Open Access

Stanislaw Schmidt, Marie Luckowitsch, Michael Hogardt, Thomas Lehrnbecher

• Invasive fungal disease (IFD) in hematopoietic stem cell transplantation is associatedwith high morbidity and mortality. As the antifungal host response determines risk and outcomeof IFD, there is growing interest in adoptive immunotherapy using T cells or natural killer (NK)cells. Although the NK-92 cell line has been tested as anticancer therapy in clinical trials, data onthe antifungal activity of NK-92 cells are lacking. Here, we show that the NK-92 cell line exhibitsconsiderable fungal damage on all medically important fungi tested, such as different species ofAspergillus,Candida, mucormycetes, andFusarium. The extent of fungal damage differs acrossvarious species of mucormycetes andFusarium, whereas it is comparable across different species ofAspergillusandCandida. Interferon (IFN)-γlevels in the supernatant were lower when NK-92 cells areco-incubated withAspergillus fumigatus,Candida albicans, orRhizopus arrhizuscompared to the levelswhen NK-92 cells are incubated alone. Different to primary human NK cells, no increase of perforinlevels in the supernatant was observed when the fungi were added to NK-92 cells. Ourin vitrodatademonstrated that the NK-92 cell line could be a feasible tool for antifungal immunotherapy, butdata of animal models are warranted prior to clinical trials.