Evaluation of allergenic potential of different raw materials and sunscreen formulations by in vitro and in vivo methods

• Grant number: 13/01219-6
• Support type: Scholarships in Brazil - Doctorate
• Effective date (Start): June 01, 2013
• Effective date (End): January 31, 2017
• Field of knowledge: Health Sciences - Pharmacy
• Principal Investigator: Lorena Rigo Gaspar Cordeiro
• Grantee: Carolina Gomes Benevenuto Moreira
• Home Institution: Faculdade de Ciências Farmacêuticas de Ribeirão Preto (FCFRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil
• Associated scholarship(s): 15/08189-0 - Skin sensitization assessment to UV-filters using reconstituted skin model containing immune cells, BE.EP.DR

Abstract

Contact allergies are considered complex diseases, and it is expected that 15-20 % of the general population suffers from contact allergy. Fragrances, preservatives and hair dyes are considered the most relevant cosmetic allergens. Natural compounds and UV-filters are also considered emerging cosmetic allergens. Concerning the tests used to evaluate the allergenic potential of a chemical, the most commonly used methods still use animal testing, as LLNA - Local Lymph Node Assay, however there are several studies which employ cell culture and reconstructed skin models undergoing international validation processes, including commercial reconstructed skin models which are already validated for safety assessment. In Brazil, the availability of these alternative techniques for cosmetic products routine safety assessments still has some challenges such as the high cost and the need for an efficient importation process of reconstructed skin models. Thus, this study has great importance, once it aims to evaluate the allergenic potential of different raw materials and sunscreen formulations by in vitro and in vivo methods for the development of a safer sunscreen formulation. For this purpose, different UV-filters and preservatives commonly used in sunscreens will be selected. These substances will be tested by peptide depletion assays (GSH, cysteine and lysine), to predict the allergenic potential of chemicals. After that, substances will be analyzed by skin sensitization test by using an in vitro three-dimensional skin model. The amounts of IL-1± and will be analyzed and the MTT assay to assess cell viability and EC-50 will also be performed. After that, sunscreen formulations containing lower allergenic potential components will be prepared and submitted to the evaluation of skin sensitization in the in vitro three-dimensional model and to the clinical evaluation of skin sensitization. (AU)