Rapamycin enhances IFN-γ and IL-4 production in co-culture of gδ T and dendritic cells from mice with lipopolysaccharide-induced acute lung injury

This study aimed to study the role of rapamycin (RAPA) in modulating the interaction between g delta T cells and dendritic cells (DCs) in a lipopolysaccharide (LPS)-induced acute lung injury mouse model. Mice were injected with LPS to establish the acute lung injury model or LPS + RAPA to assess the role of RAPA in modulating cell interactions. Mice were injected with PBS or RAPA alone as controls. g delta T cells and DCs were isolated from all mice and assessed by flow cytometry and fluorescence microscopy. The isolated g delta T cells and DCs were cultured independently or co-cultured to study their interactions. Enzyme-linked immunosorbent assay was performed to assess the expression of the cytokines, namely, interferon (IFN)-gamma, interleukin (IL)-4, tumor necrosis factor (TNF)-alpha and IL-12 in the individually cultured or co-cultured g delta T cells and DCs, and reverse transcription-polymerase chain reaction (RT-PCR) was employed to investigate the levels of relevant mRNAs. Our study found that co-culture of g delta T cells and DCs from mice treated with LPS + RAPA have reduced expression of IFN-gamma and IL-4 (but not TNF-alpha and IL-12) compared to mice treated with LPS only. These results were confirmed by RT-PCR, where the levels of IFN-gamma and IL-4 mRNA were also reduced. This study may provide useful information in understanding the interaction between g delta T cells and DCs in the LPS-induced lung injury model in mice.