Redirection of T cells via CAR to fight against Candida albicans infection

Abstract

Candida albicans is the most prevalent cause of invasive candidiasis (IC) in adult and pediatric patients, and this form of candidiasis is related to the translocation of Candida spp from the natural colonization site, such as the gastrointestinal tract and skin, into the bloodstream. The versatility of C. albicans in altering the morphogenesis between yeast and pseudohyphal / hyphal has a strong implication in the evasion of the host's immune response. This occurs mainly due to the differential expression of components of the cell surface and the change in the level of exposure of these elements in the change of morphology. Studies have shown that the involvement of T CD4 + cells of Th1 and Th17 profiles, and the presence of Tc1 and Tc17 profiles, originating from the differentiation of T CD8 + cells, are critical in the resolution of invasive fungal infections (IFIs). However, the microenvironment at the infection site caused by C. albicans has a regulatory character and can compromise an effective immune response. In order to redirect T CD4 + and / or CD8 + cells to the infection site with C. albicans, the current project proposes the use of a chimeric antigenic receptor (CAR) to redirect T cells for the recognition of this pathogen. CAR receptors are composed of four segments: (I) extracellular portion, a target-binding domain; (II) a region called hinge or stalk; (III) a transmembrane region and (IV) a cytoplasmic signaling region. Thus, the C. albicans recognition domain will be present in the CAR to redirect T cells to the infection site, and this domain will be determined by the Phage Display technique to generate different scFv fragments, specific for C. albicans. Then, the specific CAR receptor constructs for C. albicans will be evaluated for specificity and longer-lasting cell activation induction capacity after in vitro assay with C. albicans. The current proposal proposes the use of C. albicans cell wall components in the construction of a scFv immune library, with the aid of the Phage Display technique to express and select the specific antibodies phages for C. albicans. The DNA sequence of the scFv specific for C. albicans will be subcloned into a lentiviral vector containing the other portions of the CAR, composed of CD8-CD137-CD3, to transduce cells of the Jurkat lineage that will serve to evaluate the efficiency of activation via the specific CAR for C albicans after incubation with the pathogen. (AU)