Chemotactic for neutrophils. Involved in lung-specific neutrophil trafficking during normal and inflammatory conditions. Expression restricted to the lung, produced by bronchoepithelial cells and is released into the airways. Expressed at low levels in fetal lung. By inflammation; in lung. Mice develop normally and are fertile. They display normal leukocyte subpopulations in peripheral blood and bone marrow, but the amount of neutrophils is reduced in the airspace. Susceptibility to pneumonia induced by K.pneumoniae is increased with decreased survival and increased bacterial burden in lung. Belongs to the intercrine alpha (chemokine CxC) family.