Research & Development Division, Jai Research Foundation, Valvada, Gujarat, India.
ALTEX. 2019;36(3):373-387. doi: 10.14573/altex.1811011. Epub 2019 Mar 11.
Chemical substances that induce an allergic response in skin upon contact are called skin allergens or sensitizers, while chemical substances that elicit an allergic response only in presence of light are called photoallergens or photo sensitizers. The Direct Peptide Reactivity Assay (DPRA, OECD N⁰ 442C, 2015) and the Amino Acid Derivative Reactivity Assay (ADRA) are in chemico assays used to discriminate between allergens and non-allergens. The DPRA and the ADRA, respectively, monitor the depletion of model peptides and modified amino acids induced by crosslinking with test chemicals. In the current study we compared these two assays and analyzed their suitability to predict skin sensitization potential of several chemical substances. In order to study the combined effect of a chemical compound and UV light, we modified DPRA (photo-DPRA) as well as ADRA (photo-ADRA) by introduction of a photo-irradiation parameter. Analysis using photo-DPRA and photo-ADRA correctly distinguished known photoallergens from non-photoallergens. Upon irradiation, photoallergens selectively showed higher depletion of model peptides or modified amino acids. Thus, photo-DPRA and/or photo-ADRA can serve as non-animal in vitro methods for the identification and assessment of photoallergens/ photosensitizers.
当化学物质接触皮肤时会引起过敏反应，这些物质被称为皮肤过敏原或敏化剂，而只有在光照下才会引起过敏反应的化学物质则被称为光过敏原或光敏化剂。直接多肽反应性测定法（DPRA，OECD No.442C，2015）和氨基酸衍生物反应性测定法（ADRA）是用于区分过敏原和非过敏原的化学测定法。DPRA 和 ADRA 分别监测模型肽和修饰氨基酸由于与测试化学物质交联而耗尽的情况。在本研究中，我们比较了这两种测定法，并分析了它们预测几种化学物质皮肤致敏潜力的适用性。为了研究化学化合物和紫外线的联合作用，我们通过引入光辐照参数对 DPRA（光 DPRA）和 ADRA（光 ADRA）进行了修改。使用光 DPRA 和光 ADRA 的分析正确地区分了已知的光过敏原和非光过敏原。在照射下，光过敏原选择性地显示出更高的模型肽或修饰氨基酸的耗竭。因此，光 DPRA 和/或光 ADRA 可以作为非动物的体外方法，用于识别和评估光过敏原/光敏化剂。
