Th and Treg response induced by Aspergillus fumigatus pulsed dendritic cells in vitro

Background Dendritic cells (DCs) can recognize the pathogen-associated molecular patterns (PAMP) of Aspergillus fumigatus (A. fumigatus), activating the immune response. During A. fumigatus infection, a Th and Treg response induced in the fungi-pulsed DCs is not yet well understood. Methods In this study, bone marrow-derived dendritic cells (BMDCs) were separated and proliferated from C57BL/6 mice. A. fumigatus pulsed DCs were generated and cultured with CD4+ T cells derived from the spleen of C57BL/6 mice in vitro. CD4+ T cells differentiation after co-culture were analyzed by flow cytometry, ELISA, and real-time PCR analysis. Results The A. fumigatus pulsed DCs exhibited increased Th1 and Treg frequency, Th1-related cytokines (IFN-γ and IL-12), Treg-related cytokines (TGF-β) and T-bet, and Foxp3 mRNA levels compared with the control group. There was no significant difference between A. fumigatus pulsed DCs group and the control group about Th17 and Th2 frequency. Conclusions The inactivated conidia of A. fumigatus were able to activate BMDCs and made them capable of triggering T cell responses in vitro. A. fumigatus loaded DCs was a weak inducer of Th17 and Th2, but induced a strong Th1 and Treg response.