RESUMEN
BACKGROUND: Currently, considerable efforts to standardize methods for accurate assessment of properties and safety aspects of nanomaterials are being made. However, immunomodulation effects upon skin exposure to nanomaterial have not been explored. OBJECTIVES: To investigate the immunotoxicity of single-wall carbon nanotubes, titanium dioxide, and fullerene using the current mechanistic understanding of skin sensitization by applying the concept of adverse outcome pathway (AOP). METHODS: Investigation of the ability of nanomaterials to interact with skin proteins using the micro-direct peptide reactivity assay; the expression of CD86 cell surface marker using the U937 cell activation test (OECD No. 442E/2018); and the effects of nanomaterials on modulating inflammatory response through inflammatory cytokine release by U937 cells. RESULTS: The nanomaterials easily internalized into keratinocytes cells, interacted with skin proteins, and triggered activation of U937 cells by increasing CD86 expression and modulating inflammatory cytokine production. Consequently, these nanomaterials were classified as skin sensitizers in vitro. CONCLUSIONS: Our study suggests the potential immunotoxicity of nanomaterials and highlights the importance of studying the immunotoxicity and skin sensitization potential of nanomaterials to anticipate possible human health risks using standardized mechanistic nonanimal methods with high predictive accuracy. Therefore, it contributes toward the applicability of existing OECD (Organisation for Economic Co-operation and Development) testing guidelines for accurate assessment of nanomaterial skin sensitization potential.
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Rutas de Resultados Adversos , Dermatitis Alérgica por Contacto/etiología , Dermatitis Alérgica por Contacto/inmunología , Fulerenos/efectos adversos , Nanotubos de Carbono/efectos adversos , Titanio/efectos adversos , Antígeno B7-2/metabolismo , Biomarcadores/metabolismo , Citocinas/metabolismo , Dermatitis Alérgica por Contacto/metabolismo , Células HaCaT , Humanos , Inmunomodulación , Queratinocitos/metabolismo , Células U937Asunto(s)
Humanos , Dermatitis Alérgica por Contacto/clasificación , Dermatitis Alérgica por Contacto/diagnóstico , Dermatitis Alérgica por Contacto/fisiopatología , Dermatitis Alérgica por Contacto/inmunología , Dermatitis Alérgica por Contacto/metabolismo , Dermatitis Alérgica por Contacto/prevención & control , Dermatitis Alérgica por Contacto/rehabilitación , Dermatitis Alérgica por Contacto/terapia , Técnicas de Laboratorio Clínico , Técnicas de Laboratorio Clínico/instrumentación , Técnicas de Laboratorio Clínico/normasRESUMEN
BACKGROUND: Expression of murine CCL21 by dermal lymphatic endothelial cells (LEC) has been demonstrated to be one of the most important steps in Langerhans cell emigration from skin. Previously, our group and others have found that this chemokine is up-regulated in different human inflammatory skin diseases mediated by diverse specific immune responses. This study was carried out to investigate the involvement of CCL21 in human skin after challenge with irritant agents responsible for inducing Irritant Contact Dermatitis (ICD). RESULTS: Eleven normal individuals were challenged with different chemical or physical irritants. Two patients with Allergic Contact Dermatitis (ACD) were also challenged with the relevant antigen in order to have a positive control for CCL21 expression. Macroscopic as well as microscopic responses were evaluated. We observed typical ICD responses with mostly mononuclear cells in perivascular areas, but a predominance of polymorphonuclear cells away from the inflamed blood vessels and in the epidermis at 24 hours. Immunohistochemical studies showed up-regulation of CCL21 by lymphatic endothelial cells in all the biopsies taken from ICD and ACD lesions compared to normal skin. Kinetic study at 10, 48, 96 and 168 hours after contact with a classical irritant (sodium lauryl sulphate) showed that the expression of CCL21 was increased in lymphatic vessels at 10 hours, peaked at 48 hours, and then gradually declined. There was a strong correlation between CCL21 expression and the macroscopic response (r = 0.69; p = 0.0008), but not between CCL21 and the number of infiltrating cells in the lesions. CONCLUSIONS: These results provide new evidence for the role of CCL21 in inflammatory processes. Since the up-regulation of this chemokine was observed in ICD and ACD, it is tempting to speculate that this mechanism operates independently of the type of dermal insult, facilitating the emigration of CCR7+ cells.
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Quimiocinas CC/análisis , Irritantes/inmunología , Piel/química , Adulto , Quimiocina CCL21 , Dermatitis Alérgica por Contacto/metabolismo , Dermatitis Irritante/metabolismo , Femenino , Humanos , Inmunohistoquímica , Vasos Linfáticos/química , Vasos Linfáticos/inmunología , Masculino , Persona de Mediana Edad , Piel/inmunología , Regulación hacia ArribaRESUMEN
Chemokines are important players in the development of allergic contact dermatitis (ACD). The participation of secondary lymphoid tissue chemokine (CCL21) is essential in the induction of the disease due to its expression in lymphatic vessels and in secondary lymphoid organs. Since there is no information about its participation during the effector phase of ACD, we studied this chemokine in patients already diagnosed with ACD, who were challenged with the relevant positive and negative (control) antigens. All patients showed a specific antigen-induced immune response characterized by early expression of inflammatory markers in blood endothelial cells followed by dermal accumulation of mononuclear cells with an important increase in infiltration of CXCR3+ but not of CCR7+ cells. In situ hybridization and immunohistochemistry showed low levels of CCL21 in lymphatic vessels at 2 h, whereas they were significantly increased at 10 and 48 h in all positive patch tests. In contrast, very low expression of this chemokine was observed in skin biopsies from the control site at 48 h. In addition, Langerin+ cells, which were present in dermis from positive patch tests at 2 h, were diminished in number at 10 and 48 h, but a significant number of those cells was still present in dermal areas of the control site at 48 h. We demonstrate for the first time that CCL21, a constitutively expressed chemokine, is strongly upregulated in human lymphatic vessels during a Th1/Tc1 allergic inflammatory response. This can provide the signal required for CCR7+ cells to leave the skin through CCL21-positive lymphatic vessels.
