MURINE EOTAXIN - AN EOSINOPHIL CHEMOATTRACTANT INDUCIBLE IN ENDOTHELIAL-CELLS AND IN INTERLEUKIN 4-INDUCED TUMOR SUPPRESSION

Guinea pig eotaxin is a recently described member of the Cys-Cys famil y of chemokines and is involved in a guinea pig model of asthma. To de termine whether eotaxin is a distinctive member of this family and to understand its physiologic role, we have cloned the mouse eotaxin gene and determined its structure and aspects of its biologic function. Th e sequence relationship between the mouse and guinea pig genes indicat es that eotaxin is indeed a distinct member of the chemokine family, M oreover, murine eotaxin maps to a region of mouse chromosome 11 that e ncodes other Cys-Cys chemokines. In addition, recombinant murine eotax in protein has direct chemoattractant properties for eosinophils. The eotaxin gene is widely (but not ubiquitously) expressed in normal mice and is strongly induced in cultured endothelial cells in response to interferon gamma. Eotaxin is also induced locally in response to the t ransplantation of interleukin 4-secreting tumor cells, indicating that it likely contributes to the eosinophil recruitment and antitumor eff ect of interleukin 4. Such responses suggest that eotaxin may be invol ved in multiple inflammatory states.