sodium-dodecyl-sulfate and 4-phenylenediamine

Topics: Aminopyridines; Anthraquinones; Azo Compounds; Coloring Agents; Cresols; Dimethyl Sulfoxide; Dinitrochlorobenzene; Eugenol; Gene Expression; HaCaT Cells; Hair Dyes; Heme Oxygenase-1; Humans; Hydroquinones; In Vitro Techniques; Keratinocytes; Naphthoquinones; NF-E2-Related Factor 2; Phenylenediamines; Proto-Oncogene Proteins c-fos; Pyrogallol; Resorcinols; RNA, Messenger; Sodium Dodecyl Sulfate

Many attempts have been made to develop in vitro sensitization tests that employ dendritic cells (DCs), DC-like cell lines or keratinocytes. The aim of the present investigation was to establish a co-culture of THP-1 cells and keratinocytes for evaluation of skin sensitization potential of chemicals. Co-cultures were constructed by THP-1 cells cultured in lower compartments and keratinocytes cultured in upper compartments of cell culture inserts. After 24 h exposure to sensitizers (2, 4-dinitrochlorobenzene, p-phenylenediamine, formaldehyde, nickel sulfate, isoeugenol and eugenol) and non-sensitizers (sodium lauryl sulfate, benzalkonium chloride and lactic acid), the expression of CD86 and CD54 on THP-1 cells were evaluated by flow cytometry, and cell viabilities were determined. The sensitizers induced the augmentation of CD86 and CD54 expression, but the non-sensitizers had no significant effect. Compared with mono-cultures of THP-1 cells, the augmentation of CD86 and CD54 could be detected even at a non-toxic concentration of sensitizers in THP-1 cell/keratinocyte co-cultures. Moreover, isoeugenol was distinguished as a sensitizer in co-cultures, but failed to be identified in mono-cultures. These results revealed that the co-cultures of THP-1 cells and keratinocytes were successfully established and suitable for identifying sensitizers using CD86 and CD54 expression as identification markers.

Topics: Animal Testing Alternatives; B7-2 Antigen; Benzalkonium Compounds; Cell Line, Tumor; Cell Survival; Coculture Techniques; Dermatitis, Allergic Contact; Dinitrochlorobenzene; Eugenol; Formaldehyde; Haptens; Humans; Intercellular Adhesion Molecule-1; Keratinocytes; Lactic Acid; Monocytes; Nickel; Phenylenediamines; Sensitivity and Specificity; Skin Tests; Sodium Dodecyl Sulfate

A total of 56 departments of dermatology from Germany, Austria, and Switzerland collaborate to study the clinical epidemiology of contact allergies (CA). Data generated in the course of the diagnostic work-up of CA (e.g., patch test data) have been stored since 1989 in the data center in Göttingen, Germany, including data for more than 200,000 patients (March 2011). These data can be used as a register and as a surveillance system. Analysis of the register may identify and quantify risk factors of sensitization to an allergen, which is exemplified with the case of the allergen para-phenylenediamine. It turned out that-in addition to the risk factor hair dyeing-other important risk factors must be considered. In contrast, data collected every 6 months (from approximately 6,000 patients) allow for time-trend analyses of allergens, thus, identifying allergens of concern, which is of utmost importance for early preventive intervention. Here, the epidemiology of allergies to epoxy resins serves as an example. Continuous monitoring of contact allergens will also be mandatory in the future, as the CA premarketing screening systems will have imperfect predictive values with regard to human CA risk. Unfortunately, the (current) national regulatory framework severely hampers clinical surveillance/epidemiology of contact sensitization and, thus, prevention of contact allergy.

Topics: Adult; Austria; Coloring Agents; Comorbidity; Cross Reactions; Cross-Sectional Studies; Dermatitis, Allergic Contact; Dermatitis, Occupational; Epoxy Resins; Female; Fungicides, Industrial; Germany; Health Surveys; Humans; Male; Phenylenediamines; Population Surveillance; Public Health; Registries; Risk Factors; Sodium Dodecyl Sulfate; Surface-Active Agents; Switzerland; Thiram