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Quimiocinas CC/biosíntesis , Dermatitis Alérgica por Contacto/metabolismo , Adulto , Anciano , Antígenos CD , Antígenos de Superficie/inmunología , Antígenos de Superficie/metabolismo , Biopsia , Quimiocina CCL17 , Quimiocina CCL21 , Quimiocinas CC/genética , Quimiocinas CC/inmunología , Quimiocinas CC/metabolismo , Dermatitis Alérgica por Contacto/genética , Dermatitis Alérgica por Contacto/inmunología , Femenino , Humanos , Inmunohistoquímica , Hibridación in Situ , Lectinas Tipo C/inmunología , Lectinas Tipo C/metabolismo , Tejido Linfoide/inmunología , Masculino , Lectinas de Unión a Manosa/inmunología , Lectinas de Unión a Manosa/metabolismo , Persona de Mediana Edad , Receptores CCR7 , Receptores CXCR3 , Receptores de Quimiocina/inmunología , Receptores de Quimiocina/metabolismo , Regulación hacia ArribaRESUMEN
BACKGROUND: Leucocyte migration within inflammatory skin compartments in allergic contact dermatitis (ACD) is the result of a sophisticated multi-step event where multiple molecules are involved. OBJECTIVE: Since non-antigen-specific mechanisms have been described as an early participant in elicitation of ACD, we investigated the kinetics of the expression of monocyte chemoattractant protein-1 (MCP-1/CCL2) and the type of infiltrating cells. We compared the time course production of MCP-1/CCL2 with connecting segment-1 (CS-1) fibronectin and thymus and activation-regulated chemokine (TARC/ CCL17) expression. METHODS: Biopsies from 10 individuals challenged in their back with the antigen responsible for their contact dermatitis and an irrelevant antigen were taken at different times and histology, immunohistochemistry for CS-1 fibronectin, TARC/CCL17, CD3, CD68, CXCR3, CCR4 and in situ hybridization for MCP-1/CCL2 were performed. RESULTS: At positive antigen stimulated sites expression of MCP-1/CCL2 by basal keratinocytes and isolated cells in dermis started at 10 h. CS-1 fibronectin and TARC/CCL17 expression by blood endothelial cells was found at 2 and 10 h, respectively. This was followed by dermal accumulation of mononuclear cells with a significant increase of CD3+ and CD68+cells. At 48 h, approximately 58% of infiltrating cells were CXCR3+, and 35% CCR4+. CONCLUSIONS: We showed evidence of the fact that CS-1 fibronectin expression precedes the production of MCP-1/CCL2 and TARC/CCL17 in the skin of patients with ACD, suggesting that these molecules participate in the early complex process of migrating mononuclear cells during elicitation of ACD.
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Proteínas Portadoras/biosíntesis , Quimiocina CCL2/biosíntesis , Dermatitis Alérgica por Contacto/metabolismo , Oligopéptidos/biosíntesis , Adulto , Anciano , Biopsia , Quimiocina CCL17 , Quimiocina CCL2/genética , Quimiocinas CC/biosíntesis , Dermatitis Alérgica por Contacto/inmunología , Dermatitis Alérgica por Contacto/patología , Femenino , Expresión Génica , Humanos , Técnicas para Inmunoenzimas , Hibridación in Situ , Masculino , Persona de Mediana Edad , Pruebas del Parche/métodos , ARN Mensajero/genética , Piel/inmunología , Piel/metabolismoRESUMEN
BACKGROUND: Allergic contact dermatitis (ACD) is a common human dermatosis in which not all the mechanisms involved in its pathogenesis have been elucidated. OBJECTIVE: To study the expression of CS-1 fibronectin, TARC and Th1-associated chemokine receptors in biopsies from allergic patch test reactions. MATERIAL AND METHODS: Thirteen patients already diagnosed with ACD were challenged on the back with the antigen responsible of the disease and macroscopic responses and biopsies taken after 48 h. Skin biopsies from negative control challenge sites, AD and ICD were also taken. Samples were fixed, embedded in paraffin wax and processed in order to perform histological and immunohistochemical studies. RESULTS: All subjects with ACD showed a positive clinical response and a perivascular mononuclear cell infiltration at 48 h, which was not seen in the negative controls. The majority of skin-infiltrating cells were CD4+ and CD8+ and up to 54% or 40% of them expressed CXCR3 or CCR5, respectively. We also showed expression of CS-1 fibronectin in inflamed endothelial cells not only in ACD but also in AC and ICD. In contrast TARC was only expressed in ACD and AC. CONCLUSION: We showed for the first time that CS-1 fibronectin is expressed in dermal vessels from allergic patch tests positive reactions, as well as irritant and atopic skin lesions.