Functional Ambivalence of Dendritic Cells: Tolerogenicity and Immunogenicity

Abstract

Dendritic cells (DCs) are the most potent professional antigen-presenting cells (APCs) and inducers of T cell-mediated immunity. Although DCs play a central role in promoting adaptive immune responses against growing tumors, they also establish and maintain peripheral tolerance. DC activity depends on the method of induction and/or the presence of immunosuppressive agents. Tolerogenic dendritic cells (tDCs) induce immune tolerance by activating CD4+CD25+Foxp3+ regulatory T (Treg) cells and/or by producing cytokines that inhibit T cell activation. These findings suggest that tDCs may be an effective treatment for autoimmune diseases, inflammatory diseases, and infertility.

The Immunomodulatory Functions of Butyrate

“…In the intestine, DC induce adaptive immune responses in primary T cells bridging the gap between innate and adaptive immunity. 91 , 92 Immature DC help maintain a state of immune tolerance, and mature DC can activate immune responses. Butyrate treatment is reported to have a significant impact on differentiation, maturation, and overall T lymphocyte stimulating effects of human monocyte derived DC.…”

Natural Compound 2,2′,4′-Trihydroxychalcone Suppresses T Helper 17 Cell Differentiation and Disease Progression by Inhibiting Retinoid-Related Orphan Receptor Gamma T

“…During the onset of the disease, inflammatory T cells invading the CNS interact with APCs, which lead to reactivation of T cells and activation of APCs [ 17 ]. Dendritic cells (DCs) and microglia (CD11b + CD45hi + ), which belong to a class of APCs, played a key role in antigen presentation in innate and adaptive immune mechanism [ 18 , 19 ]. The data demonstrated that the proportion of activated microglia did not change obviously ( Supplementary Figure S1A,C ).…”

Mucosal delivery of nanovaccine strategy against COVID-19 and its variants

“…Since the mucosal environment is constantly exposed to diverse commensal and foreign antigens, it is important for the immune system to distinguish between harmless and harmful antigens. In this regard, DCs in the mucosal immune system subtly regulate the balance between immune activation and tolerance 139 . Therefore, for the successful induction of immune response by the mucosal vaccine, it is important to understand and utilize the mechanism of immune regulation mediated by DCs.…”