Journal of Immunotoxicology最新文献

Flow cytometry using fluorescent antibodies (FC) is the method of choice for the quantitation of proteins expressed at the surface or inside the cell, but, however, does not allow to selectively measure nuclear expression. We therefore sought to develop a method for the extraction of intact cell nuclei, which can be used for their subsequent immunofluorescent analysis by FC. The studied protein was vascular endothelial growth factor-receptor-type 1 (VEGFR-1) which is important in tumor survival and metastasis. Two human cell lines, A431 (epidermoid carcinoma of skin with low invasive and metastatic potential) and BRO (highly aggressive amelanotic melanoma), were used as examples for tumor cells, and normal human fibroblasts PHF served as a control line. The quality of the extracted nuclei was assessed by their intactness and purity from cytoplasm. The high content of the nuclear markers (PCNA = proliferating cell nuclear antigen, lamin A/C) in the extracted nuclei with almost complete absence of the cytoplasmic β-tubulin demonstrated that the protocol can be used to obtain a pure suspension of single intact cell nuclei. The measurement of the nuclear VEGFR-1 content revealed that it was present only in tumor cell nuclei and that in more malignant BRO cells the receptor content was 1.75 times higher than in A431 (p = 0.014). Thus, the developed method of extraction of cell nuclei for subsequent FC analysis is suitable for the quantitative evaluation of protein content in the native nucleus.

Current advances in the study of cutaneous adverse drug reactions can be attributed to the recent understanding that the skin is both a metabolically and immunologically competent organ. The ability of the skin to serve as a protective barrier with limited drug biotransformation ability, yet highly active immune function, has provided insights into its biological capability. While the immune response of the skin to drugs is vastly different from that of the liver due to evolutionary conditioning, it frequently occurs in response to various drug classes and manifests as a spectrum of hypersensitivity reactions. The skin is a common site of adverse and idiosyncratic drug reactions; drug-specific T-cells, as well as involvement of an innate immune response, appear to be key mechanistic drivers in such scenarios. Association of other factors such as human leukocyte antigen (HLA) polymorphisms may play a significant role for particular drugs. This review aims to integrate emerging findings into proposed mechanisms of drug metabolism and immunity in the skin that are likely responsible for rashes and other local allergic responses. These unique biological aspects of the skin, and their translation into implications for drug development and the use of animal models, will be discussed.

Vaccines are inoculated in healthy individuals from children to the elderly, and thus high levels of safety and consistency of vaccine quality in each lot must meet the required specifications by using preclinical and lot release testing. Because vaccines are inoculated into humans, recapitulation of biological reactions in humans should be considered for test methods. We have developed a new method to evaluate the safety of influenza vaccines using biomarker gene expression in mouse and rat models. Some biomarker genes are already known to be expressed in human lymphocytes, macrophages and dendritic cells; therefore, we considered some of these genes might be common biomarkers for human and mice to evaluate influenza vaccine safety. In this study, we used human peripheral blood mononuclear cells (PBMC) as a primary assessment tool to confirm the usefulness of potential marker genes in humans. Analysis of marker gene expression in PBMC revealed biomarker gene expressions were dose-relatedly increased in toxic reference influenza vaccine (RE)-stimulated PBMC. Although some marker genes showed increased expression in hemagglutinin split vaccine-stimulated PBMC, their expression levels were lower than that of RE in PBMC from two different donors. Many marker gene expressions correlated with chemokine production. Marker genes such as IRF7 were associated with other Type 1 interferon (IFN)-associated signals and were highly expressed in the CD304⁺ plasmacytoid dendritic cell (pDC) population. These results suggest PBMC and their marker genes may be useful for vaccine safety evaluation in humans.

Fluoro-edenite (FE) is an asbestiform mineral fiber spotted in the lava rocks excavated from a stone quarry in Biancavilla (Italy). The derived material had been employed locally for building purposes. Previous studies found evidence that exposure to asbestos may induce autoimmunity, with frequency of anti-nuclear autoantibodies (ANA). The aim of this study was to explore the relationship between FE exposure and autoimmune responses in an exposed population. For the study, 60 subjects living in the area of Biancavilla and 60 subjects as control group were randomly invited to participate. A free medical check, including spirometry and a high-resolution computer tomography chest scan, was given to all participants. ANA were determined by indirect immunofluorescence. On medical check, no subject showed any sign and/or symptoms of illness. Prevalence for samples positive to ANA were 70% (n = 42) and 25% (n = 15), respectively, for exposed and non-exposed subjects (p < 0.05). The presence of pleural plaques (PP) was found in 21 (30%) of the exposed subjects and in 2 (3%) of the non-exposed participants. PP subjects were always ANAs positive. In conclusion, as already it was observed with exposure to asbestos fibers, levels of ANA seemed to significantly increase in subjects who had been exposed to FE. Furthermore, all subjects showing PP were also ANA-positive. This first finding in subjects exposed to FE should encourage researchers to further investigate associations between autoimmune unbalance and environmental exposure to asbestiform fibers.