Present and future of in vitro immunotoxicology in drug development.

The realization, that the immune system can be the target of many chemicals including environmental contaminants and drugs with potentially adverse effects on the host's health, has raised serious concerns within the public and the regulatory agencies. At present, assessment of immunotoxic effects relies on different animal models and several assays have been proposed to characterize immunosuppression and sensitization. The use of whole animals, however, presents many secondary issues, such as expense, ethical concerns, and eventual relevance to risk assessment for humans. Furthermore, due to the new policy on chemicals (REACH), in the European Union, in vitro methods will play a major role in the near future. In addition, there is still a lack of human cell-based immunotoxicity assays for predicting the toxicity of xenobiotics toward the immune system in a simple, fast, economical, and reliable way. Hypersensitivity and immunosuppression, for which animal models have been developed and validated, are considered the primary focus for developing in vitro methods in immunotoxicology. Nevertheless, in vitro assays, as well as in vivo models, to detect immunostimulation and autoimmunity are also needed. Even if no validated alternative in vitro tests to assess immunotoxicity exist, in the last decade, much progress has been made toward these assays. Such models can be, at least, used for the pre-screening and hazard identification of unintended immunosuppression and contact hypersensitivity of direct immunotoxicants. Following a brief introduction to immunotoxicology and to in vivo models use to assess immunotoxicity, this manuscript will review the state-of-the-art in the field of in vitro immunotoxicity

alternative approach for potency assessment in vitro methods

Over the last decade, incredible progress has been made in the development of non-animal tests to assess contact hypersensitivity. Four methods have been successfully validated and Organisation for Economic Co-operation and Development (OECD) guidelines are available or soon will be. Currently validated methods are useful for hazard identification, classification and labeling. However, to achieve a complete replacement of animals in skin sensitization assessment, dose-response information and evaluation of relative skin sensitizing potency to support effective risk assessment are necessary. In this context, potency is based on the concentration of chemicals needed to induce a positive response. This will require a better understanding of the mechanisms determining potency, including pathway analysis and marker signature identification (selection of an appropriate immune-mediated response to serve as the basis), together with quantitative and qualitative correlations between marker signatures and potency of chemicals in relation with T cell responses. This review aims to discuss the state-of-the-art in the field of in vitro assessment of the no induction sensitization level of contact sensitizers

Establishment of an In Vitro Photoallergy Test Using NCTC2544 Cells and IL-18 Production

Differentiation between photoallergenic and phototoxic reactions induced by low molecular weight compounds represents a current problem. The use of eratinocytes as a potential tool for the detection of photoallergens as opposed to photoirritants is considered an interesting strategy for developing in vitro methods. We have previously demonstrated the possibility to use the human keratinocyte cell line NCTC2455 and the production of interleukin-18 (IL-18) to screen low molecular weight sensitizers. The purpose of this work was to explore the possibility to use the NCTC2544 assay to identify photoallergens and discriminate from phototoxic chemicals. First, we identified suitable condition of UV-irradiation (3.5 J/cm2) by investigating the effect of UVAirradiation on intracellular IL-18 on untreated or chloropromazine (a representative phototoxic compound)- treated NCTC2544 cells. Then, the effect of UVA-irradiation over NCTC2544 cells treated with increasing concentrations of 15 compounds including photoallergens (benzophenone, 4-ter-butyl-4-methoxydibenzoylmethane, 2-ethylexyl-p-methoxycinnamate, ketoprofen, 6-methylcumarin); photoirritant and photoallergen (4-aminobenzoic acid, chlorpromazine, promethazine); photoirritants (acridine, ibuprofen, 8-methoxypsoralen, retinoic acid); and negative compounds (lactic acid, SDS and p-phenilendiamine) was investigated. Twenty-four hours after exposure, cytotoxicity was evaluated by the MTT assay or LDH leakage, while ELISA was used to measure the production of IL-18. At the maximal concentration assayed with non-cytotoxic effects (CV80 under irradiated condition), all tested photoallergens induced a significant and a dose-dependent increase of intracellular IL-18 following UVA irratiation, whereas photoirritants failed. We suggest that this system may be useful for the in vitro evaluation of the photoallergic potential of chemicals

The Role of Ultrasonography in the Assessment of Skeletal Hand Involvement in Systemic Sclerosis

n/

Microplastic pollution in the Trieste Karst (Italy) protected habitats: preliminary analysis of cave and spring water sediments

