ABSTRACT
BACKGROUND: Neuromyelitis optica spectrum disorder (NMOSD) is a rare autoimmune neurological disorder associated with antibodies to aquaporin-4 (AQP4). NMOSD has been thought to follow a progressive disease course, with step-wise accumulation of disability over time, even in patients undergoing immunosuppressive/immunomodulatory therapy. The influence of factors such as AQP4 seropositivity, AQP4 serum titer levels, and administration of plasmapheresis on NMOSD prognosis is, as yet, unclear. METHODS: We performed a retrospective chart review of 53 persons with NMOSD at Duke University Hospital-collecting data on longitudinal disease course, imaging, demographics, and serum AQP4 titers (measured using the ELISA or FACS method). Most patients in our cohort were treated with high-dose corticosteroids and, following diagnosis, received maintenance immunosuppressive/immunomodulatory therapies. Longitudinal data on EDSS scores were used to calculate the slope of disability over time for each participant. We additionally investigated the correlation between initial AQP4 seropositivity, initial AQP4 serum titer levels, and treatment with plasmapheresis on disability progression for each participant. RESULTS: Contrary to current views on NMOSD disease course, the majority of our participants showed either no change (31.9%) or improvement (27.1%) in disability over time. Our results additionally revealed no significant association between clinical prognosis and initial AQP4 seropositivity (p = 0.830), initial AQP4 serum titer levels (p = 0.338), or administration of plasmapheresis (p = 0.1149). CONCLUSIONS: Our study presents a contemporary view of the clinical course of NMOSD and shows a more favorable view of its disease course than prior studies (performed before high-efficacy disease modifying therapies became widely-used for this patient population). Most patients in this study received treatment with high-dose corticosteroids following NMOSD flares, as well as a variety of maintenance immunosuppressive therapies. The results of this study cannot shed light on the disease course of untreated NMOSD. Our findings additionally challenge the theory that AQP4 seropositivity or serum titer levels at time of diagnosis may be used to effectively predict NMOSD prognosis. While we were unable to find evidence supporting a favorable effect of plasmapheresis administration on disease outcomes, further research is needed to determine the role plasmapheresis ought to play in the treatment of NMOSD.
Subject(s)
Neuromyelitis Optica , Humans , Neuromyelitis Optica/diagnosis , Neuromyelitis Optica/therapy , Retrospective Studies , Prognosis , Aquaporin 4 , Disease Progression , AutoantibodiesABSTRACT
BACKGROUND: New strategies for improving durable functional islet mass will be instrumental in facilitating islet transplantation as a cure for type 1 diabetes mellitus. The ability to transfer immunoregulatory or cytoprotective genes into pancreatic islets may enhance survival. Adenoviral vectors (Ad5) have been used widely to deliver therapeutic genes to different tissues. Limitations associated with the use of Ad5 for gene therapy are related to the reliance of the virus on the presence of its primary receptor, the transient nature of the transgene expression, and the immediate inflammatory and immune response elicited by the infection. Because the arginine-glycine-aspartame (RGD) and polylysine (pK7) motifs have been shown to enhance Ad5 infection through an Ad5 receptor-independent pathway, we hypothesized that they could act additively to improve infectivity and reduce toxicity to isolated human pancreatic islets (IHPI). METHODS: Hand-picked IHPI were infected with nonmodified Ad5, single-modified Ad5 with RGD (Ad5RGD) or pK7 (ad5pK7), and Ad5RGDpK7. Transfection efficiency was evaluated by green fluorescent protein and luciferase expression. Apoptosis was assessed using a quantitative assay, activation of caspase 3 by a colorimetric assay, nuclear factor (NF)-kappaB nuclear translocation using a promoter-luciferase NF-kappaB responsive construct, regulated on activation normal T-cell expressed and secreted (RANTES) by enzyme-linked immunosorbent assay. In vivo functionality was evaluated after transplantation into diabetic nonobese diabetic severe combined immunodeficiency mice. RESULTS: Compared with unmodified and singly-modified Ad5 vectors, Ad5RGDpK7 demonstrated the highest infectivity. After the infection of IHPI with adenoviral vectors using the minimal dose required to infect greater than 80% of the islet cells (Ad5, 500 viral particles [VP]/cell; Ad5RGD and Ad5pK7, 10 VP/cell; Ad5RGDpK7, 0.1 VP/cell), islets infected with Ad5RGDpK7 presented a significant reduction in apoptosis, NF-kappaB nuclear translocation, RANTES expression, and higher glucose disposal rate; reduced Ad5-driven specific Th1 and antibody response were also observed. CONCLUSIONS: Ad5RGDpK7 exhibited higher transfection efficiency, allowing a significant reduction in the viral dose required to infect greater than 80% of the islet cells. The reduction in the viral dose was associated with reduced toxicity, inflammation, and immune responses related to Ad5 infection. This strategy may thus be used to successfully modify isolated pancreatic islets.