Non-human primate orthologues of TMPRSS2 cleave and activate the influenza virus hemagglutinin
(A) Expression of TMPRSS2 in precision-cut lung slices (PCLS) of rhesus macaque origin was analyzed employing immunohistochemistry with an antibody raised against human TMPRSS2 which cross-reacts with the rhesus macaque orthologue. Hematoxylin was used for counterstaining. Omission of the primary antibody served as negative control. (B) Precision cut lung slices (PCLS) prepared from human, rhesus macaque, cynomolgus macaque or common marmoset lung were infected with 3 x 104 ffu of FLUAV A/Hamburg/04/2009 (H1N1, human PCLS) or A/PR/8/34 (H1N1, rhesus, cynomolgus, marmoset PCLS) and treated with the indicated amounts of camostat mesylate. At 48 h post infection, the viral titers in the supernatants were tested using focus formation assay. The results of representative experiments performed with triplicate samples are shown. Error bars indicate standard deviations. Similar results were obtained in three to five independent experiments. ffu, focus forming units.