Nano(bio)Materials Do Not Affect Macrophage Phenotype-A Study Conducted by the REFINE Project.

Macrophages are well known for their involvement in the biocompatibility, as well as biodistribution, of nano(bio)materials. Although there are a number of rodent cell lines, they may not fully recapitulate primary cell responses, particularly those of human cells. Isolation of tissue-resident macrophages from humans is difficult and may result in insufficient cells with which to determine the possible interaction with nano(bio)materials.

Transferability and reproducibility of exposed air-liquid interface co-culture lung models.

Background: The establishment of reliable and robust in vitro models for hazard assessment, a prerequisite for moving away from animal testing, requires the evaluation of model transferability and reproducibility. Lung models that can be exposed via the air, by means of an air-liquid interface (ALI) are promising in vitro models for evaluating the safety of nanomaterials (NMs) after inhalation exposure. We performed an inter-laboratory comparison study to evaluate the transferability and reproducibility of a lung model consisting of the human bronchial cell line Calu-3 as a monoculture and, to increase the physiologic relevance of the model, also as a co-culture with macrophages (either derived from the THP-1 monocyte cell line or from human blood monocytes).

Application of KU812 cells for assessing complement activation related effects by nano(bio)materials.

Immunocompatibility issues related to nano(bio)materials, particularly liposomal formulations, involving activation of the complement system have been relatively well described however, they highlight the importance of preclinical evaluation of such interactions. These complement-mediated hypersensitivity reactions, in which basophils are implicated, are associated with complement activation-related pseudoallergy (CARPA). Ex vivo investigation of such events using primary basophils is technically challenging due to the relatively limited number of circulating basophils in peripheral blood.

Development of a cell line-based in vitro assay for assessment of Diphtheria, Tetanus and acellular Pertussis (DTaP)-induced inflammasome activation.

Safety and potency assessment for batch release testing of established vaccines still relies partly on animal tests. An important avenue to move to batch release without animal testing is the consistency approach. This approach is based on thorough characterization of the vaccine to identify critical quality attributes that inform the use of a comprehensive set of non-animal tests to release the vaccine, together with the principle that the quality of subsequent batches follows from their consistent production.

An inter-laboratory comparison of an NLRP3 inflammasome activation assay and dendritic cell maturation assay using a nanostructured lipid carrier and a polymeric nanomedicine, as exemplars.

Nanoparticles including nanomedicines are known to be recognised by and interact with the immune system. As these interactions may result in adverse effects, for safety evaluation, the presence of such interactions needs to be investigated. Nanomedicines in particular should not unintendedly interact with the immune system, since patient's exposure is not minimised as in the case of 'environmental' nanoparticles, and repeated exposure may be required.

Evaluation of Adverse Effects of Resorbable Hyaluronic Acid Fillers: Determination of Macrophage Responses.

Resorbable tissue fillers for aesthetic purposes can induce severe complications including product migration, late swelling, and inflammatory reactions. The relation between product characteristics and adverse effects is not well understood. We hypothesized that the degree of cross-linking hyaluronic acid (HA) fillers was associated with the occurrence of adverse effects.

Standardization of an in vitro assay matrix to assess cytotoxicity of organic nanocarriers: a pilot interlaboratory comparison.

Nanotechnologies such as nanoparticles are established components of new medical devices and pharmaceuticals. The use and distribution of these materials increases the requirement for standardized evaluation of possible adverse effects, starting with a general cytotoxicity screening. The Horizon 2020 project "Regulatory Science Framework for Nano(bio)material-based Medical Products and Devices (REFINE)" identified in vitro cytotoxicity quantification as a central task and first step for risk assessment and development for medical nanocarriers.

Pathways Related to NLRP3 Inflammasome Activation Induced by Gold Nanorods.

The widespread and increasing use of engineered nanomaterials (ENM) increases the risk of human exposure, generating concern that ENM may provoke adverse health effects. In this respect, their physicochemical characteristics are critical. The immune system may respond to ENM through inflammatory reactions.

An Air-liquid Interface Bronchial Epithelial Model for Realistic, Repeated Inhalation Exposure to Airborne Particles for Toxicity Testing.

For toxicity testing of airborne particles, air-liquid interface (ALI) exposure systems have been developed for in vitro tests in order to mimic realistic exposure conditions. This puts specific demands on the cell culture models. Many cell types are negatively affected by exposure to air (e.

The crystal structure of titanium dioxide nanoparticles influences immune activity in vitro and in vivo.

Background: The use of engineered nanoparticles (NP) is widespread and still increasing. There is a great need to assess their safety. Newly engineered NP enter the market in a large variety; therefore safety evaluation should preferably be in a high-throughput fashion.

A Dose-Response Modeling Approach Shows That Effects From Mixture Exposure to the Skin Sensitizers Isoeugenol and Cinnamal Are in Line With Dose Addition and Not With Synergism.

Currently, hazard characterization of skin sensitizers is based on data obtained from studies examining single chemicals. Many consumer products, however, contain mixtures of sensitizers that might interact in such a way that the response induced by a substance is higher than predicted in the hazard assessment. To assess interaction of skin sensitizers in a mixture, a dose-response modeling approach is applied.

