Monocyte-Derived Dendritic Cells Can Revert In Vitro Antigen-Specific Cellular Anergy in Active Human Paracoccidioidomycosis

Abstract

We investigated the in vitro effects of two Paracoccidioides brasiliensis antigens on monocyte-derived dendritic cells (moDCs) from patients with paracoccidioidomycosis (PCM). MoDCs from patients with active or treated PCM and non-PCM subjects were generated, stimulated with TNF-α, and P. brasiliensis antigens, 43 kDa glycoprotein (gp43) and cell-free antigen (CFA), and analyzed by flow cytometry and enzyme-linked immunosorbent assays (ELISA). Our data revealed that patients with PCM had a high frequency of HLA-DR+ cells, but the treated group had more CD86+ cells with increased IL-12p40. Patients with active PCM had more CD80+ moDCs, and as a novel finding, large amounts of chemokine (C-C motif) ligand 18 (CCL18) in the supernatants from their in vitro moDC cultures. Both gp43- and CFA-stimulated moDCs from the patients with PCM successfully reverted the in vitro antigen-specific anergy, inducing a proliferative response. However, CFA-stimulated moDCs led to higher lymphoproliferation, with increased IFN-γ and TNF-α in the cells from the patients with active PCM compared with gp43. These original results combined with constant IL-10 and increased IL-12p40 levels suggest that a more complex antigen, such as CFA, may be a better inducer of the protective Th1 immune response than purified gp43 is, and a suitable target for future studies on anti-P. brasiliensis dendritic cell (DC)-based vaccines.

Kinetic Changes in B7 Costimulatory Molecules and IRF4 Expression in Human Dendritic Cells during LPS Exposure

“…The present study aimed to explore the dynamics of B7 costimulatory molecules in an integrative way, encompassing the membrane-bound costimulatory molecules, the soluble B7 costimulatory molecules, and the cytokines found in the microenvironment. Our present model proposed Mo-DCs as archetype APCs due to their feasibility of obtaining a significant yield from peripheral blood mononuclear cells (PBMNCs), as reported in previous studies [ 23 , 24 , 25 ]. On the other hand, the use of LPS as a model antigen has been widely explored due to its capacity to activate innate immune cells and induce the expression of costimulatory molecules and cytokine secretion by DCs [ 26 , 27 , 28 ].…”