Team JF Nicolas

U851 INSERM - UCBL

Our research focuses on the pathophysiology of inflammatory skin diseases, particularly eczemas and drug allergies. Our goal is to understand the mechanisms underlying the induction of skin immune responses, and the expression of these responses. Our projects involves pre-clinical studies done in mice (INSERM U 851/Gerland) and clinical studies in patients suffering from either eczema or drug allergy (in collaboration with the “Allergology and clinical Immunology Department, Lyon-Sud University Hospital).

an "in vivo" T cell priming model – IFNg local lymph node assay (LLNA) for the sensitizing properties of weak haptens

an "in vitro" T cell priming assay. We show that depletion of naïve PBL in CD25+ T cells allows for the detection of common haptens involved in human ACD.

a new immunobiological assay for the diagnosis of drug allergy using the ELISPOT technology. This assay is able to monitor the number of specific T cells in the blood of drug allergic patients.

4. New approaches for vaccination. Our expertise in skin immunity brought us to participate in R&D projects with Lyonbiopole, the Rhone-Alpes competitivity cluster, in order to develop new approaches for vaccination and diagnostic, using the intradermal route. Our recent study on intradermal vaccination showed that ID vaccination was efficient in immunizing immunocompromized patients who were unresponsive to conventional IM vaccination.

Our research focuses on the pathophysiology of inflammatory skin diseases, particularly eczemas and drug allergies. Our goal is to understand the mechanisms underlying the induction of skin immune responses, and the expression of these responses. Our projects involves pre-clinical studies done in mice (INSERM U 851/Gerland) and clinical studies in patients suffering from either eczema or drug allergy (in collaboration with the “Allergology and clinical Immunology Department, Lyon-Sud University Hospital).

In recent years our main advances include the following: 1. Role of CD8+ T cells in the initiation of the skin inflammation. Our results show that CD8+ T cells are effector cells of skin allergy expressing as eczemas (allergic contact dermatitis and atopic dermatitis) and drug allergies. We reported that CD8+ T cells are in fact mandatory for the initiation of the inflammatory skin response. 2. Characterization of regulatory T cells that control skin inflammation. We showed that CD4+ T reg cells control the expansion and activation of effector T cells in allergic diseases and that the development of the diseases might occur in the case of an imbalance between effector and regulatory T cells. On the basis of different phenotype markers, we demonstrated that the priming of CD8+ T cells is chiefly controlled by a concomitant but independent activation of a discret Treg subset, endowed with highly suppressive activity in vitro. 3. Development of screening methods for compounds endowed with allergenic properties as well as immunobiological diagnostic assays in drug allergy. We developed several models:
-	an "in vivo" T cell priming model – IFNg local lymph node assay (LLNA) for the sensitizing properties of weak haptens
-	an "in vitro" T cell priming assay. We show that depletion of naïve PBL in CD25+ T cells allows for the detection of common haptens involved in human ACD.
-	a new immunobiological assay for the diagnosis of drug allergy using the ELISPOT technology. This assay is able to monitor the number of specific T cells in the blood of drug allergic patients.
4. New approaches for vaccination. Our expertise in skin immunity brought us to participate in R&D projects with Lyonbiopole, the Rhone-Alpes competitivity cluster, in order to develop new approaches for vaccination and diagnostic, using the intradermal route. Our recent study on intradermal vaccination showed that ID vaccination was efficient in immunizing immunocompromized patients who were unresponsive to conventional IM vaccination.