MPO and influenza: Several independent studies revealed beneficial effects of MPO knockdown on disease progression: Deletion of MPO resulted in decreased loss of neurons in the substantia nigra of MPO−/− mice in response to the Parkinsonian agent methyl-phenyl-tetrahydropyridine [34], attenuated LPS-induced acute lung inflammation [35], and preserved expression of TJ-associated claudins in lungs of influenza-infected mice [36].