigate the gene-stress interactions to evaluate the risk of T1DM development.

The role of stress in the mosaic of autoimmunity: An overlooked association.

Stress is defined as the pscyophysiological reaction in which the steady state is disturbed or threatened. Stress is not always perceived as a negative response. Stress results when environmental demands exceed an individuals' adaptive capacities. Autoimmune diseases are heterogeneous group of chronic diseases which occur secondary to loss of self antigen tolerance. The etiopathogenesis of autoimmune disease is uncertain. Genetic factors as well as environmental factors appear to interplay, leading to a cascade of events resulting in disease onset. Stress has been postulated to play a role in disease onset in the genetically susceptible patients. During the stress response, catecholamines and glucocorticoids are released from locus coeruleus and adrenal gland. These biomolecules exert control over various immune cells in the innate and adaptive arms of the immune system, thereby altering the cytokine profile released. The increase of IL-4 promotes T-helper 2 (Th2) cell differentiation, while the decrease in IL-12 and the increased IL-10 production reduce the number of T-helper 1 (Th1) cells. The relationship between stress and autoimmune diseases is intricate. Stress has been shown to be associated with disease onset, and disease exacerbations in rheumatoid arthritis, systemic lupus erythematosus, inflammatory bowel disease, multiple sclerosis, Graves' disease as well as other autoimmune conditions. In certain conditions such as psoriasis, stress has been implicated in delaying lesion clearance upon the application of standard treatment regimes. Finally, psychological therapy and cognitive behavioral therapy aimed to reduce stress levels was shown to be effective in influencing better outcomes in many autoimmune diseases. The purpose of this paper is to closer inspect the clinical evidence regarding the role of stress on influencing the various aspects of disease entities.

Blood brain barrier: A review of its anatomy and physiology in health and disease.

The blood-brain barrier (BBB) is the principal regulator of transport of molecules and cells into and out of the central nervous system (CNS). It comprises endothelial cells, pericytes, immune cells, astrocytes, and basement membrane, collectively known as the neurovascular unit. The development of the barrier involves many complex pathways from all the progenitors of the neurovascular unit, but the timing of its formation is not entirely known. The coordinated activities of all the components of the neurovascular unit and other tissues ensure that materials required for growth and maintenance are allowed into the CNS while extraneous ones are excluded. This review summarizes current knowledge of the anatomy, development, and physiology of the BBB, and alterations that occur in disease conditions. Clin. Anat. 31:812-823, 2018. © 2018 Wiley Periodicals, Inc.