Cellular therapies supplement: the role of granulocyte macrophage colony-stimulating factor and dendritic cells in regulatory T-cell homeostasis and expansion

摘要

T cells are key effectors of an immune response and are vital to protection from environmental threats. Occasionally, T cells become inappropriately activated, which may lead to a state of chronic inflammation and immunopathology. Thus, several mechanisms are in place to avoid aberrant activation of T cells. One important mechanism that governs appropriate T-cell reactivity lies in thymic education, which involves positive and negative selection of T cells. This process generates T cells that weakly react to self-major histo-compatibility complex (MHQ/peptide complexes (positive selection) but deletes T cells that recognize self-MHC/ peptide complexes too strongly (negative selection). However, a small fraction of T cells may avoid negative selection, which could potentially cause autoimmunity.