Life in the balance: killer T-cell self-control fends off lethal influenza?

摘要

The lung is a fragile network of thin-walled alveoli littered with immune cells that are required to carry out the critical, but normal functions, of gas exchange and antigen sampling. In the adult human, this occurs over the expansive surface area of some 70 m~2. The almost constant and direct contact of lung epithelium with the outside environment means that the respiratory tract must maintain a delicate, and tightly regulated balance, to avert almost certain disaster. This is especially true during eradication of a pathogen infection. The fact that lung infection only occasionally goes wrong resulting in a catastrophic outcome suggests that sophisticated mechanisms are in play to keep this process in check.