The development of non-animal methods for skin sensitization testing is an urgent challenge. Some of the most promising in vitro approaches are based on the analysis of phenotypical and functional modifications induced by sensitizers in dendritic cell models. In this work, we evaluated, for the first time, a fetal skin-derived dendritic cell line (FSDC) as a model to discriminate between sensitizers and irritants, through analysis of their effects on CD40 and CXCR4 protein expression. The chemicals concentrations were chosen based on a slight cytotoxicity effect (up to 15%). Protein levels were evaluated by Western blot and immunocytochemistry, after stimulation with the skin sensitizers 2,4-dinitrofluorobenzene (DNFB), 1,4-phenylenediamine (PPD) and nickel sulphate (NiSO(4)), the non-sensitizer 2,4-dichloronitrobenzene (DCNB), and the irritants sodium dodecyl sulphate (SDS) and benzalkonium chloride (BC). All sensitizers tested increased CD40 and CXCR4 levels. In contrast, irritants decreased both proteins levels, with a more pronounced effect on CXCR4. In agreement with these results, dendritic cells derived from human peripheral blood monocytes-derived dendritic cells (MoDC) showed a similar response pattern to the skin sensitizer and irritant tested, PPD and SDS, respectively. In conclusion, evaluation of CD40 and CXCR4 proteins in chemical-treated FSDC may represent a useful tool in a future in vitro test for sensitizing assessment.

Topics: Allergens; Animal Testing Alternatives; Animals; Benzalkonium Compounds; CD40 Antigens; Cell Line; Dendritic Cells; Dinitrofluorobenzene; Humans; Irritants; Leukocytes, Mononuclear; Mice; Nickel; Nitrobenzenes; Phenylenediamines; Receptors, CXCR4; Skin; Sodium Dodecyl Sulfate

The identification of potential sensitizing chemicals is a key step in the safety assessment process. To this end, predictive tests that require no or few animals and that are reliable, inexpensive and easy to perform are needed. The aim of this study was to evaluate the performance of murine bone marrow-derived dendritic cells (BMDCs) in an in vitro skin sensitization model. BMDCs were exposed to six well-known allergens (dinitrochlorobenzene, DNCB; dinitrofluorobenzene, DNFB; Bandrowski's base, BB; paraphenylenediamine, PPD; nickel sulfate, NiSO(4); cinnamaldehyde, Cinn). Surface expression of MHC class II, CD40, CD54, and CD86 was measured by flow cytometry after 48h exposure to these chemicals. All the allergens tested induced a significant increase in marker expression, with an augmentation in the percentage of mature cells ranging from 2.3- to 10.5-fold change over control. The level of up-regulation was dependent on the concentration and the strength of the allergens. In contrast, the irritants (sodium dodecyl sulfate, SDS and 4-aminobenzoic acid, pABA) and the negative control (zinc sulfate, ZnSO(4)) tested induced either no modification or a down-regulation of membrane marker expression. Taken together, our data suggest that murine BMDCs may represent a new and valuable in vitro model to predict the sensitizing properties of chemicals.

Topics: 4-Aminobenzoic Acid; Acrolein; Allergens; Animals; Antigens, Surface; Bone Marrow Cells; Cell Differentiation; Cells, Cultured; Dendritic Cells; Dinitrochlorobenzene; Dinitrofluorobenzene; Irritants; Lipopolysaccharides; Mice; Mice, Inbred BALB C; Nickel; Phenylenediamines; Sodium Dodecyl Sulfate; Toxicity Tests

The efficacy of a lymph node cell proliferation assay in the guinea pig as a first stage screening method of predicting sensitizing potentials of chemicals was studied by using several haptens. Animals were sensitized by a single 24-hr occlusive patch (24 cp), intradermal injection (id) and a combination of id and 24 cp, at a concentration used for guinea pig conventional contact hypersensitivity assay methods. Control animals were treated with vehicle(s) only. Suspensions of the lymph node cells (LNC) were individually prepared and cultured with [3H]methyl thymidine ([3H]TdR). [3H]TdR incorporation was measured and a stimulation index (SI) was calculated as a ratio of the mean [3H]TdR incorporation in sensitized animals and the mean [3H]TdR incorporation in control animals. LNC sensitized by 24 cp with 2,4-dinitrochlorobenzene proliferated maximally and significantly at day 5, whereas this occurred at day 7 after id sensitization. Significant LNC proliferation and high SI values were obtained successively by a combination of 24 cp and id. Moreover, strongly sensitizing chemicals increased significant LNC proliferation (SI > 2.0); weakly to moderately sensitizing chemicals also induced significant LNC proliferation (SI = 1.3-1.7). On the other hand, a primary irritant, sodium dodecyl sulfate, failed to encourage LNC proliferation (SI approximately 1.0).

Topics: Acrolein; Animals; Benzocaine; Dinitrochlorobenzene; Female; Formaldehyde; Guinea Pigs; Intradermal Tests; Lymph Nodes; Lymphocyte Activation; Neomycin; Nickel; Patch Tests; Perfume; Phenylenediamines; Sodium Dodecyl Sulfate