UC San Diego

The previous studies of the Akt isoforms show that Akt plays a role in cell survivability and growth as well as innate immune system response through macrophage and neutrophil migration and proliferation. However, the role of Akt in Otitis Media pathogenesis is unclear. To mimic otitis media, the middle ears (ME) of Akt1 and Akt2 knockout mice were injected with non-typeable Haemophilus influenzae. When looking at ME mucosal thickness, Akt1-/- mice showed a decrease in thickness at 72 hours while Akt2-/- showed a decrease at 48 hours. In immune system cell count, Akt1-/- mice show an increase in neutrophil count while Akt2-/- mice show a decrease in neutrophil count, both at 48 hours. Finally, the percentage of the ME cavity occupied by inflammatory cells increased at 48 hours in Akt1-/- mice and decrease at 48 hours in Akt2-/- mice. In the immune cell count as well as the percent area covered, Akt1 and Ak2 inhibition leads to a “see-saw” effect where one decreases immune response while the other increases it. This study demonstrates that Akt1 and 2 have a clear role in the ME immune response.