Opsonization of the C. lunata hyphae also led to the MPO release of the neutrophils indicating that the recognition may be similar to that of A. fumigatus. The fact that we could detect release of MPO when the supernatant of the hyphae was not removed before the infection or even only the supernatant was added to the neutrophil cells suggests that neutrophils could also recognize a soluble factor produced by C. lunata. Here, MPO is linked to infection.