Increased LL-37 protein expression in transfected HEK293 cells. Untransfected or hFPRL1-, hMARCO- or hFPRL1/hMARCO-expressing HEK293 cells were incubated with NM or SP for 24 h. Cells were fixed and labelled with anti-LL-37 antibodies and protein expression was examined by immunofluorescence microscopy. Bisbenzimide was used for nuclear counter-staining (blue). The figures show representative results from one of three independent experiments. Scale bar: 20 μm.