Microplastic (MP) pollution in karst and subterranean areas is still poorly studied and research are generally focused on the water matrix. The Trieste Karst, Italy, is rich in peculiar karst habitats and species, including some endemics. To preserve these ecological heritages, different European, national and local laws are present. In this preliminary study we collected and investigated several sediment samples from aquatic environments in different protected habitats (three caves and a spring) of the Trieste Karst. Sediment samples were subjected to organic matter removal with 1:1 30% H2O2 solution and for each sample, three subsamples of 15g dried sediment were selected via coning and quartering. MPs were extracted from sediment via density separation and filtered. Particles on filters (5-0.1 mm) were counted and characterized by size, color and shape via visual identification under a microscope, with and without UV light, exploiting fluorescence given by additives added in many plastic materials. Finally, spectroscopic analyses were carried out on random particles on each filter. The concentration of MPs in cave water sediments varied from 911 to 2178 items/kg, instead, in the sediments of the spring it was of 889 items/kg. Fibre represented the most abundant shape (67.5%), followed by fragment (21.6%), bead (10%), and film (0.9%). Most MPs (86.4%) were smaller than 1 mm. The majority of the MPs were fluorescent under UV light (69.1%) and have 77.1% blue fluorescence, 8.1% red fluorescence, 6.1% green fluorescence and 8.7% other colors. Fluorescent particles were mainly transparent (63.8%), instead, in non-fluorescent ones predominated the black (56.2%) and brown (15.1%) MPs. Our results show the presence of MPs in all examined aquatic habitats, providing essential information for future research. The studied areas are adjacent to highways, roads and railways, therefore, most of the particles found in water sediment samples could come from surface pollution, transported by water and/or air. In addition, the waters of the sampling points are often stationary or poorly moved, therefore, there may be an accumulation of pollutants in the sediments. Vulnerable and troglobitic species hosted in these habitats could consume or assimilate MPs, which can irreversibly damage ecosystems and contaminate water resources too. Analyses on a greater number of aquatic surface and subterranean habitats should be done to better understand this kind of problem. Monitoring MPs pollution in karst areas should become a priority for the habitat conservation, the species protection and the water resources management

Experimental Paradigm for the Assessment of the Non-pharmacological Mechanism of Action in Medical Device Classification: The Example of Glycerine as Laxative

The evolution of medical devices has led to the introduction of medical devices that include “substances” and which, due to their presentation and sites of application may resemble medicinal products. The difference between substance-based medical devices and medicinal products lies in the proper definition of the principal mechanism of action. The major problem at the moment is the lack of a proper procedure for the demonstration of a mechanism that is “not pharmacological, immunological or metabolic.” We aimed to design an experimental set up to demonstrate the difference between the mechanism of action of two substances used commonly for the treatment of constipation, lubiprostone (example of medicinal product) and glycerine (example of medical device). By implementing cellular models and molecular analyses we demonstrate the difference in their mechanism of action. This set up can be considered an example on the possibility to define a paradigm for the case by case study of the mechanism of action of substances and combination of substances in medical devices

Filling the gap between the OR and virtual simulation : a European study on a basic neurosurgical procedure

Aki Laakso tutkimusryhmän jäsenenä.Currently available simulators are supposed to allow young neurosurgeons to hone their technical skills in a safe environment, without causing any unnecessary harm to their patients caused by their inexperience. For this training method to be largely accepted in neurosurgery, it is necessary to prove simulation efficacy by means of large-scale clinical validation studies. We correlated and analysed the performance at a simulator and the actual operative skills of different neurosurgeons (construct validity). We conducted a study involving 92 residents and attending neurosurgeons from different European Centres; each participant had to perform a virtual task, namely the placement of an external ventricular drain (EVD) at a neurosurgical simulator (ImmersiveTouch). The number of attempts needed to reach the ventricles and the accuracy in positioning the catheter were assessed. Data suggests a positive correlation between subjects who placed more EVDs in the previous year and those who get better scores at the simulator (p = .008) (fewer attempts and better surgical accuracy). The number of attempts to reach the ventricle was also analysed; senior residents needed fewer attempts (mean = 2.26; SD = 1.11) than junior residents (mean = 3.12; SD = 1.05) (p = .007) and staff neurosurgeons (mean = 2.89, SD = 1.23). Scoring results were compared by using the Fisher's test, for the analysis of the variances, and the Student's T test. Surprisingly, having a wider surgical experience overall does not correlate with the best performance at the simulator. The performance of an EVD placement on a simulator correlates with the density of the neurosurgical experience for that specific task performed in the OR, suggesting that simulators are able to differentiate neurosurgeons according to their surgical ability. Namely this suggests that the simulation performance reflects the surgeons' consistency in placing EVDs in the last year.Peer reviewe

Indici per la valutazione della qualit? ecologica dei laghi

Collection of methods to evaluate lake quality using biological element