Mouse Lungkine/CXCL15, also named WECHE, is a member of the ELR motif-containing CXC chemokines. The cDNA of mouse Lungkine encodes a protein of 166 amino acids (aa) with a 25 aa predicted signal peptide and a 141 aa mature protein with an extremely long C terminal tail that protrudes beyond the chemokine fold. Mouse Lungkine shares 35% aa sequence identity with human ENA-78 and 31% identity with human IL-8. The gene for mouse Lungkine has been mapped to chromosome 5. By Northern blot and in situ hybridization, Lungkine transcripts are only specifically detected in the adult and fetal lung, and its expression is up-regulated under inflammatory conditions. Lungkine protein is secreted into bronchoalveolar space and is involved in lung-specific neutrophils trafficking. Studies from Lungkine knock out mice suggests that Lungkine is an important mediator of neutrophil migration from the lung parenchyma into the airspace. Lungkine is also chemotactic for bone marrow progenitor cells and modulates hematopoietic cell differentiation.