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Replication-competent adenoviruses armed with thymidine kinase (TK) combine the concepts of virotherapy and suicide gene therapy. Moreover TK-activity can be detected by noninvasive positron emission-computed tomography (PET) imaging, what could potentially facilitate virus monitoring in vivo. Here, we report the generation of a novel oncolytic adenovirus that incorporates the Tat8-TK gene under the control of the Major Late Promoter in a highly selective backbone thus providing selectivity by targeting the retinoblastoma pathway. The selective oncolytic TK virus, termed ICOVIR5-TK-L, showed reduced potency compared to a non-selective counterpart. However the combination of ICOVIR5-TK-L with ganciclovir (GCV) induced a potent antitumoural effect similar to that of wild type adenovirus in a preclinical model of pancreatic cancer. Although the treatment with GCV provoked a reduction in the viral yield, both in vitro and in vivo, a two-cycle treatment of virus and GCV resulted in an enhanced antitumoral response that correlated with high TK-activity, based on microPET measurements. Thus, TK-expressing oncolytic adenoviruses can be traced by PET imaging providing real time information on the activity of the virus and its antitumoral potency can be optimized by GCV dosing.

Abstract Background Skeletal muscle injury characterisation during healing supports trauma prognosis. Given the potential interest of computed tomography (CT) in muscle diseases and lack of in vivo CT methodology to image skeletal muscle wound healing, we tracked skeletal muscle injury recovery using in vivo micro-CT in a rat model to obtain a predictive model. Methods Skeletal muscle injury was performed in 23 rats. Twenty animals were sorted into five groups to image lesion recovery at 2, 4, 7, 10, or 14 days after injury using contrast-enhanced micro-CT. Injury volumes were quantified using a semiautomatic image processing, and these values were used to build a prediction model. The remaining 3 rats were imaged at all monitoring time points as validation. Predictions were compared with Bland-Altman analysis. Results Optimal contrast agent dose was found to be 20 mL/kg injected at 400 μL/min. Injury volumes showed a decreasing tendency from day 0 (32.3 ± 12.0mm3, mean ± standard deviation) to day 2, 4, 7, 10, and 14 after injury (19.6 ± 12.6, 11.0 ± 6.7, 8.2 ± 7.7, 5.7 ± 3.9, and 4.5 ± 4.8 mm3, respectively). Groups with single monitoring time point did not yield significant differences with the validation group lesions. Further exponential model training with single follow-up data (R 2 = 0.968) to predict injury recovery in the validation cohort gave a predictions root mean squared error of 6.8 ± 5.4 mm3. Further prediction analysis yielded a bias of 2.327. Conclusion Contrast-enhanced CT allowed in vivo tracking of skeletal muscle injury recovery in rat.

Gold-ceria nanoparticles (Au/CeO2) are known to have antioxidant properties. However, whether these nanoparticles can provide benefits in type 2 diabetes mellitus (T2D) remains unknown. This work aimed to study the effects of Au/CeO2 nanoparticles at different rates of gold purity (10, 4.4, 1.79 and 0.82) on leukocyte–endothelium interactions and inflammation in T2D patients. Anthropometric and metabolic parameters, leukocyte–endothelium interactions, ROS production and NF-κB expression were assessed in 57 T2D patients and 51 healthy subjects. T2D patients displayed higher Body Mass Index (BMI) and characteristic alterations in carbohydrate and lipid metabolism. ROS production was increased in leukocytes of T2D patients and decreased by Au/CeO2 at 0.82% gold. Interestingly, Au/CeO2 0.82% modulated leukocyte–endothelium interactions (the first step in the atherosclerotic process) by increasing leukocyte rolling velocity and decreasing rolling flux and adhesion in T2D. A static adhesion assay also revealed diminished leukocyte–endothelium interactions by Au/CeO2 0.82% treatment. NF-κB (p65) levels increased in T2D patients and were reduced by Au/CeO2 treatment. Cell proliferation, viability, and apoptosis assays demonstrated no toxicity produced by Au/CeO2 nanoparticles. These results demonstrate that Au/CeO2 nanoparticles at 0.82% exert antioxidant and anti-inflammatory actions in the leukocyte–endothelium interaction of T2D patients, suggesting a protective role against the appearance of atherosclerosis and cardiovascular diseases when this condition exists.

An amendment to this paper has been published and can be accessed via the original article.

Human peripheral blood cells are relevant ex vivo models for characterizing diseases and evaluating the pharmacological effects of therapeutic interventions, as they provide a close reflection of an individual pathophysiological state. In this work, a new approach to evaluate the impact of nanoparticles on the three main fractions of human peripheral blood cells by nuclear magnetic resonance spectroscopy is shown. Thus, a comprehensive protocol has been set-up including the separation of blood cells, their in vitro treatment with nanoparticles and the extraction and characterization of metabolites by nuclear magnetic resonance. This method was applied to assess the effect of gold nanoparticles, either coated with chitosan or supported on ceria, on peripheral blood cells from healthy individuals. A clear antioxidant effect was observed for chitosan-coated gold nanoparticles by a significant increase in reduced glutathione, that was much less pronounced for gold-cerium nanoparticles. In addition, the analysis revealed significant alterations of several other pathways, which were stronger for gold-cerium nanoparticles. These results are in accordance with the toxicological data previously reported for these materials, confirming the value of the current methodology.

[This corrects the article DOI: 10.1371/journal.pone.0182985.].