Cell-mediated immunity to respiratory virus infections.

The mucosal surfaces of the lungs pose tremendous problems for an immune system charged with maintaining a sterile pulmonary environment. Despite these problems, the immune system is effective at controlling most pulmonary infections. Over the past few years significant progress has been made in our understanding of how adaptive (humoral and cellular) immunity is able to control infections in the respiratory tract. Recent advances include the identification of effector memory T-cell populations in the lungs and an appreciation for the role of cytokines in regulating memory T-cell pools.