The unexpected contribution of conventional type 1 dendritic cells in driving antibody responses

Abstract

Antibodies are hallmarks of most effective vaccines. For successful T-dependent antibody responses, conventional dendritic cells (cDC) have been largely attributed the role of priming T cells. By contrast, follicular dendritic cells and macrophages have been seenas responsible for B cell activation, due to their strategic location within secondary lymphoid tissues and capacity to present native antigen to B cells. This review summarizes the mounting evidence that cDC can also present native antigen to B cells. cDC2 have been the main subset linked to humoral responses, based largely on their favorable location, capacity to prime CD4 + T cells, and ability to present native antigen to B cells. However, studies using strategies to deliver antigen to receptors on cDC1, reveal this subset can also contribute to naïve B cell activation, as well as T cell priming. cDC1 location within lymphoid tissues reveals their juxtaposition to B cell follicles, with ready access to B cells for presentation of native antigen. These findings support the view that both cDC1 and cDC2 are capable of initiating humoral responses provided antigen is captured by relevant surface receptors attuned to this process. Such understanding is fundamental for the development of innovative humoral vaccination approaches.

Transcriptome landscape of high and low responders to an inactivated COVID-19 vaccine after 4 months using single-cell sequencing

“…Our data indicate that samples with high antibody expression 21 days post-second vaccination maintained elevated antibody levels at 4 months. However, it’s important to note that this process predominantly occurs in the germinal centers (GC) of lymph nodes and not in the peripheral blood, hence it’s not depicted in Fig5. Direct B Cell Maturation Induction: Evidence suggests that DCs can directly induce B cell maturation through receptor CD40 [54], including instances where conventional DCs (cDCs) present antigens directly to B cells [55].

Figure 5: Dendritic Cells (DCs) and Their Role in Ribosome Complex Network-Mediated Antibody Production. This figure showcases the complex influence of dendritic cells (DCs) within the ribosome complex network on antibody secretion.

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“…4. Direct B Cell Maturation Induction: Evidence suggests that DCs can directly induce B cell maturation through receptor CD40 [54], including instances where conventional DCs (cDCs) present antigens directly to B cells [55].…”

Organized B cell sites in cartilaginous fishes reveal the evolutionary foundation of germinal centers

“… 35 , 36 Thus far, true FDCs have only been found in mammals and birds; however, it is increasingly apparent that some mammalian cDCs can present intact antigen. 37 Here, we sought to determine if any of the myeloid cells present in the nurse shark spleen might present intact antigen to facilitate B cell clonal selection.…”

Polysaccharides from European Black Elderberry Extract Enhance Dendritic Cell Mediated T Cell Immune Responses

“…In addition, Kinoshita et al reported murine data showing that the oral uptake of elderberry juice induced a dose-dependent stimulatory effect, leading to increased titers of virus-neutralizing antibodies in bronchoalveolar lavage fluids as well as in the serum of the treated mice [ 15 ]. Since DCs are also important for the activation of B cells and thus for the production of antibodies [ 20 ], it is conceivable to speculate that the here reported elderberry extract (EC15), and its fractions, that is, CPS, BOUND and UNBOUND, could also enhance antibody production against, for example, different viruses, in vivo.…”