In allergic patients, antibodies like IgE or T-lymphocytes specific for the drugimplicated can be detected and measured. Presence of T-lymphocytes specific for the drugin allergic patients suggested the presentation of the culprit drug to T-lymphocytes byantigen presenting cells like dendritic cells.We were interested in better understanding the implication of T-lymphocytes anddendritic cells in the development of antibiotics allergies such as penicillin G (or Benzyl-Penicillin) or sulfamethoxazole.The results obtained in this work allowed us: i) to demonstrate the presence ofbenzyl-penicillin-specific T cells in the peripheral blood of non-allergic donors, at adetectable frequency; ii) to develop two approaches: one experimental and one usingmodelisation for the identification of epitopes potentially presented to T-lymphocytes andiii) to study the effect of drugs on DC.The perspectives of this research work are to better understand the mechanismsimplicated in drug allergies and to develop predictive tests for “drug allergic potential", inorder to be able to better predict drug allergies during drug development.