Cross Talk Between Natural Killer T and Dendritic Cells and Its Impact on T Cell Responses in Infections

Abstract

Both innate and adaptive immunity is vital for host defense against infections. Dendritic cells (DCs) are critical for initiating and modulating adaptive immunity, especially for T-cell responses. Natural killer T (NKT) cells are a small population of innate-like T cells distributed in multiple organs. Many studies have suggested that the cross-talk between these two immune cells is critical for immunobiology and host defense mechanisms. Not only can DCs influence the activation/function of NKT cells, but NKT cells can feedback on DCs also, thus modulating the phenotype and function of DCs and DC subsets. This functional feedback of NKT cells on DCs, especially the preferential promoting effect on CD8α+ and CD103+ DC subsets in lymphoid and non-lymphoid tissues, significantly impacts the systemic and local adaptive CD4 and CD8 T cell responses in infections. This review focuses on the two-way interaction between NKT cells and DCs, emphasizing the importance of NKT cell feedback on DCs in bridging innate and adaptive immune responses for host defense purposes.

Analysis and experimental validation of IL-17 pathway and key genes as central roles associated with inflammation in hepatic ischemia–reperfusion injury

“…A large number of DAMPs can activate the innate immune system by binding to PRRs on the surface of a variety of immune cells, mediating downstream inflammatory pathways to generate a range of cytokines and chemokines. As a conserved T cell subline, NKT cells can be activated and then rapidly produce cytokines in response to antigen presentation by DCs 19 , 20 , while CXCL6-expressing DCs can bind to NKTs expressing the chemokine receptor CXCR6 to promote NKT cell activation/maturation 21 . Activated NKT cells promote CD4 + T cell differentiation and act on Kupffer cells by further generating IL-17, inducing downstream pro-inflammatory mediator expression 22 – 25 , and generating large amounts of ROS, which can further act on HSEC and hepatocytes to promote programmed cellular death or necrosis, expanding the inflammatory cascade 26 (Fig.…”

Harnessing Metformin’s Immunomodulatory Effects on Immune Cells to Combat Breast Cancer

“…Our analysis not only demonstrated an increased percentage of dendritic cells but, importantly, a reduced proportion of immunosuppressive iNOS-producing dendritic cells within the tumor environment of metformin-treated mice ( Figure 5 I,J). These findings imply that metformin’s modulatory effects on the immune system may involve intricate interactions between NKT cells and dendritic cells, thus potentially altering T cell phenotypes to bolster anticancer immunity [ 50 ].…”

Comparative analysis of monocyte-derived dendritic cell phenotype and T cell stimulatory function in patients with acute-on-chronic liver failure with different clinical parameters

“…Dendritic cells (DCs) are an important cell type in the immune system, responsible for antigen presentation and promoting immune responses by activating specific T cells (15). Dendritic cells possess highly differentiated cell surface molecules, including HLA-DR, CD86, and CD54, which play important roles in the process of dendritic cell activation of T cells (21)(22)(23)(24)(25). This study found that patients with ACLF exhibited significantly reduced expression of surface markers HLA-DR, CD86, and CD54 compared to patients with CHB or healthy individuals.…”