In vitro effects of aldehydes present in tobacco smoke on gene expression in human lung alveolar epithelial cells.

Tobacco smoke consists of thousands of harmful components. A major class of chemicals found in tobacco smoke is formed by aldehydes, in particular formaldehyde, acetaldehyde and acrolein. The present study investigates the gene expression changes in human lung alveolar epithelial cells upon exposure to formaldehyde, acrolein and acetaldehyde at sub-cytotoxic levels.

Induction of skin sensitization is augmented in Nrf2-deficient mice.

Several in vitro DNA microarray studies have shown the importance of nuclear factor (erythroid-derived 2)-like 2 (Nrf2) in skin sensitization. Nevertheless, the exact in vivo role of the Nrf2-Keap1 pathway during the induction of skin sensitization remains unknown. To study the function of Nrf2, a local lymph node assay was performed in wild-type and Nrf2-deficient mice using 2,4-dinitrochlorobenzene.

A quantitative approach to assess the potency of skin sensitizers in the elicitation phase.

The concept that thresholds exist for the induction of allergic contact dermatitis by chemicals with skin sensitizing properties has been used for a quantitative risk assessment approach. In this approach the potency of skin sensitizers as determined in the Local Lymph Node Assay is used to calculate the threshold for induction of sensitization. These are then used to estimate safe exposure levels for consumers.

The effect of particle size on the cytotoxicity, inflammation, developmental toxicity and genotoxicity of silver nanoparticles.

Silver nanoparticles are of interest to be used as antimicrobial agents in wound dressings and coatings in medical devices, but potential adverse effects have been reported in the literature. The most pronounced effect of silver nanoparticles and the role of particle size in determining these effects, also in comparison to silver ions, are largely unknown. Effects of silver nanoparticles of different sizes (20, 80, 113 nm) were compared in in vitro assays for cytotoxicity, inflammation, genotoxicity and developmental toxicity.

Response of MUTZ-3 dendritic cells to the different components of the Haemophilus influenzae type B conjugate vaccine: towards an in vitro assay for vaccine immunogenicity.

Potency testing is mandatory for vaccine registration and batch release. Due to various limitations to in vivo potency testing, there is need for relevant in vitro alternatives. These alternative tests should preferably comprise cells from the target (human) species.

Lipopolysaccharide analogs improve efficacy of acellular pertussis vaccine and reduce type I hypersensitivity in mice.

Pertussis is an infectious disease of the respiratory tract that is caused by the gram-negative bacterium Bordetella pertussis. Although acellular pertussis (aP) vaccines are safe, they are not fully effective and thus require improvement. In contrast to whole-cell pertussis (wP) vaccines, aP vaccines do not contain lipopolysaccharide (LPS).

Lung pathology and immediate hypersensitivity in a mouse model after vaccination with pertussis vaccines and challenge with Bordetella pertussis.

While evaluating vaccine efficacy against clinical Bordetella pertussis isolates in mice, after challenge vaccinated mice showed increased lung pathology with eosinophilia, compared to challenged, non-vaccinated animals. This led us to study bacterial clearance, lung pathology, lung TNF-alpha expression, and parameters of immediate hypersensitivity (IH), being serum IgE levels, eosinophil numbers in the bronchoalveolar lavage fluid, and ex vivo IL-4, IL-5, IL-10, IL-13, and IFN-gamma production by the bronchial lymph node cells. BALB/c mice received a combined Diphtheria (D), Tetanus (T), Poliomyelitis, and whole-cell Pertussis vaccine (WCV), a combined D, T, and three-component acellular Pertussis vaccine (ACV), aluminium hydroxide adjuvant, or PBS, 28 and 14 days before B.

Use of the local lymph node assay in assessment of immune function.

The murine local lymph node assay (LLNA) was originally developed as a predictive test method for the identification of chemicals with sensitizing potential. In this study we demonstrated that an adapted LLNA can also be used as an immune function assay by studying the effects of orally administered immunomodulating compounds on the T-cell-dependent immune response induced by the contact sensitizer 2,4-dinitrochlorobenzene (DNCB). C57Bl/6 mice were treated with the immunotoxic compounds cyclosporin A (CsA), bis(tri-n-butyltin)oxide (TBTO) or benzo[a]pyrene, (B[a]P).

p53 heterozygosity results in an increased 2-acetylaminofluorene-induced urinary bladder but not liver tumor response in DNA repair-deficient Xpa mice.

Both nucleotide excision repair (NER) and the p53 tumor suppressor protein play crucial roles in the prevention of cells becoming cancerous. This is clearly demonstrated by the fact that NER-deficient xeroderma pigmentosum patients and Li-Fraumeni patients who carry a germ-line p53 mutation are highly tumor prone. The NER-deficient Xpa and the p53(+/-) mouse models clearly mimic their human counterparts, because they are both tumor prone as well.

Association of Bordetella pertussis with host immune cells in the mouse lung.

Mouse models are frequently used to study immunity and pathogenesis to Bordetella pertussis infection. To improve the understanding of the mouse infection model, the influx of host cells and B. pertussis localisation in the lungs were evaluated.